Vectronics VEC-884 User Manual

VEC-884 Owner's Manual

Contents

Fast Start.............................................................................................................1

Before Reading This Manual.......................................................................iv

Chapter 1 Introduction.....................................................................1-1

Introduction to DSP.........................................................................................1-2

Product Overview.............................................................................................1-3

Block Diagram...................................................................................................1-4

Front Panel Layout...........................................................................................1-5

Back Panel Layout............................................................................................1-6

Filter Specifications.........................................................................................1-7

Unit Specifications............................................................................................1-8

General Specifications...........................................................................1-8

Input/Output Specifications................................................................1-8

Chapter 2 Installation.......................................................................2-1

Back Panel Connections...............................................................................2-2

Basic Connections...........................................................................................2-3

Setting Receive Audio Level (Input Level)......................................2-4

Increasing Headphone Audio Level..................................................2-4

Passing Sidetone..............................................................................................2-5

XMIT/RECEIVE Connection.................................................................2-5

CW Sidetone Filter..................................................................................2-6

DSP to TNC Connections..............................................................................2-6

Chapter 3 Operation..........................................................................3-1

Initial Operation..................................................................................................3-2

CW Operation............................................................................................3-3

SSB (and other voice modes) Operation.......................................3-4

Front Panel Description................................................................................3-6

PWR LED.....................................................................................................3-6

Input Level LED..........................................................................................3-6

AGC Button.................................................................................................3-7

Program Button.......................................................................................3-7

Memory Button.........................................................................................3-8

Filters Switch..............................................................................................3-8

Tunable Filters Controls........................................................................3-9

Manual Notch Button.............................................................................3-10

VEC-884 Owner's Manual

Auto Notch Button..................................................................................3-11

Noise Reduction Control.......................................................................3-12

Noise Reduction Button........................................................................3-12

Volume Control.........................................................................................3-12

Speaker Button.........................................................................................3-12

DSP Button.................................................................................................3-13

Power Button.............................................................................................3-13

Chapter 4 Advanced Features......................................................4-1

Memory Filters..................................................................................................4-2

Saving Memory Filters...........................................................................4-2

CW Spotting Tone............................................................................................4-4

Measuring Frequency............................................................................4-4

Talk..........................................................................................................................4-5

Talk Operation............................................................................................4-5

Jumper Settings...............................................................................................4-8

Talk Settings...............................................................................................4-8

Auto Notch Aggressiveness...............................................................4-8

Normal Jumper Settings......................................................................4-8

Normal Jumper Settings Chart................................................4-9

Setting the CW Sidetone Filter..........................................................4-10

Pre-Set Filters............................................................................................4-11

Data Mode Jumper Settings Chart........................................4-12

Chapter 5 Filter Description..........................................................5-1

LR/HR Filter [1]................................................................................................5-2

Band-stop Filter.........................................................................................5-3

BP Filter [2].........................................................................................................5-4

2BP Filter [3]......................................................................................................5-5

CW Filter [4].......................................................................................................5-6

CW Sidetone Filter..................................................................................5-6

SSB Filter [5].......................................................................................................5-7

RTTY Filter [6]....................................................................................................5-7

HF PACKET Filter [7].......................................................................................5-7

AMTOR Filter [8]...............................................................................................5-8

PACTOR Filter [9].............................................................................................5-8

SSTV/FAX/WeFAX Filter [10]..................................................................5-8

Manual Notch Filter.........................................................................................5-9

Automatic Notch Filter..................................................................................5-10

Noise Reduction Filter....................................................................................5-10

Limited Filters.....................................................................................................5-11

Overlapped Filters............................................................................................5-12

VEC-884 Owner's Manual

Appendix A ..............................................................................................A-1

Self-Test................................................................................................................A-2

In Case of Difficulty...........................................................................................A-4

Technical Assistance......................................................................................A-4

MFJ Pre-wired Cables and Open End Cables......................................A-5

Pre-Set and Memory Filters Settings Chart........................................A-6

iii

VEC-884 Owner's Manual Before Reading This Manual

This manual is divided into two parts. The first part, called Fast Start, is meant for people who need to know nothing except how to minimally install the unit and operate it on CW and SSB. The second part, Chapters 1 to 5, is meant for operators who want or need more information. Detailed description of the unit and its operation are described in these chapters.

The first chapter is an introduction to DSP and the VEC-884. The second chapter tells about the back panel and how to install the unit with a radio or TNC. Chapter 3 tells how to operate the unit in CW and SSB and describes the various controls. Advanced Features, Chapter 4, tells how to use the special features o f the VEC-884. The las t c hapter is a des c riptio n of the digital filters used in this unit.

The appendix has two important sections, troubleshooting and technical assistance. There is also a self-test for the unit's digital circuitry and controls. Refer to these sections if you should have any problem with your new VEC-884.

Important:

Please read this section to become familiar with the terms

and mechanics used in this manual.

Whenever the manual text discusses a control, jack, or level adjustment, the name will appear in Bold. Example: Plug a headphone into the Headphones Out jack for ...

The Memo ry/Nor mal Filters button will be referred to simply as the Me mory button throughout this manual.

Definitions for the abbreviations used in this manual are listed below:

LR = Low Reject (Cutoff Frequency) HR = High Reject (Cutoff Frequency) f1 = Center or Notch Frequency #1 f2 = Center or Notch Frequency #2 fc = Center Frequency BW = Bandwidth FIR = Finite Impulse Response IIR = Infinite Impulse Response LMS = Least Mean Square WPM = Words Per Minute

Explanation of graphical symbol: iv

VEC-884 Owner's Manual

The exclamation point within an equilateral triangle is intended to alert you of conditions that may be damaging to the product or resulting in a risk of electric shock to persons.

VEC-884 Fast Start

Fast Start

Beginners' Installation and Operation

To install and use the VEC-884 in the simplest way possible, follow the steps below.

throughout this Fast Start section. SSB also works with AM and FM voice.

1. Install the unit. Follow the installation diagram on the facing page.

2. Set the controls as follows:

3. Apply external power and press and lock the DSP's Power button. The

4. Set the input level.

On some steps we give you a choice of CW or SSB. Choose one

Control Position Meaning AGC button: out AGC off

Program button: N/A N/A Memory/Normal button: out Tunable/Pre-Set Filters switch: Tunable Filters left knob: center middle center freq. Manual Notch button: out manual notch off Tunable Filters right knob: full counter-clockwise widest bandwidth Auto Notch button: out auto notch off Noise Reduction control: full counter-clockwise minimum reduction Noise Reduction button: out noise reduction off Volume control: full counter-clockwise minimum volume Speaker button: in speaker on DSP button: out DSP bypassed Power button: out VEC-884 off

PWR LED on the front panel should light red. If it is green, press the Memory/Normal Filters button.

a. Tune your radio to a b. Set your c. Use a screwdriver to adjust the Receive Audio Adjust (on the back

panel of the DSP) until the Input Level LED (front panel) flashes mostly green and never red (red is too high, off is too low).

radio's

volume control to a normal level.

CW or SSB

station.

CW or SSB filter

Fast Start 1

VEC-884 Fast Start

5. How to operate the CW filter. (If you work SSB skip to step 6)

a. Your radio should still be tuned to a CW station and setup as in step

2 (except Power). Press and lock the DSP button. Adjust the DSP's

volume control. b. Press and hold the red Program button. You will hear a tone. c. Adjust the left Tunable Filters control (center frequency or fc) until

the tone is the same pitch as the CW station. When the tones are

closely matched, release the Program button. d. Slowly adjust the right Tunable Filters control (bandwidth or BW)

clockwise. The CW station's signal should become clearer (less noise

and QRM). e. Practice on other single stations and even with several CW stations

sending at the same time. With practice, you will be able to separate

mixed signals and copy signals that were undetectable without the

filter. Also, experiment with the Noise Reduction, AGC, and Manual

Notch controls.

6. How to operate the SSB filter. (If you work CW skip to step 7)

a. Your radio should still be tuned to a SSB station and setup as in step

2 (except Power). Press and lock the DSP button. Adjust the DSP's

volume control. b. Adjust the right Tunable Filters control (bandwidth or BW) clockwise

to make the SSB signal clearer (less noise and QRM) while not

making the signal less intelligible. c. Adjust the left Tunable Filters control (center frequency or fc) to peak

the signal for maximum intelligibility. d. Re-adjust the right Tunable Filters control (bandwidth or BW)

clockwise to eliminate most of the noise and QRM. At some point

decreasing the bandwidth will make the signal less intelligible. e. Press the DSP button to the "out" position. Find another station that

has CW or some other tone interference audible with a SSB or voice

signal. f. Press the DSP button to the "in" position and filter the voice signal.

Lock the Auto Notch button "in." Any remaining tones should

disappear or be greatly reduced. g. Experiment with different filter adjustments and functions under

various conditions to become familiar with the various controls.

7. Now that you have used the DSP filter you can read other parts of this manual to learn to use the other features of the VEC-884.

Fast Start 2

VEC-884 Owner's Manual

Introduction

Contents of This Chapter

Introduction to DSP Page 1-2

Product Overview Page 1-3

Block Diagram Page 1-4

Front Panel Layout Page 1-5

Back Panel Layout Page 1-6

Filter Specifications Page 1-7

Unit Specifications Page 1-8

General Specifications Page 1-8 Input/Output Specifications Page 1-8

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VEC-884 Owner's Manual Introduction to DSP

The VEC-884

tunable

DSP Filter uses state-of-the-art Digital Signal Processing (DSP) technology. Digital Signal Processing greatly improves signal clarity by reducing or eliminating noise (QRN) and interference (QRM). DSP technology has existed for many years but has always been very complicated and expensive. Recent advances in integrated circuits have greatly inc reased the processing power and reduced the size of DSP units. These same advances also lowered the cost of DSP filtering, making DSP technology affordable for the average amateur or short wave listener.

The heart of any DSP system is the digital signal processor. Almost any microprocessor can perform DSP, such as the one in a personal computer, but only very fast or special-function processors perform DSP in

real time

. A digital signal processor's commands are tailored to the type of instructions used in signal processing. The u se of special DSP commands allows a DSP filter function to be completed in very few clock cycles (usually one). The CPU in a typical personal computer would require a long set of instructions and therefore many clock cycles to perform the same function. Analog Device's 16-bit 12 MHz processor, the ADSP-2105, is used in the VEC-884.

The VEC-884 DSP Filter converts the analog audio signals from your receiver to digital information. This conver sion is achieved by s ampling the audio signal many thousands of times per second with an analog-to-digital converter. The result is a string of digital "numbers" that represent the amplitude and frequency of the analog input signal. The ADSP-2105 chip then pr oces ses the digital information with different digital filter algorithms depending on the settings of the front panel controls. The end result is a digitized signal with undesired signal components either reduced or removed and desired components enhanced. The processed digital signal information is converted back to an audio signal by a digital-to-analog converter and sent to the audio amplifier and line level outputs.

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VEC-884 Owner's Manual

Product Overview

The VEC-884 tunable DSP filter is a highly selective audio filter suitable for most amateur applications. The VEC-884 contains 5 tunable filters, 5 pre-set filters, a tunable manual notch, an automatic notch filter, and an adaptive noise reduction filter. Filter settings can be saved into one of ten memory filter positions.

The 5 tunable filters consist of the following:

LR/HR Low Reject/High Reject BP Band-pass 2BP Double band-pass CW CW mode band-pass SSB SSB mode band-pass

The 5 pre-set data filters are band-pass filters prog rammed with jumpers for the different data modes mark-space frequencies and baud rates:

RTTY HF PACKET AMTOR PACTOR SSTV/FAX/WeFAX

The tunable manual notch filter attenuates 2 tones manually with the front panel controls.

The auto notch filter attenuates up to 4 tones automatically. The automatic notch will attenuate moving or shifting tones. The automatic notch is disabled in the following modes: CW, RTTY, HF PACKET, AMTOR, PACTOR, and SSTV/FAX/WeFAX.

The noise reduction filter uses adaptive and manually adjustable algorithms to provide up to 20 dB noise reduction. The amount of noise reduction is adjustable with a front panel control.

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VEC-884 Owner's Manual Block Diagram

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VEC-884 Owner's Manual

Front Panel Layout

AGC button: Press to enable the automatic gain control;

press again to turn it off.

Program button: Press to program memory filters, to talk, or to

activate CW spotting tone.

Memory button: Selects either normal or memory filters mode. Filters switch: Selects one of ten normal or ten memory

filters.

PWR LED: Indicates normal (red) or memory (green) mode. Input Level LED: Indicates input signal level (red too high, off too

low, green is OK).

Tunable Filters left knob: Adjusts tunable filters and manual notch. Manual Notch button: Press to enable the manual notch; press again

to turn it off.

Tunable Filters right knob: Adjusts tunable filters and manual notch. Auto Notch button: Press to enable the automatic notch; press

again to turn it off.

Noise Reduction knob: Controls the level of noise attenuation. Noise Reduction button: Press to enable the noise reduction; press

again to turn it off.

Volume control: Controls the output volume level to speaker

and headphones jacks.

Speaker button: Press to enable the speaker jack; press again

to turn it off.

DSP button: Press to turn on digital processing of input

signal; press again to bypass processing.

Power button: Press to turn the power on; press again to

turn the power off.

For an in-depth description of the front panel controls, refer to Chapter 3, Operation.

Introduction Error! Main Document Only.-5

VEC-884 Owner's Manual Back Panel Layout

Power: 10-16 Vdc @ .5 amp peak (low "Z " audio load) Headphones Out: 1/4" stereo or mono phone jack Speaker Out: 3.5 mm stereo or mono phone jack Filtered Audio Adjust: screwdriver adjustable potentiometer Filtered Audio Out: RCA phono jack (~1.5 V P-P @ 600 ohms) Receive Audio Adjust: screwdriver adjustable potentiometer Receive Audio In: RCA phono jack To Radio: 5-pin DIN jack

(TNC xmit audio, ground, PTT, receive audio in, XMIT/RECEIVE) To TNC: 5-pin DIN jack (TNC xmit audio, ground, PTT, filtered audio out)

For an in-depth description of the back panel connections, refer to Chapter 2, Installation.

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VEC-884 Owner's Manual

Filter Specifications

Filter Left Control Right Control Attenuation7 Type8

LR/HR1 LR: 200-2200 Hz HR: 1400-3400 Hz 57 dB @ 75 Hz FIR

BP fc: 300-3400 Hz BW: 30-2100 Hz 47 dB @ 60 Hz FIR

2BP2 f1: 300-3400 Hz f2: 300-3400 Hz 47 dB @ 60 Hz F IR

CW3 fc: 300-1000 Hz BW: 30- 700 Hz 47 dB @ 60 Hz FI R

SSB4 fc: 600-1700 Hz BW:1000-2500 Hz 57 dB @ 75 Hz FIR

RTTY Jumper Programmable 47 dB @ 60 Hz FIR

HF PACKET Jumper Programmable 47 dB @ 60 Hz FIR

AMTOR Jumper Programmable 47 dB @ 60 Hz FIR

PACTOR Jumper Programmable 47 dB @ 60 Hz FIR

SSTV/FAX/WeFAX Fixed @1050-1350 Hz an d 1450-2350 Hz 45 dB @ 60 Hz FIR

Manual Notch f1: 150-3400 Hz f2: 150-3400 Hz 40 dB @ 95 Hz IIR

Manual Notch (CW mode) f1: 300-1000 Hz f2: 300-1000 Hz 40 dB @ 105 Hz IIR

Multiple Automatic

Notch5

Random Noise

Reduction6

Note 1: The Note 2: The Note 3: The CW filter has an optional jumper-programmable sidetone filter.

Note 4: The Note 5: The multiple automatic notch has four jumper-programmable levels of aggressiveness and

Note 6: The random noise reduction has a variable level of noise reduction. Note 7: All FIR and II R filter attenuation is indicated in dB @ a distance in Hz outside the pas sband. All LMS

Note 8: All FIR filters are linear phase with a 23 mS time delay and have the upper cutoff frequency limited

FIR - Finite Impulse Response IIR - Infinite Impulse Response LMS - Least Mean Square

LR/HR

all-pass filter when LR is adjusted equal to HR. the two center frequencies.

capable of eliminatin g up t o four changing tones or heterodynes.

filter attenuation is dependent on the characteristics of the noise. to 3900 Hz.

filter becomes a band-stop filter when LR is adjusted higher than HR or becomes an

2BP

filter uses the bandwidth setting last used in BP filter but allows indepe nde nt vari atio n of

SSB

filter has its lower cutoff frequency limited to 175 Hz.

Entire freq. range of the received audio Up to 50 dB LMS

Entire freq. range of selected band-pass filter Up to 20 dB LMS

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VEC-884 Owner's Manual

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VEC-884 Owner's Manual

Unit Specifications General Specifications

Processor

: Analog Devices ADSP-2105. Data width - 16 bits. Clock speed -

12 MHz.

Bypass

: The VEC-884 DSP filter has a direct audio bypass when power switch

is in "off" position.

Input/Output Specifications

: The maximum curr ent demand will be less than 500 mA at maximum

Power

volume but will always be more than 175 mA.

Filtered Audio Out

: This jack provides approximately 1.5 volts P-P into 600 ohm (or higher) impedance loads (160 mW @ 6 ohms). The output voltage of this jack is dependent on Filtered Audio Adjust.

Receive Audio In

: This jack should be driven in a range of 1 to 2.8 volts P-P when Receive Audio Adjust is set to maximum sensitivity. When Receive Audio Adjust is set to minimum sensitivity, the DSP requires a very high input voltage. Input circuit loading is 10 K ohms nominal.

Audio Output

: Audio output power is ≈2.5 watts into a 6 ohm load with the AC12 power supply. Au dio frequency r esponse is fro m 250 to 3100 Hz (-3 dB).

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VEC-884 Owner's Manual

Installation

Contents of This Chapter

Back Panel Connections Page 2-2

Basic Connections Page 2-3

Setting Receive Audio Level (Input Level) Page 2-4 Increasing Headphone Audio Level Page 2-4

Passing Sidetone Page 2-5

XMIT/RECEIVE Connection Page 2-5 CW Sidetone Filter Page 2-6

DSP to TNC Connections Page 2-6

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VEC-884 Owner's Manual Back Panel Connections

: This connector supplies power to the unit. It connects to a 2.1 mm

Power

coaxial plug with the center conductor positive and the shield ground. An optional dc supply, the AC-12, is available from Vectronics. The voltage should be 10-16 Vdc.

the VEC-884 will perform erratically.

Warning:

If the power supply voltage drops below 10 volts

oltages greater than 18 volts or reverse polarity may

permanently damage the VEC-884.

Headphones Out: This jack supplies volume controlled audio for headphones. It

accepts standard male 1/4 inch stereo or mono phone plugs and provides audio to both stereo and mono headphones.

Speaker Out: This jack supplies volume controlled audio for a speaker or

walkman type headphones with 3.5 mm stereo or mono phone plugs. Disengaging the Speaker button disables this jack.

Filtered Audio Adjust: This adjustment varies the level of the audio outputs to

Filtered Audio Out and pin 4 of the To TNC port.

Filtered Audio Out: This jack supplies line level audio for tape recorders or

audio amps. It is a standard RCA phono jack. A quality shielded cable should be used for connections to this jack. The output is dependent on the Filtered Audio Adjust and independent of the DSP's volume control.

Receive Audio Adjust: This adjustment controls the sensitivity of the Receive

Audio In jack and pin 4 of the To Radio port. Proper adjustment is achieved if the Input Level indicator flashes mostly green and never red when the receiver's volume is at normal levels. Refer to page 2-4.

Receive Audio In: This jack is normally connected to the receiver's speaker or

headphones output. It is a standard RCA phono jack. A shielded cable should be used to connect this connector to the station receiver.

To Radio: This port supplies connections for transmit and receive audio. PTT is

connected directly to the To TNC port. A connection is also available for a XMIT/RECEIVE line to automatically bypass the filter during transmit.

To TNC: This port supplies connections to the filtered audio output and the

transmit audio inputs. PTT is connected directly to the To Radio port.

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VEC-884 Owner's Manual

Basic Connections

In the most simple case, the VEC-884 will be installed in the audio path between your receiver and your headphones or speaker.

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VEC-884 Owner's Manual Setting Receive Audio Level (Input Level)

When first connecting the DSP filter and whenever the receiver audio level changes, you should check the Input Level indicator. This LED indicates the input signal level. As a signal is received, the Input Level LED will flash from "off" to either green or red.

If the indicator flashes:

Mostly Green (never red) the input level is adjusted correctly. Any Red the input level is too high. Stays Off (or barely green) the input level is too low.

To set Receive Audio Adjust:

1. Tune your radio to the type of signal you will be operating most.

2. Set your

3. Use a screwdriver to adjust the Receive Audio Adjust ( on the back p anel

of the DSP) until the Input Level LED (on the front panel) flashes mostly green and never red.

Note:

radio's

Some compromise may be required if the receiver does not maintain

volume control to a normal level.

the same audio level on different modes. Set the Receive Audio Adjust on the DSP for the most common mode, and use the receiver's volume knob to properly adjust the level when switching modes.

Increasing Headphone Audio Level

The VEC-884 headphone level is attenuated as it comes from the factory. If a speaker is at a comfortable level and the headphones are too quiet, the level may be raised by using jumpers JMP 9 and JMP 10 (next to the headphones jack).

Warning: Do not short JMP 10 when using a mono phone plug or damage to your unit will result.

To raise the headphone audio level fo r mono headphones, put a 470 ohm or smaller resistor on JMP 9. For stereo headphones, put smaller resistor on JMP 10.

Installation Error! Main Document Only.-4

another

470 ohm or

VEC-884 Owner's Manual

Passing Sidetone

Operators may listen to a station tone with different pitch than the sidetone of their transmitter. In this situation, the DSP filter will attenuate the sidetone and the operator will not be able to monitor his sending. There are two methods of passing sidetone through the DSP filter.

XMIT/RECEIVE Connection

preferred

The (transmit/receive) line on the DSP's To Radio port. All filter functions are bypassed when the XMIT/RECEIVE line is pulled low. The transceiver's sidetone and audio monitoring functions will appear at the DSP output without digital filtering.

The XMIT/RECEIVE line should be connected to an output from your radio that is pulled low when the radio goes into the transmit mode (such as an output for an external RF amplifier). Radio manufacturers call such a line many different names: Relay or RLY; NO or normally open; xmit, transmit or send; or maybe even PTT.

If a linear amplifier is connected to the XMIT/RECEIVE line, a diode (1N4001 or equivalent) should be connected from the linear amplifier's control (relay) jack to the XMIT/RECEIVE line. This diode prevents the amplifier fr om loading the DSP's XMIT/RECEIVE line when the amplifier is turned "off." The anode of the diode should be connected to the amplifier and the catho de (banded end) to the XMIT/RECEIVE line.

method for passing sidetone is the use of the XMIT/RECEIVE

Warning: Never connect the

XMIT/RECEIVE

line to negative

voltages or to positive voltage sources that exceed 35 volts.

The DSP has internal protection circuitry to help prevent other equipment connected to the XMIT/RECEIVE line (such as a linear amplifier) from damaging the unit.

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VEC-884 Owner's Manual CW Sidetone Filter

less preferred

The

method for passing sidetone involves programming a special internal CW sidetone filter. The CW sidetone filter is a totally separate, jumper programmed, constant frequency filter. This option makes the DSP function with two separate parallel filter s. One filter is the standard adjustable CW filter and the other is the fixed frequency CW sidetone filter. This method has the advantage of not requiring a XMIT/RECEIVE connection, but the disadvantage of allowing unwanted signals to feed through if they happen to be within 30 Hz of the sidetone frequency. To enable the CW sidetone filter, internal jumpers must be set to the sidetone frequency of your radio. Refer to page 4-10 for a description of setting the sidetone filter. The center frequency of the sidetone filter ranges from 300 Hz to 1000 Hz in 50 Hz increments. The bandwidth of the sidetone filter is fixed at 50 Hz.

DSP to TNC Connections

When connecting to a TNC, Vectronics suggests the use of the 5-pin ports. TNCs need a PTT connection that is only available on these ports.

The VEC-884 plugs directly into any Vectronics/MFJ/TAPR2 compatible TNC. Use a 5-pin DIN-to-5-pin DIN cable, MFJ-5100, for connection to Vectronics/MFJ/TAPR2 compatible TNCs or the PK-12/96/900. MFJ offers pre-wired radio cables (models MFJ-50xx) for connection to your radio and pre-wired TNC cables (models MFJ-51xx) for connection to other TNCs. Refer to the appendix for more information on these radio-to-TNC cables.

Pin To Radio Function To TNC Function

1 TNC Xmit Audio TNC Xmit Audio 2 Ground Ground 3 PTT PTT 4 Receive Audio In Filtered Audio Out 5 XMIT/RECEIVE No Connection

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VEC-884 Owner's Manual

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VEC-884 Owner's Manual

Operation

Contents of This Chapter

Initial Operation Page 3-2

CW Operation Page 3-3 SSB (and other voice modes) Operation Page 3-4

Front Panel Description Page 3-6

PWR LED Page 3-6 Input Level LED Page 3-6 AGC Button Page 3-7 Program Button Page 3-7 Memory Button Page 3-8 Filters Switch Page 3-8 Tunable Filters Controls Page 3-9 Manual Notch Button Page 3-10 Auto Notch Button Page 3-11 Noise Reduction Control Page 3-12 Noise Reduction Button Page 3-12 Volume Control Page 3-12 Speaker Button Page 3-12 DSP Button Page 3-13 Power Button Page 3-13

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VEC-884 Owner's Manual Initial Operation

Connect the VEC-884 as outlined in Chapter 2. To prepare the unit, set the controls as follows:

Control Position Meaning AGC button: out AGC off

Program button: N/A N/A Memory button: out (normal) Tunable/Pre-Set mode Filters switch: CW CW filter Tunable Filters left knob: center middle center freq. Manual Notch button: out manual notch off Tunable Filters right knob: full counter-clockwise maximum bandwidth Auto Notch button: out auto notch off Noise Reduction control: full counter-clockwise minimum reduction Noise Reduction button: out noise reduction off Volume control: full counter-clockwise minimum volume Speaker button: in speaker on DSP button: out DSP bypassed Power button: out VEC-884 off

Warning: Damage or improper operation may occur if the

polarity, current or voltage of the supply is incorrect. See the installation section on page 2-2. Please don't assume your power supply wiring is correct.

The external power supply should be connected and on. The headphones and/or speaker should be connected to the correct jacks.

Turn the power on by pressing the DSP's Power button. The PWR LED will

red

glow microprocessor is operating. This LED will glow are selected. Press and release the Memory button if this LED is green.

. The red glow indicates the normal filter mode is selected and the

green

if the memory filters

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VEC-884 Owner's Manual

CW Operation

This example will demonstr ate how the CW filter operates and show you how to adjust the audio level from the statio n's receiver for proper DSP operation. If your receiver doesn't operate CW you can skip to the SSB section. That section works for AM, FM, and SSB.

Before attempting to operate your VEC-884, you must familiarize yourself with the DSP controls (be sure yo u have read the preceding sections). Your VEC884 should be set up as outlined in the initial operation section on the preceding page. Tune in a CW station and adjust your receiver for normal comfortable levels of pitch and volume.

Next, push and lock the DSP button "in." Adjust the DSP's Volume control to a comfortable setting. Make sure the left Tunable Filters control is centered, and the right control is fully counter-clockwise.

Note:

Always use the DSP's volume control to adjust the volume when the DSP is "on." Never adjust the receiver's volume knob to control the volume unless the DSP's power is "off."

1. Look at the Input Level LED. If it flashes or lights red, you will have to

decrease the receiver's volume control or adjust the Receive Audio Adjust control on the DSP's back panel towards MIN. If the Input Level LED is flashing or steadily green the audio level is acceptable. The ideal setting is where the LED is as green as possible without ever turning red. (Refer to page 2-4 for a longer explanation.)

2. Press and hold the red Program button. You will hear a tone. Adjust the

left Tunable Filters control (center frequency or fc) until the tone is the same pitch as the CW station. When the tones are closely matched, release the button.

3. Slowly adjust the right Tunable Filters control (bandwidth or BW)

clockwise. This will increase the selectivity. The desired signal should become clearer (less noise and QRM) as the right control is moved clockwise. If turning this control makes the desired signal disappear, the left Tunable Filters control (fc) will have to be re-adjusted.

Please go through steps 2 and 3 several times to get a feel for how the controls act. You will notice tuning becomes more touchy as the BW (bandwidth) control is decreased, but the signal becomes clearer. With a little practice you will become very good at adjusting the filter.

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VEC-884 Owner's Manual

4. Place the DSP button in the "out" position. Tune your receiver until a

frequency is found with several CW signals sending at the same time. When the digital processing is activated by pressing the DSP button "in," you should be able to separate the signals with the Tunable Filters controls. Careful adjustments to the DSP filter's center frequency (with moderate or low bandwidth) may even allow you to copy signals that were undetectable without the filter.

5. Take some time to experiment with the Noise Reduction, AGC, Man ual

Notch, and the Tunable Filters controls in the CW mode. For the best

use of this filter, you should become familiar with the effects of all these controls.

Note:

Most people monitor their sending with a transmitter sidetone oscillator. If you use this common method of monitoring yourself, you have to program a sidetone filter or ground the XMIT/RECEIVE line to monitor yourself. Page 2-5 gives details on this requirement.

SSB (and other voice modes) Operation

The example in this section demons trates the basic SSB filter functions, and allows for further confirmation of the station receiver audio level adjustments. Turn the DSP's Filters switch to SSB mode and place the AGC and NOISE REDUCTION buttons out ("off"). Place the DSP button in the "out" position.

Tune in a SSB, AM or FM station and adjust your radio for normal pitch and volume. Press and lock the DSP button "in." Adjust the Volume control on the DSP to a comfortable volume setting.

Note:

Always use the DSP's volume control to adjust the volume when the DSP is "on" unless specifically told otherwise.

1. Observe the Input Level LED and adjust audio input if the LED is not fully

green without ever flashing red. The ideal adjustment point is when the LED is as green as possible withou t ever flashing red. If the LED is red, reduce the receiver's volume control; if the LED is not lit, increase the receiver's volume control. (Refer to page 2-4.)

2. Adjust the left Tunable Filters control (center frequency or fc) and the

right Tunable Filters control (bandwidth or BW) to peak the SSB signal for maximum intelligibility.

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VEC-884 Owner's Manual

3. You should notice the signal becomes clearer (less noise and QRM) as

the bandwidth (right Tunable Filters control) is moved clockwise and the center frequency (left Tunable Filters control) is re-adjusted. At some point decreasing the bandwidth will make the signal less intelligible. If this happens turn the right Tunable Filters control counter-clockwise.

4. Place the DSP button in the "out" position. Adjust the receiver until you

find a frequency that has CW or any other tone interference audible with a SSB or voice signal.

5. Place the DSP button in the "in" position. Lock the Auto Notch button "in."

The interference should disappear or be greatly reduced.

Note:

The automatic notch will not recognize signals that vary rapidly in frequency or amplitude, becau se the filter mus t ignore ra pid amplitude and frequency changes to avoid nulling or distorting voices. If the automatic notch distorts voice reduce the radio volume slightly or select a less aggressive internal auto notch jumper.

6. Experiment with different filter adjustments and functions under various

conditions to become familiar with the various controls.

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VEC-884 Owner's Manual Front Panel Description

The following section will help you become familiar with the operation of the DSP. The two L EDs are explained first. The buttons, switch, and contr ols are then explained from left to right as they appear on the panel.

PWR LED

This LED lights two different colors, red and green. It helps tell you when the DSP is on and working, and whether the DSP is using the memory or the normal Tunable/Pre-Set filters.

When you turn the DSP power o n, there will be a s light delay and this LED will light. If this LED lights red, the Tunable/Pre-Set filters are being used.

If this LED is green, the memory filters (called Memory) that you can store or program are being used. We explain this in detail as we talk about operating the DSP.

If this LED does not light, or does not change color when the Memory button is changed, the DSP is not operating correctly.

Input Level LED

This LED lights two different colors, red and green. It tells you if the DSP is getting the correct audio level from the receiver.

The volume of the audio from your receiver will change with different signals. Please remember that sometimes there may be a lot of receiver audio, and sometimes there may not. For example, the station you are listening to will probably not be sending all the time, or may be fading in and out.

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VEC-884 Owner's Manual

The use of this LED is very simple. When you are listening to a loud signal, adjust the receiver's volume control so the LED lights the most steady and brightest green possible witho ut ever going red. If the LED doesn't light green on good signals, the receiver volume is too low for the best filter performance. With a properly designed receiver that has a good AGC circuit, you won't have to adjust the receiver volume control very often. You will only have to adjust it when (or if) the Input Level LED indicates improper level by flashing red or failing to light an almost steady green color.

AGC Button

This button controls an automatic gain control (AGC) program. The AGC program automatically adjusts the DSP's internal gain. It tries to make all signals have exactly the same volume. The AGC button setting cannot be stored in memory. It operates independently of all other buttons and controls except the DSP and the Power buttons.

The AGC is activated by pushing and locking this button "in." If the DSP is on and operating, pushing the AGC button "in" will make every s ignal have nearly the same volume level, if the input signal level changes less than 18 dB.

If there is a lot of noise on the signal, you may not want to use the AGC function. It will increase the volume of the noise during long pauses in the signal you are listening to. That can distract you or make it difficult to concentrate on the signal you are listening to.

Program Button

This button is used to make the DSP memorize the filter settings you are currently using. When using the tunable CW filter, this button activates the CW spotting tone. It also starts a "Talk" feature if the DSP button is "out." This button does not stay locked-in like the other buttons, it springs right back out when released.

The use of this button is very special. To use this button to memorize or save a filter, please read the section on page 4-2. To use this button to activate the spotting tone, please read the section on page 4-4. To use this button to start the Talk feature, please read the section on page 4-5.

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VEC-884 Owner's Manual Memory Button

This button allows you to choose two different groups of filters with the Filters switch. This button functions any time the DSP's power is on and the DSP button is "in."

With the Memory button "out," the Filters switch picks one of ten Tunable (front panel adjustable) and Pre-Set (jumper or factory programmed) filters marked LR/HR through SSTV/FAX/WeFAX.

When the Memory button is "in," the Filters switch picks a memory location labeled 1 through 10 on the front panel. The DSP processes the signal using the filter you have stored in that memory location. Page 4-2 gives you more detail on the use of memory.

Filters Switch

This switch picks the main filter used to process the signal. It is used in conjunction with the Memory button we talked about above. It functions whenever the DSP power is on and the DSP button is "in."

Note:

Please remember that when we say Tunable, the main filter's bandwidth and frequencies can be adjusted by the two front panel

Tunable Filters controls. Pre-Set means the front panel Tunable Filters controls cannot be used to adjust the filter. A Pre-Set filter's

mark-space frequencies and bandwidth can only be changed by removing the cover and re-programming internal jumpers (see page 4-

11).

When the Memory button is "out," the Filters switch selects one of the 5 Tunable filters (LR/HR, BP, 2BP, CW, and SSB) or one of the 5 Pre-Set filters (RTTY, HF PACKET, AMTOR, PACTOR, and SSTV/FAX/WeFAX).

When the Memory button is "in," the Filters switch selects any one of ten memory filters you have stored in locations 1 through 10 of the DSP's memory. The Filters switch also selects the memory position (1-10) where you can store the last Tunable/Pre-Set filter you're using.

Chapter 5, Filter Description, gives more detailed information on each filter type available with this switch. Chapter 4, Advanced Features, gives more details on using the memory.

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VEC-884 Owner's Manual

Tunable Filters Controls

The Tunable Filters knobs, left and right, adjust the center frequency (also called the tone or pitch) and the bandwidth (also called the selectivity ) or the lower and upper cutoff frequencies of the 5 Tunable filters selected by the Filters switch. These filters are the LR/HR, BP, 2BP, CW and SSB filters.

These controls also adjust the two manual notch frequencies whenever the

Manual Notch button is "in." Note:

The manual notch function uses the same controls as the main filter. That means any time the manual notch is being used, the adjustable filter cannot be changed.

The following chart tells you what type of adjustment is made by the left and right Tunable Filters controls in every front panel adjustable filter position.

Mode Tunable Filters Left Tunable Filters Right

LR/HR BP 2BP

CW SSB

Manual Notch

* The 2BP's bandwidth (or selectivity) is changed by adjusting the BP's

bandwidth before selecting 2BP.

lowest freq. you will hear highest freq. you will hear center frequency bandwidth * center frequency 1 center frequency 2 center frequency bandwidth center frequency bandwidth notch frequency 1 notch frequency 2

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VEC-884 Owner's Manual Manual Notch Button

When pressed in, this button activates two manually adjustable notch filters. Each filter rem oves a very narrow range of freq uencies or tones. The manual notch operates in every filter mode except when the DSP button is out.

The manual notch is often used to notch out one or two unwanted tones on CW, voice or digital modes. A manually adjusted notch is the only type of notch that operates correctly on CW and digital modes. The manual notch can also remove warbling or buzzing carriers that the automatic notch may ignore. The manual notch also causes less audio distortion in voice modes than an automatic notch.

A manual notch does some things better than the automatic notch. In tone modulated modes the automatic notch wouldn't "know" which tone you wanted to hear and which tone was the interference. It would remove the good signals right along with the bad signals. Since the operator can tell which tones are bad, he/she can use the manual notch to remove them.

The Tunable Filters left and right knobs adjust the frequency of each notch over the entire audio range of the filter . The manual notch bandwidth is very narrow. Tones w ithin 100 Hz o f each no tch fr equenc y will be r educ ed over ten thousand times in volume. If you only need to notch one tone, set the other Tunable Filters control to any end of its range. Doing so will prevent the unused notch from hurting the quality of the signal you want to hear.

One thing is a little tricky when using the manual notch. Since the manual notch uses the Tunable Filters left and right knobs to adjust the notch frequencies, you must select and adjust the correct main filter

before

using the manual notch. The VEC-884 always "remembers" the Tunable Filters left and right knobs settings when the manual notch is engaged and then the Tunable Filters left and right knobs will only adjust the two manual notch frequencies.

Another important thing to remember is when you release the Manual Notch button, the main filter will still remain exactly as it was set. The only thing that will happen is the notch will turn off. But if you adjust or move either Tunable Filters left or right knob, the main filter will quickly jump to the current control settings. If you don't want to loose your original filter settings, don't touch the Tunable Filters left or right knobs after using the manual notch. You can adjust and use the notch as much as you like without affecting the original filter settings whenever the Manual Notch button is "in."

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VEC-884 Owner's Manual

Auto Notch Button

The auto notch does nearly the same job as the manual notch except it finds and removes up to four u nwanted tones very effectively. The main advantage of the auto notch is that it hunts down and removes steady tones without any help from you. The auto notch operates

only in

the LR/HR, BP, 2BP, and SSB

filters regardless of whether they are saved in memory or not. With the Auto Notch button "in," the VEC-884 searches for heterodynes or

steady tones and instantly removes them. It is so good it can remove four drifting tones at the same time, even if the tones are moving in different directions.

The automatic

notch filter has two important limitations. First, it cannot tell the difference between a good tone and a bad tone. Some Filter positions are used for receiving tone signals and the auto notch wouldn't have any idea which tone you really want to copy. Therefore, we can't let you use the auto notch in the following Filters switch positions: CW, RTTY, HF PACKET, AMTOR, PACTOR, and SSTV/FAX/WeFAX. In these modes the auto notch would remove every signal, not just the bad ones.

Second, the automatic notch cannot tell the difference between a voice and a tone that varies rapidly in volume and pitch. If we made the automatic notch remove all the very fast changing tones, it would also remove tones from voices. If we made the automatic notch work only on the slowest changing tones, it would not follow the drifting or fading tones you didn't want to hear.

Because of this limited operating range, we give you two ways to select how quickly and completely the automatic notch works.

One way you can co ntrol the no tch speed is by reduc ing the volume contro l on your receiver slightly. This will lower any distortion on voices while the automatic notch is being used.

The second way to adjust the automatic notch involves removing the DSP's cover and moving two jumpers to different positions. This adjustment allows you to choose four different levels of what we call auto notch aggressiveness.

We ship the DSP in the least aggressive setting (1). If you are unhappy with the notch and would like to step the notch performance up a little bit, you can reset the jumpers. Refer to Jumper Settings on page 4-8. Remember that the automatic notch's distortion of voices will get worse if you choose a more aggressive setting.

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VEC-884 Owner's Manual Noise Reduction Control

This knob controls how much the noise reduction program reduces random noises. Random noises are noises that do not repeat at exactly the same rate. When this control is in the full clockwis e position, random nois es are reduced the maximum amount possible. This control's setting can be used in any active filter mode, including while the Memory button is "in."

Remember to use the least amount of noise reduction necessary. Turning the Noise Reduction control up too far (clockwise) will reduce the audio and cause unnecessary audio distortion and echo. This is an unavoidable side effect of noise reduction at audio fr equencies. The slight echo or hollowness in voices occurs from time delays in the filter and the noise reduction program's effect on random peaks in voices.

Turning off the AGC on the DSP may also reduce how much unwanted noise bothers you.

Noise Reduction Button

This button turns the noise reduction filter on or off. The Noise Reduction button operates in every filter mode, including the memory positions.

Volume Control The Volume control adjusts the audio level at the Headphones Out and the

not

Speaker Out jacks. It does

adjust the audio output level at the Filtered

Audio Out and To TNC output ports. The Filtered Audio Out has a back panel

screwdriver adjustment. This control's position cannot be stored in memory, and it operates all the time. See the block diagram on page Error! Bookmark

not defined.-4.

Speaker Button

This button turns the external speaker on or off. It operates in any position of the Memory button and in every mode as long as the Power button is on.

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VEC-884 Owner's Manual

DSP Button

While "in" this button causes the DSP to digitally process the signal. While "out" this button prevents the DSP from doing any digital processing. It operates in any position of the Memory button.

Non-processed audio is still available at all the audio outputs when this button is in the out position. The only change is the audio output voltage at all the jacks, including the Filtered Audio Out jack, is no longer held constant. The Volume control still functions with the headphones and speaker while the DSP button is "out."

Power Button

This button controls the power to the DSP. It operates in any position of the Memory button.

When the Power button is off (out), this switch connects all the input ports to the speaker and headphones outputs. The F ilter e d Au dio O u t jac k and the To TNC port become "dead." See the block diagram on page 1-4.

Do not use this switch to bypass the DSP. Use the DSP button. You should only use this switch to turn the DSP off after you are completely finished using the DSP.

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VEC-884 Owner's Manual

Advanced Features

Contents of This Chapter

Memory Filters Page 4-2

Saving Memory Filters Page 4-2

CW Spotting Tone Page 4-4

Measuring Frequency Page 4-4

Talk Page 4-5

Talk Operation Page 4-5

Jumper Settings Page 4-8

Talk Settings Page 4-8 Auto Notch Aggressiveness Page 4-8 Normal Jumper Settings Page 4-8

Normal Jumper Settings Chart Page 4-9 Setting the CW Sidetone Filter Page 4-10 Pre-Set Filters Page 4-11

Data Mode Jumper Settings Chart Page 4-12

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VEC-884 Owner's Manual Memory Filters

The VEC-884 allows you to save your favorite filter settings into one of ten "memory filters" in non-volatile memo ry. Whenever you have to r epeatedly set your DSP filter for one station or for similar operating conditions, you may choose to save the settings in memory.

Each position of the Filters switch can select a memory filter for a total of ten filters. These filters are selected when the Memory button is in.

The memory filters store the Filters s witch's Tunable/Pre-Set filter selection and the corresponding filter's center frequency and bandwidth or lower and upper cutoff frequencies, including the CW sidetone filter if set and enabled.

The center frequency and bandwidth or low/high reject frequencies of the filters stored in memory cannot be adjusted. Only the noise reduction and notch filters can be adjusted while using a memory filter (Memory button in).

If you use several different mark-space frequencies, program and save several filters at once. Otherwise you may have to take the cover of the unit off several times. Save a memory filter with each mark-space frequency that you will be using. For programming mark-space frequencies refer to page 4-11.

erase

It is not necessa r y t o

an old memory filter. Old filters are erased when a new filter is saved over them. Use the chart on page A-7 to record your memory filters settings.

Saving Memory Filters

1. With the Memory button out, select and adjust the filter that you want to

save.

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VEC-884 Owner's Manual

2. Press and lock the Memory button in. The PWR LED will now turn green,

indicating the memory filters, and your new filter settings will be saved temporarily until they are saved into a memory position (1-10).

Note:

From steps 2-4 your filter may not appear to work because the filter position (1-10) is still set to the old memory filter.

3. Turn the Filters switch to the position where the new filter is to be saved.

red

4. Press and hold the Program button. The LEDs will light

will beep in one second. Release the Program button. This memory position will now operate with these settings whenever memory mode is selected (Memory button in).

and the DSP

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VEC-884 Owner's Manual CW Spotting Tone

To help you find the center frequency for the CW filter, the VEC-884 is equipped with a CW spotting tone. The spotting tone marks the center frequency of the tunable CW filter and appears when the Program button is pushed in while the DSP button is in. While the spotting tone is present, the bandwidth of the CW filter is opened to maximum allowing you to "zero in" on any CW signal from 300 Hz to 1000 Hz.

As the spotting tone pitch, adjusted with the Tunable Filters left knob, gets close to matching the incoming CW signal's tone, you will hear a beat note. This note will decrease in pitch until a very slow waver or fade is heard in the signals. When this wavering is adjusted to the slowest rate, the center frequency of the CW filter matches the incoming CW signal.

To use the CW spotting tone:

1. Select the CW Filter. The Filters switch must be turned to CW and the

Memory button must be out.

2. Engage the filter by pressing and locking the DSP button in.

3. Press and hold the Program button to activate the spotting tone.

4. Use the Tunable Filters left knob to zero-beat (match) the spotting tone

and the CW signal.

5. Release the Program button.

6. Decrease the bandwidth with the Tunable Filters right knob to eliminate

all other signals.

Measuring Frequency

By using the spotting tone, you can measure the approximate frequency of any audio tone between 300 Hz and 1000 Hz.

1. Disengage the DSP button out to bypass the filter.

2. Select the CW Filter. The Filters switch must be turned to CW and the

Memory button must be out.

3. Engage the filter by pressing and locking the DSP button in.

4. Press and hold the Program button to activate the spotting tone.

5. Use the Tunable Filters left knob to zero-beat (match) the spotting tone

and the signal you wish to measure.

6. Release the Program button.

7. Release the DSP button. Press and release the Program button.

8. Copy the CW. The number following

is the signal's approximate

frequency. (You are using Talk. See the Talk section on page 4-5.)

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VEC-884 Owner's Manual

Talk

In order to know more about the settings of the various filters, Vectronics has provided the Talk function. Talk tells you filter settings by sending them over the audio outputs and by flashing them on the LEDs in Morse code. This feature is extremely useful if you have forgotten the settings for jumper programmed memory filters and you do not wish to remove the cover to reprogram them! When used with the CW spotting tone, this feature also allows you to accurately measure a frequency from 300 Hz to 1000 Hz.

The Talk routine uses the following abbreviations:

CF = C BW = B L = R

= Notch Frequency 2 (Tunable Filters Right Knob)

= Manual Notch

= Automatic Notch

= Noise Reduction

enter Frequency andWidth

Notch Frequency 1 (Tunable Filters Left Knob)

Talk will send the following settings for a selected Normal or Memory filter:

filter mode (LR/HR, BP, 2BP, CW, SSB, RTTY, etc.),

•

lower and upper cutoff frequencies or center frequency and bandwidth,

•

state of the manual notch and its two notch frequencies,

•

state of the auto notch and its aggressiveness level setting (1-4), and

•

state of the noise reduction filter and its front panel level (1-10).

•

The Talk tone frequency and Morse code speed are jumper programmable. Factory default speed is 5 words p er minute (WPM) with a 700 Hz pitch. See Jumper Settings on page 4-8.

Talk Operation

To activate the Talk function:

1. Select a filter using the Filters switch and the Memory button.

2. Set Volume to comfortable listening level.

3. Disengage the DSP button to "out."

4. Press and release the Program button.

5. Listen to the unit send the filter settings (see examples on the next page).

6. At any time, press and lock the DSP button to stop the message.

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VEC-884 Owner's Manual Examples: (These are hypothetical examples.)

Suppose you forget what you stored in memory filter 3. You position the controls as follows:

Control Position Meaning Memory button: in select memory filters

Filters switch: 3 (2BP) memory filter 3 Manual Notch button: out manual notch off Auto Notch button: in auto notch on Noise Reduction control: midrange reduction level 5 Noise Reduction button: in noise reduction on

Auto Notch aggressiveness: jumper-programmed level 3 Then release the DSP button out, press and release the Program button, and

the VEC-884 sends:

BP CF 1025 BW 350 AN 3 NR 5

You now know that in memory position 3 you have a narrow band-pass filter with a bandwidth of 350 Hz and center frequenc y of 1025 Hz. The unit also sent your current settings for notch and noise reduction. Now suppose you try memory filter 6.

Turn the Filters switch to 6 (RTTY). Press the Program button and the VEC-884 sends:

RTTY CF 1360 BW 279 NR 5

In this position, you have saved a jumper-programmed RTTY filter with the center frequency of 1360 Hz and a bandwidth of 279 Hz. These are the settings for European RTTY. Notice that there is nothing sent for auto notch because it is disabled in the RTTY filter.

These are examples of the individual filter settings:

LR/HR

High-pass/low-pass (LR < HR):

•

Band-stop filter (LR > HR):

•

All-pass filter (LR = HR):

•

LRHR 2000-3400 LRHR 0-1400 2200-3900 LRHR 0-3900

Normal filter:

•

Limited filter:*

•

BP CF 1500 BW 2100 BP CF 675 BW 1350

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VEC-884 Owner's Manual

2BP

Normal filter:

•

Overlapped filter:**

•

2BP CF 300 BW 30 CF 3400 BW 30 2BP CF 1000 BW 100

Filter without sidetone:

•

Filter with CW sidetone:

•

Overlapped filter:**

•

SSB

Normal filter:

•

RTTY

2125-2295 Hz 45 baud:

•

HF PACKET

2125-2295 Hz 300 baud:

•

AMTOR

2125-2295 Hz 100 baud:

•

PACTOR

2125-2295 Hz 200 baud:

•

CW CF 700 BW 30 CW CF 400 BW 50 CF 700 BW 30 CW CF 600 BW 100

SSB CF 900 BW 1000

RTTY CF 2210 BW 250

PCKT CF 2210 BW 504

AMTR CF 2210 BW 304

PCTR CF 2210 BW 404

SSTV/FAX/WeFAX

Non-adjustable:

•

SSTV 1050-1350 1450-2350

Manual Notch

Manual Notch On:

•

(when off, MN is not sent)

MN L 150 R 3400

Automatic Notch

On with aggressive level 3:

•

(when off,

Noise Reduction

On with control midrange:

•

(when off,

is not sent)

AN 3

NR 5

* A filter is "limited" by the VEC-884 frequ ency range of 0-3900 Hz or

175 Hz minimum in SSB. The center frequency and bandwidth for these filters are changed to reflect these limits. See the Limited Filters section in Chapter 5.

** An "overlapped" filter occurs when two filters overlap each other

resulting in a single filter capable of passing all the frequencies of the two filters. See the Overlapped Filters section in Chapter 5.

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VEC-884 Owner's Manual Jumper Settings

Several features of the VEC-884 are varied by internal plug -in jumpers. These jumpers are used for:

Talk: set CW tone frequency and Morse code speed Auto Notch: set aggressiveness level CW sidetone: enable and set sidetone filter Data modes: program mark-space frequencies and baud rates

Talk Settings

The Talk routine will "tell" you the DSP's filter settings by sending them in Morse code. Jumpers 1-3 are used for the pitch of the Morse code. Jumpers 4 & 5 are used for the Morse code speed. The DSP is shipped with these jumpers set at 5 WPM and 700 Hz pitch.

Auto Notch Aggressiveness

We ship the DSP in the least aggressive setting (1). If you are unhappy with the notch performance and would like to step it up a little bit, you can reset the jumpers. Remember that the automatic notch's distortion of voices will get worse if you choose a more aggressive setting.

Normal Jumper Settings

Except when programming CW sidetone and data filters, the jumpers are set for the Talk routine and the auto notch aggressiveness settings. After programming a Pre-Set data filter or the CW sidetone filter, the jumpers should be returned to their original positions for Talk and auto notch.

Warning: Remove all power plug from the VEC-884 before

removing the cover. Even though the unit is "off," power is still applied to some circuitry.

To set the tone frequency, code speed, and auto notch level:

1. Disengage (turn "off") the Power button and

remove the power plug

2. Remove the unit's cover (6 screws).

3. Set the jumpers according to the jumper setting table on the next page.

4. Replace the unit's cover (6 screws).

5. Reconnect the power cable and resume normal operation.

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Normal Jumper Settings Chart

JMP 1 JMP 2 JMP 3 Tone

L L L 300 Hz L L H 400 Hz L H L 500 Hz

L H H 600 Hz H L L * H L H 800 Hz H H L 900 Hz H H H 1000 Hz

JMP JMP Code 4

L L * L H 10 wpm H L 20 wpm H H 30 wpm

JMP 6 JMP 7 Auto Notch

L L * L H 2 H L 3 H H 4

This is what the jumpers should look like for the following settings:

1000 Hz Talk pitch, 10 WPM Talk Morse code speed, and Auto Notch level 1.

VEC-884 Owner's Manual

Frequency

700 Hz

5 wpm

Level

Speed

Factory defaults

This is what the jumpers should look like for the default settings:

700 Hz Talk pitch, 5 WPM Talk Morse code speed, and Auto Notch level 1.

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VEC-884 Owner's Manual Setting the CW Sidetone Filter

If you do not have a XMIT/RECEIVE connection and wish to pass CW sidetone through the DSP, you must enable this filter. This is not the preferred method to pass sidetone, see page 2-5. The CW sidetone filter is a jumper programmable internal constant frequenc y filter. It only works in the Tunable CW mode. Any signal within 30 Hz of the sidetone frequency will pass through this filter.

To enable the CW sidetone filter, program it to the sidetone frequency of your radio. The center frequency of the sidetone filter ranges from 300 Hz to 1000 Hz in 50 Hz increments. The bandwidt h of the sidetone filter is fixed at 50 Hz. See the chart below for jumper settings.

The DSP unit is shipped with the CW sidetone filter set to "off." If you wish to disable the filter, program it with all four jumpers in the "H" position.

To set the CW sidetone filter:

1. Disengage the Power button

remove the power plug

and

2. Remove the unit's cover.

3. Set the jumpers for the selected sidetone filter.

4. Turn the Filters switch to CW.

5. Reconnect the power cable.

6. Press and hold the Program

button.

7. Press and lock the Power button to "on."

8. The unit will beep at the new sidetone pitch until the

Program button is released.

9. Disengage the Power button

remove the power plug

and

10. Set the jumpers back to the Talk tone frequency a nd Morse co de speed.

JMP 1 JMP 2 JMP 3 JMP 4 Sidetone

Frequency

L L L L 300 Hz L L L H 350 Hz L L H L 400 Hz L L H H 450 Hz L H L L 500 Hz L H L H 550 Hz L H H L 600 Hz

L H H H 650 Hz H L L L 700 Hz H L L H 750 Hz H L H L 800 Hz H L H H 850 Hz H H L L 900 Hz H H L H 950 Hz H H H L 1000 Hz H H H H *

Factory programmed

OFF

11. Replace the unit's cover.

12. Reconnect the power cable and resume normal operation.

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VEC-884 Owner's Manual

Pre-Set Filters

We have set the RTTY, HF Packet, AMTOR, and PacTOR filters to the most commonly used mark-space frequencies and baud rates. If you wish to change from the factory defaults, you must change the jumpers and program a filter. You may program these filters to a number of mark-space frequencies (shifts) and baud rates. The baud rate setting controls the bandwidth of the filter. Depending on conditions, it is possible to run higher baud rates than are calculated.

The SSTV/FAX/WeFAX filter is fixed. When you program into this position (no change of the jumpers is necessary ), the Pre-Set filters and CW sidetone (not those in memory filters) will reset to the factory defaults. See below.

To set mark-space frequency or reset the filters to the factory defaults*:

1. Press and unlock the Power button to "off" and

remove the power plug

2. Remove the unit's cover (6 screws).

3. Set the jumpers for the selected data filter (see jumper table on next page). Record the Pre-Set filter settings with the chart on page A-7.

4. Turn the Filters switch to RTTY, HF PACKET, AMTOR, PACTOR, or SSTV/FAX/WeFAX *.

5. Reconnect the power cable.

6. Press and hold the Program button.

7. Press and lock the Power button to "on."

8. The unit will beep until the Program button is released.

9. Press and unlock the Power button to "off" and

remove the power plug

10. Set the jumper s back to the Talk tone frequency and Mo rse code speed and the auto notch aggressiveness level. (Refer to page 4-8.)

11. Replace the unit's cover (6 screws).

12. Reconnect the power cable and resume normal operation.

* Factory Filter Defaults

When you program a filter to the SSTV/FAX/WeFAX position, the following filters (not those stored in memory) are reset to the factory defaults as:

Pre-Set Filter Mark-Space Baud Rate

RTTY 2125-2295 Hz 45 HF PACKET 2125-2295 Hz 300 AMTOR 2125-2295 Hz 100 PACTOR 2125-2295 Hz 200

CW Sidetone Set to OFF

Advanced Features Error! Main Document Only.-11

VEC-884 Owner's Manual Data Mode Jumper Settings Chart

JMP 1 JMP 2 JMP 3 JMP 4 Mark-Space

(Shift)

L L L L 1215-1385 Hz (170) L L L H 1275-1445 Hz (170) L L H L 1415-1585 Hz (170) L L H H 1615-1785 Hz (170) L H L L * L H L H 1200-1400 Hz (200) L H H L 1260-1460 Hz (200)

L H H H 1430-1630 Hz (200) H L L L 1600-1800 Hz (200) H L L H 2025-2225 Hz (200) H L H L 2110-2310 Hz (200) H L H H 2125-2325 Hz (200) H H L L 1275-1700 Hz (425) H H L H 2125-2550 Hz (425) H H H L 1275-2125 Hz (850) H H H H 2125-2975 Hz (850)

JMP 5 JMP 6 JMP

L L L * L L H 57 L H L 75 L H H * H L L 110 H L H 150 H H L H H H *

2125-2295 Hz (170)

Baud Rate

100

*200

300

Factory programmed

Data filter center frequency = (mark + space) ÷ 2 Data filter bandwidth = (1.2 x shift) + (baud rate) (ref.: ARRL Handbook)

Advanced Features Error! Main Document Only.-12

VEC-884 Owner's Manual

Filter Description

Contents of This Chapter

LR/HR Filter [1] Page 5-2

Band-stop Filter Page 5-3

BP Filter [2] Page 5-4

2BP Filter [3] Page 5-5

CW Filter [4] Page 5-6

CW Sidetone Filter Page 5-6

SSB Filter [5] Page 5-7

RTTY Filter [6] Page 5-7

HF PACKET Filter [7] Page 5-7

AMTOR Filter [8] Page 5-8

PACTOR Filter [9] Page 5-8

SSTV/FAX/WeFAX Filter [10] Page 5-8

Manual Notch Filter Page 5-9

Automatic Notch Filter Page 5-10

Noise Reduction Filter Page 5-10

Limited Filters Page 5-11

Overlapped Filters Page 5-12

Filter Description 5-1

VEC-884 Owner's Manual

The following section descr ibes the filter s available in the var io us Filters switch positions in detail. All graphs of the following filter s show a line at the noise floor of -55 dB. The response for these digital filters is typically much deeper than -55 dB but circuit noise will generally mask any response below that point.

LR/HR Filter [1]

Use: Custom Voice, FSK, Wide CW Filter. Passes medium to wide frequency width.

This position selects an adjust able low reject/high reject filter. The low reject filter (Low) removes all signals below a user-selected frequency. The low reject filter cutoff frequency c an be varied between 200 Hz and 2200 Hz with the Tunable Filters left knob. The high reject

filter (High) removes all signals above the selected frequency. The high reject limit is adjustable between 1400 Hz and 3400 Hz with the Tunable Filters right knob.

For example: If the low reject filter is adjusted to 900 Hz and the high rejec t

filter is adjusted to 2500 Hz, all fr equenc ies below 900 Hz and above 2500 Hz will be reject ed. In this cas e, the DSP filter will only pass frequencies from 900 Hz to 2500 Hz.

Typical Low Reject/High Reject Filter Response

Frequency (Hz)

0 500 100 0 1500 2000 2500 3000 3500 4000

-10

-20

-30

-40

-50

-60

-70

-80

Filter Description 5-2

VEC-884 Owner's Manual

Band-stop Filter

Use: Rejecting broad or variable frequency signals between 1400-2200 Hz. Removes medium to wide frequency width.

When the low reject filter,

the Tunable Filters left knob, is adjusted to a frequency higher than the high reject filter, the Tunable Filters right knob, the filter removes all frequencies between the two filter settings and passes all frequencies outside the settings of the two filters. This sp ecial filter is called a

band-stop

band-reject

filter. A band-sto p filter makes a "hole" in the middle

of the frequency range and passes everything on either side of the "hole."

For example: If the low reject filter is adjusted to 2200 Hz and the high

reject filter is adjusted to 1600 Hz, all frequencies between 1600 Hz and 2200 Hz will be removed. This creates a hole with a 600 Hz bandwidth.

Typical Band-stop Filter Response

Frequency (Hz)

0 500 1000 1500 2000 2500 3000 3500 4000

-10

-20

-30

-40

-50

-60

-70

Filter Description 5-3

VEC-884 Owner's Manual BP Filter [2]

Use: Custom Voice, FSK, Custom CW Filter. Passes narrow to wide frequency width.

This filter is an adjustable band-pass filter. The bandwidth (BW) is controlled by the Tunable Filters right knob. This adjustment is similar to the selectivity control on a receiver. It can be adjusted from 30 Hz to 2100 Hz. The Tunable Filters left knob varies the center frequenc y (fc) between 300 Hz and 3400 Hz. This adjustment is very much like the pass band tuning or IF shift control on high quality receivers.

For example: If the center frequency (fc) is adjusted to 2200 Hz and the

bandwidth (BW) is adjusted to 600 Hz, all frequencies between 1900 Hz and 2500 Hz will pass. All frequencies not in the 600 Hz bandwidth will be attenuated.

Typical Band-pass Filter Response

Frequency (Hz)

0 500 1000 1500 2000 2500 3000 3500 4000

-10

-20

-30

-40

-50

-60

-70

-80

Filter Description 5-4

VEC-884 Owner's Manual

2BP Filter [3]

Use: Custom Voice, FSK, Dual Pitch CW Filter. Passes 2 independent narrow to wide frequency ranges.

This position allows the use of two frequency-independent variable band-pass filters in parallel. The Tunable Filters left and right knobs control the individual center frequencies (f1 & f2) of the filters.

Each filter has the same bandwidth. The 2BP position uses the bandwidth setting from the BP filter. The bandwidth can be adjusted by switching to the

BP position and adjusting the Tunable Filters right knob.

For Example: To adjust the bandwidth of the 2BP filter, the Tunable Filters

right knob is adjusted to 200 Hz bandwidth while Filters switch is in the BP position. The Filters switch is then turned to 2BP. Now two filters are available, with the Tunable Filters left knob controlling the cent er frequency (f1) of one 200 Hz filter and the Tunable Filters right knob controlling the center frequ ency (f2) of a second 200 Hz filter.

Typical Dual Band-pass Filter Response

Frequency (Hz)

0 500 1000 1500 2000 2500 3000 3500 4000

Filter Description 5-5

-10

-20

-30

-40

-50

-60

-70

-80

VEC-884 Owner's Manual CW Filter [4]

Use: CW Filter, Narrow FSK. Passes "razor sharp" to medium frequency width.

The CW filter is an adjustable band-pass filter that can be varied over the normal frequency range preferred by most CW enthusiasts.

The center frequency (or pitch) is controlled by the Tunable Filters left knob and has a frequency range of 300 Hz to 1000 Hz. This control functions similarly to the pass band tuning or the IF shift control of a receiver with this filter.

The Tunable Filters right knob adjust s the filter bandwid th from 30 Hz to 700 Hz. This knob acts exactly like the selectivity control on a receiver.

Note that as the bandwidth of this filter approaches the on-off rate of the dot and dashes, some ringing may appear. This is an inherent characteristic of any filter when the bandwidth approaches the on-off rate. When this filter is operated using a very narrow bandwidth, some ringing or softening is inevitable. To minimize ringing use the maximum bandwidth possible.

CW Sidetone Filter

Use: To pass CW sidetone Passes any signal very near programmed center frequency.

Note:

This is not the preferred method for passing sidetone. This filter will pass unwanted signals within 30 Hz of the sidetone frequency. See page 2-5, Passing Sidetone.

The CW sidetone filter is a constant frequency filter used to pass sidetone through the DSP. It makes the unit operate as two separate parallel filters: one normal tunable or memory CW filter and the other a constant frequency sidetone filter.

The CW sidetone filter is set at 50 Hz bandwidth. The filter is jumper programmable to center frequencies from 300 Hz to 1000 Hz in 50 Hz increments.

Filter Description 5-6

VEC-884 Owner's Manual

SSB Filter

Use: All Voice modes, FSK, CW Filter. Passes medium to wide frequency width.

The SSB filter is a band-pass filter with adjustable center frequency and bandwidth. The center frequency (fc) is adjusted with the Tunable Filters left knob in a ra nge o f 600 Hz to 1700 Hz. The Tunable Filters right knob adjusts the bandwidth (BW) from 1000 Hz to 2500 Hz. The actua l filter response is limited internally to a minimum of 175 Hz.

While some voice transmiss ions may be understand able with only 1000 Hz of bandwidth if the center frequency is properly adjus ted, the majority of stations will be copied best with the controls nearly centered. The optimum center frequency and bandwidth setting will be determined by the transmitting operator's voice, the transmitter's response, the receiver's response, any noise or QRM, and/or the receiving operator's hearing.

The operator may prefer to monitor himself/herself in the transmit mode. Refer to the section called Passing Sidetone on page 2-5.

[5]

RTTY Filter [6]

Use: RTTY, FSK. Passes high frequency tones with narrow frequency width.

The RTTY filter is factory pre-set for best performance with standard 21252295 Hz mark-space freque ncies (170 Hz shift), 45 baud RTTY s ignals. This filter can also be programmed to one of several different mark-space frequencies and/or baud rates. This procedure is detailed on page 4-11. Under special conditions the o perator may wish to use one of the adjustable band-pass filters in place of the RTTY filter.

HF PACKET Filter [7]

Use: Packet, Wide RTTY, FSK. Passes high frequency tones with medium frequency width.

The HF Packet filter is factory pre-set for best performance with standard 2125-2295 Hz mark-space frequenc ies (170 Hz shift), 300 baud HF Packet signals. This filter can also be programmed to one of several different markspace frequencies and/o r baud rates. This procedur e is detailed on page 4-

11. Under special conditions the operator may wish to use one of the adjustable band-pass filters in place of the HF Packet filter.

Filter Description 5-7

VEC-884 Owner's Manual AMTOR Filter [8]

Use: AMTOR, Narrow PACTOR, Wide RTTY, FSK. Passes high frequency tones with narrow frequency width.

The AMTOR filter is fac tory pr e-set for bes t perfor mance with standar d 21252295 Hz mark-space frequencies (170 Hz shift), 100 baud AMTOR signals. This filter can also be programmed to one of several different mark-space frequencies and/or baud rates. This procedure is detailed on page 4-11. Under special conditions the o perator may wish to use one of the adjustable band-pass filters in place of the AMTOR filter.

PACTOR Filter [9]

Use: PACTOR, Narrow Packet, Wide RTTY. Passes high frequency tones with medium frequency width.

The PACTOR filter is factory pre-set for best performance with standard 2125-2295 Hz mark-space frequencies (170 Hz shift), 200 baud PACTOR signals. This filter can also be programmed to one of several different markspace frequencies and/o r baud rates. This procedur e is detailed on page 4-

11. Under special conditions the operator may wish to use one of the adjustable band-pass filters in place of the PACTOR filter.

SSTV/FAX/WeFAX Filter [10]

Use: Slow Scan, Facsimile. Passes two separ ate frequency ranges, one narrow and one wide frequency width.

This filter is a dual band-pass filter that allows two separate frequency groups to pass through the filter. The first filter is pre-set to pass frequencies between 1050 Hz and 1350 Hz for the synch tone and the Vertical Interva l Signal (VIS) tones. The pictu re c o ntent is p as sed by a second filter at 1450 Hz to 2350 Hz. This filter is non-adjustable and cannot be programmed to different frequencies.

Filter Description 5-8

VEC-884 Owner's Manual

Manual Notch Filter

Use: Removes unwanted tones or heterodynes. Removes up to 2 very narrow frequency ranges and passes all others.

The manual notch filter allo ws the use of two frequency-independent manu ally tunable notch filters. The Tunable Filters left and right knobs control the individual notch frequencies (f1 & f2).

The manual notch has tw o different frequency r anges and widths: o ne for the CW filter and one fo r the other filters. When using the CW filter the notc h is narrower, 45 Hz @ -40 d B, and has a freque ncy range of 300 Hz to 1000 Hz (same as the CW filter). In all other modes the notch is wider, 85 Hz @ -40 dB, and has a frequency range of 150 Hz to 3400 Hz.

For Example: There is RTTY in your SSB audio. After engaging the Manual

Notch button, use the Tunable Filters

left and right knobs

notch the two RTTY tones at 2125 and 2295 Hz.

Typical Manual Notch Filter Response

Frequency (Hz)

0 500 1000 1500 2000 2500 3000 3500 4000

-20

-40

-60

-80

-100

-120

Filter Description 5-9

VEC-884 Owner's Manual Automatic Notch Filter

Use: Removes multiple tones or heterodynes quickly. Removes up to 4 changing tones in the presence of speech signals.

The multiple automatic notch filter searches for and eliminates up to four changing or shifting tones in milli-seconds, with attenuation as great as 50 dB. All the notches are extremely narrow, res ulting in a minimal effect on the voice signals. The automatic

notch filter is disabled in the following filter modes: CW, RTTY, HF PACKET, AMTOR, PACTOR, and SSTV/FAX/WeFAX (including those stored in memory).

There is an adjustment to change the "speed" of the automatic notch filter. We call this adjustment the automatic notch aggressiveness. By changing a jumper setting, this aggressiveness can be changed in a range of four levels. See the jumper setting section on page 4-8.

Noise Reduction Filter

Use: Removes random noises such as white noise, background hiss, etc. Removes random noises and passes coherent signals like voices.

The random noise reductio n filter effec tively r emoves no ises in the presenc e of voice with minimal degradation of the voice itself. The noise reduction filter works by auto matically for ming consta ntly-varying band-p ass filters around the coherent components, such as speech, of the audio signal. In effect, this provides noise reduction by reducing the individual filters' bandwidths to the minimum required to pass the speech signals intelligently. This filter greatly reduces operator fatigue during long-term monitoring and makes listening much more pleasant.

There is a noise reduction control to adjust the reduction characteristics of the noise reduction filter to prevent s ignal distortion. When this control is in the full clockwise position, random noises can be attenuated up to 20 dB (depending on the types of noises).

Filter Description 5-10

VEC-884 Owner's Manual

Limited Filters

Filter response is limited to the frequency range of 0-3900 Hz or 175 Hz minimum in SSB mode. When a filter's center frequency setting is low or high enough that the bandwidth w ould exceed these frequency ranges, the filter is "limited." The filter actually changes its center frequency and bandwidth settings so that it does not exceed these frequency ranges.

Limited filters are pro bably not even noticed by the cas ual operator. However when using the Talk featur e, an operator may notice a difference in the front panel controls and the Tunable Filters left and right knob settings. Limited filters can only occu r in the following filter modes: LR/HR, BP, 2BP, CW, and SSB.

For example: The Filters switch is set to BP. The Tunable Filters left knob is

set at a 300 Hz center frequency and the Tunable Filters right knob is set to a bandwidth of 2000 Hz. Obviously the lower cutoff frequency cannot be -700 Hz. Since the DSP's frequency range stops at zero, the filter must stop at zero. The filter's upper cutoff frequency is 1000 Hz above the center frequency, 1300 Hz. In this case, the DSP limits the BP filter to 0-1300 Hz (a low-pass filter). Therefore when the Talk feature is used, the DSP will send the following:

BP CF 650 BW 1300

Filter Description 5-11

VEC-884 Owner's Manual Overlapped Filters

When the passbands of two filters touc h each other, the filters are said to be "overlapped." The result is a single band-pass filter capable of passing all the frequencies of the two individual filters. The filter actually changes its center frequency and bandwidth settings so that the two individual filters are effectively implemented as a single filter.

The new center frequency, fc, is at the center of the lowest cutoff frequency and the highest cutoff frequency of the two individual filters:

The new bandwidth, BW, is equal to the sum of the two individual filters' bandwidths, BW1 and BW2, minus the overlapped region:

Overlapped filters are not notic eable by the oper ato r. Ho wever when us ing the Talk feature, an operator may notice a difference in the front panel controls and the Tunable Filters left and right knob settings. Overlapped filters can only occur in the following filter modes: 2BP and CW with sidetone filter enabled.

fc = (lowest cutoff freq. + highest cutoff freq.) ÷ 2

BW = BW1 + BW2 - (overlapped region)

For example: The Filters switch is set to 2BP. The Tunable Filters left and

right knobs are set at center frequencies of 2000 Hz and 2400 Hz, respectively. The bandw idth of each filter is 600 Hz. In this case, the upper cutoff frequency of the first filter is 2300 Hz and the lower cutoff frequency of the second filter is

2100. Obviously the two filters overlap each o ther by 200 Hz; therefore, the DSP implements these two filters as a single band-pass filter. When the Talk feature is used, the DSP will send the following:

2BP CF 2200 BW 1000

Filter Description 5-12

VEC-884 Owner's Manual

Appendix

Contents of This Appendix

Self-Test Page A-2

In Case of Difficulty Page A-4

Technical Assistance Page A-4

MFJ Pre-wired Cables and Open End Cables Page A-5

Pre-Set and Memory Filters Settings Chart Page A-6

Appendix A-1

VEC-884 Owner's Manual Self-Test

This self-test is used to test all the digital circuitry, switches, and controls of the VEC-884.

To perform the self-test:

1. Turn the Filters switch to BP.

2. Push all buttons so they are in the "out" position.

3. Turn all knobs to full clockwise, except Volume. Set Volume to a

4. Disengage the Power button and

5. Remove the DSP's cover (6 screws).

6. Remove all jumpers from JMP1 to JMP7. Record their positions to re-

7. Reconnect power.

8. Press and hold the Program button.

9. Press and lock the Power button to "on."

10. Release the Program button. The unit sends

11. Test each button (except the Speaker and Power buttons) by pressing:

12. Test the Filters switch by turning it to each position: LR/HR, BP, 2BP,

13. Test the left Tunable Filters knob by turning it to full counter-clockwise

14. Test the right Tunable Filters and Noise Reduction knobs in the same

15. Test the jumper connections by placing plug-in jumpers on the "L"

Important:

comfortable listening level.

remove the power plug

configure the unit after the self-test.

SELF TEST

10 WPM each operation. If the LEDs blink red the unit fails the test and a Morse code message is sent to indicate the nature of the failure.

AGC, Program, Memory, Manual Notch, Auto Notch, Nois e Reduction, and DSP buttons. Skip the Speaker and Power buttons. The LEDs should blink green once after each button push.

CW, SSB, RTTY, HF PACKET, AMTOR, PACTOR, and SSTV/FAX/ WeFAX. The LEDs should blink green once after each turn of the switch.

then to full clockwise. The LEDs should blink green once at each end. way. The LEDs should blink green once at each end. positions of JMP1 to JMP7 (JMP8 is not used). The LEDs should blink

green once for each jumper.

For the entire test, the LEDs should blink green once after

Performing the next step will reset the CW sidetone and the

in Morse code at

Pre-Set data filters to factory defaults as described on page 4-

11. If you do not want these filters to reset to factory defaults, stop this self-test now by releasing the Power button.

Appendix A-2

VEC-884 Owner's Manual

16. Test the XMIT/RECEIVE line by short ing pin 5 of the To Radio connector

to ground for approximately one second or until the LEDs blink. If it is shorted for less than one second, the DSP might signal a false failure. The LEDs should blink green once when the XMIT/RECEIVE line is grounded for one second.

17. The filter EEPROM memory, IC U8, is then tested without assistance.

Note that this step will reset the CW sidetone and the Pre-Set data filters to factory defaults.

18. If you've pressed the buttons, turned the switch and the knobs, placed the

jumpers, and grounded the XMIT/RECEIVE sense line in the correct order and the unit is working properly, the unit repeatedly sends (with blinking green LEDs) in Morse code. A repetitive message such as

B4 FAIL

correct order or the unit failed the test. The prefix and the number indicate the nature of the failure (see table below).

19. Disengage the Power button and

20. Replace all jumpers from JMP1 to JMP7 to their original positions.

21. Replace the DSP's cover (6 screws).

22. Reconnect power and resume with normal operation.

= AGC button

= PROGRAM button

= MEMORY button

= MANUAL NOTCH button

= AUTO NOTCH button

= NOISE REDUCTION button

= SPEAKER button *

= DSP button

= POWER button *

= JMP1 jumper

= JMP2 jumper

= JMP3 jumper

= JMP4 jumper

= JMP5 jumper

= JMP6 jumper

= JMP7 jumper

(with blinking red LEDs) indicates that you didn't follow the

remove the power plug

Prefix-Number and Its Designation

= LR/HR switch position

= BP switch position

= 2BP switch position

= CW switch position

= SSB switch position

= RTTY switch position

= HF PACKET switch position

= AMTOR switch position

= PACTOR switch position

= SSTV/FAX/WeFAX switch position

= TUNABLE FILTERS left knob

= TUNABLE FILTERS right knob

= NOISE REDUCTION knob

= VOLUME knob *

= XMIT/RECEIVE sense

= EEPROM -- IC U8

PASS

Appendix A-3

VEC-884 Owner's Manual

* These controls are included here for completeness even though they are

not directly tested by this self-test.

Appendix A-4

VEC-884 Owner's Manual In Case of Difficulty If you experience low volume, hum only when the DSP volume control is

high, or distortion:

Double check the wiring used to connect the DSP to the receiver's speaker and headphones jacks. The wiring can be tested by turning the DSP "off". When the DSP power switch is in the "off" position, the audio input jack is connected directly to the DSP's sp eaker and headphones jacks. If the DSP is properly connected and the wiring is good, the volume level and audio quality should be exactly the same as when the speaker or headphones is plugged directly into the receiver's speaker or headphones jacks.

If the DSP fails to process properly when using the Automatic Notch or Noise Reduction, or if the DSP audio is distorted intermittently:

The receiver's volume or the DSP's level control may need to be adjusted. Check the Input Level LED.

If you hear hum at high or low volume:

The power supply you are using may not be filtered properly.

If the DSP won't start or shuts off intermittently:

The power supply may not be within the required 10-16 volt range. If the power supply drops below 10 volts from poor regulation or a bad connection, the DSP may operate erratically An indication of poor power is the power LED flashing from red and green.

Technical Assistance

If you have any problem with this unit first check the appropriate section of this manual. If the manual does not reference your problem or your problem is not solved by reading the manual you may call Vectronics toll-free at 601-323-

5800. You will be best helped if you have your unit, manual and all information on your station handy so you can answer any questions the technicians may ask.

You can also send questions by mail to Vectronics, 1007 HWY 25 South, Starkville, MS 39759 or by FAX to 601-323-6551. Send a complete description of your problem, an explanation of exactly how you are using your unit and a complete description of your station.

Appendix A-5

VEC-884 Owner's Manual MFJ Pre-wired Cables and Open End Cables

The following MFJ radio-to-TNC cables are pre-wired for most 8-pin rigs and HTs. The open end cables allow you to make your own cables. For your nearest dealer or to order call toll-free 800-647-1800.

Pre-wired Radio-to-DSP Cables

Radio

MFJ Part #

Icom1/Yaesu/Alinco/Radio Shack HTs MFJ-5024 $14.95 Kenwood2 HTs MFJ-5026 $14.95 Yaesu 8-pin MFJ-5080 $14.95 Yaesu 8-pin modular MFJ-5080M $14.95 Icom3 8-pin MFJ-5084 $14.95 Icom4 8-pin modular MFJ-5084M $14.95 Kenwood/Alinco 8-pin MFJ-5086 $14.95 Kenwood 8-pin modular MFJ-5086M $14.95 Radio Shack 8-pin modular MFJ-5088M $14.95 MFJ-8621 Data Radio MFJ-5100 $14.95

Note 1: Doe s not include IC-W2A. Note 3: Does not include 25A, 255A. Note 2: Does not include 2500. Note 4: Does not include IC-100H, I C-2700H.

Price

Pre-wired DSP-to-TNC Cables

TNC

All MFJ TNCs/PK-900/PK-96/PK-12/PacCom/

MFJ Part #

MFJ-5100 $14.95 other TNC-2 compatibles PK-232 MFJ-5100X $14.95 KAM HF5/KAM VHF5/KPC35/KPC96125 MFJ-5100YH6 $14.95 MFJ-5100YV7 $14.95 PK-88 MFJ-5100Z $14.95

Note 5: YH for KAM HF port. YV for KAM VHF port. Other Kantronics use YV models. Note 6: YH models for KPC9612 9600 baud port. Note 7: YV for KPC9612 1200 baud port.

Price

Open End Cables With Radio Connectors

Open End Cable ...

... with 8-pin mic connector MFJ-5082 $9.95 ... with 5-pin DIN connector (general purpose) MFJ-5205 $4.95 ... with split connectors for Alinco & other hand-helds MFJ-5222 $9.95 ... for Icom/Yaesu/Alinco/Radio Shack hand-helds MFJ-5224 $9.95 ... for Kenwood hand-helds MFJ-5226 $9.95 ... with 8-pin modular mic plug for Yaesu, Ke nwood,

Icom, and Radio Shack

Prices as of June 30, 1995. Prices subject to change without notice.

MFJ Part #

Price

MFJ-5268 $9.95

Appendix A-6

VEC-884 Owner's Manual

Pre-Set and Memory Filters Settings Chart

Copy this chart and use it to record your Pre-Set and memory filters settings. Use the Talk function to get the frequency values for CF, BW, and/or LR-HR.

Pre-Set RTTY Mode

Mark-Space _____________________ Baud Rate _____________________

Pre-Set AMTOR Mode

Mark-Space _____________________ Baud Rate _____________________

Pre-Set HF PACKET Mode

Mark-Space _____________________ Baud Rate _____________________

Pre-Set PACTOR Mode

Mark-Space _____________________ Baud Rate _____________________

Memory 1

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 3

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 5

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 7

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 9

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Mode: ___________

Mode: ____________

Mode: ___________

Memory 2

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 4

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 6

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 8

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 10

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Mode: ___________

Appendix A-7

VEC-884 Owner's Manual Pre-Set and Memory Filters Settings Chart

Copy this chart and use it to record your Pre-Set and memory filters settings. Use the Talk function to get the frequency values for CF, BW, and/or LR-HR.

Pre-Set RTTY Mode

Mark-Space _____________________ Baud Rate _____________________

Pre-Set AMTOR Mode

Mark-Space _____________________ Baud Rate _____________________

Pre-Set HF PACKET Mode

Mark-Space _____________________ Baud Rate _____________________

Pre-Set PACTOR Mode

Mark-Space _____________________ Baud Rate _____________________

Memory 1

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 3

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 5

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 7

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 9

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Mode: ___________

Mode: ____________

Mode: ___________

Memory 2

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 4

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 6

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 8

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 10

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Mode: ___________

Appendix A-8

VEC-884 Owner's Manual

Pre-Set and Memory Filters Settings Chart

Copy this chart and use it to record your Pre-Set and memory filters settings. Use the Talk function to get the frequency values for CF, BW, and/or LR-HR.

Pre-Set RTTY Mode

Mark-Space _____________________ Baud Rate _____________________

Pre-Set AMTOR Mode

Mark-Space _____________________ Baud Rate _____________________

Pre-Set HF PACKET Mode

Mark-Space _____________________ Baud Rate _____________________

Pre-Set PACTOR Mode

Mark-Space _____________________ Baud Rate _____________________

Memory 1

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 3

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 5

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 7

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 9

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Mode: ___________

Mode: ____________

Mode: ___________

Memory 2

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 4

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 6

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 8

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 10

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Mode: ___________

Appendix A-9

VEC-884 Owner's Manual Pre-Set and Memory Filters Settings Chart

Copy this chart and use it to record your Pre-Set and memory filters settings. Use the Talk function to get the frequency values for CF, BW, and/or LR-HR.

Pre-Set RTTY Mode

Mark-Space _____________________ Baud Rate _____________________

Pre-Set AMTOR Mode

Mark-Space _____________________ Baud Rate _____________________

Pre-Set HF PACKET Mode

Mark-Space _____________________ Baud Rate _____________________

Pre-Set PACTOR Mode

Mark-Space _____________________ Baud Rate _____________________

Memory 1

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 3

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 5

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 7

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 9

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Mode: ___________

Mode: ____________

Mode: ___________

Memory 2

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 4

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 6

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 8

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Memory 10

Operation Conditions/Radio Frequency ________________________________ ________________________________ CF, BW ________________________ LR-HR ________________________

Mode: ___________

Appendix A-10

VEC-884 Owner's Manual

Notes

Appendix A-11

VEC-884 Owner's Manual

Notes

Appendix A-12

Vectronics VEC-884 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual