UBS Axcera 117B User Manual

INSTRUCTION MANUAL

117B

20 WATT VHF HIGH BAND

TRANSLATOR

AXCERA, LLC

103 FREEDOM DRIVE P.O. BOX 525 LAWRENCE, PA 15055-0525 USA

[phone] • FAX [phone]

www.axcera.com • [e-mail]

117B 20 Watt VHF High Band Translator Table of Contents

Table of Contents

1. Introduction:

2. System – 117B:
a. System Description

b. Specifications
c. Installation Procedure
d. System Check Out and Operation Procedure
e. Switch Position and Status for Normal Operation
f. System Alignment Procedure
g. Remote Control Interface Connections
h. Drawings:

1. Block Diagram

2. Interconnect

3. VHF Low Band Receiver Tray:
a. Circuit Description

b. Detailed Alignment Procedure
c. Drawings:

1. Block Diagram

2. Interconnect

4. 20 Watt VHF High Band Upconverter/Amplifier Tray:
a. Circuit Description

b. Detailed Alignment Procedure
c. Drawings:

....................................................................................

..........................................................................

...........................................................................

..........................................................................

...........................................................................

1175-1000

1175-3000
1175-8000

1265-3100
1265-8100

1. Block Diagram

2. Interconnect

5. Subassemblies:

Refer to the subassembly section for the schematics of the boards and subassemblies that
make up the 117B. A drawing list showing the order in which the drawings appear in the
subassembly section is found at the beginning of that section.

6. Maintenance and Harnesses:

This section contains information on proper operation and maintenance of the 117B.

..........................................................................

...........................................................................

1174-3100
1174-8100

- Page 1 of 1 -

117B 20 Watt VHF High Band Translator System Description

The 117B is a 20 Watt High Band VHF Television Translator which operates at a nominal Internally
Diplexed output power of 20 Watts Peak Sync Visual with typically 2 Watts Aural at a -10 dB
Aural/Visual Ratio.

Functionally, it is comprised of a VHF Low Band Receiver Tray (1265-1100) and a 20 Watt VHF
High Band Upconverter/Amplifier Tray {1355-1010 (Low Band), 1355-1011 (Mid Band) or 1355-1012
(High Band)}.

The Receiver Tray receives the Low Band VHF Channel Input at Jack (J1) and converts it to an
Internally Diplexed Visual + Aural IF Output (+0 dBm) at J4. The Visual + Aural IF output of the
Receiver Tray at J4 is fed to J2 the IF Input Jack for the 20 Watt VHF High Band
Upconverter/Amplifier Tray. The Upconverter Section of the Tray mixes the IF with an internally
generated L.O. to produce the VHF High Band Channel Frequency Output. The signal is amplified
and filtered in the Amplifier Section and directed to J4 the RF Output of the Tray. This output
connects to the Antenna for your System.

Jack J7 located on the back of the Upconverter/Amplifier Tray is a 37 Position "D" Remote Interface
Connector which provides the Operator with a connection for Remote Monitoring and Operation of
the Translator.

This manual provides the Technical Specifications of the Translator, along with the Circuit
Description, Alignment Procedure and the Schematics, Block Diagrams, Interconnects and
Replacement Parts Lists necessary for the proper operation and maintenance of the 117B.

VHF Solid State Transmitter / Translator

110A / 110B / 112B / 113B / 114B /

115A / 115B / 117B / 118B / 119B

■ Completely Solid State

■ Designed for unattended operation with

built-in remote control interface

■ Small size – ideal where space is limited

■ Class A amplification up to 20W for

excellent linearity

■ Extensive front panel status and metering

■ Slide out tray assemblies for ease of

maintenance with no extenders

■ BTSC Stereo Ready

VHF Solid State Transmitter / Translator

Visual Performance

Power Output (Peak) 10 / 20 / 50 watts
Output Impedance 50 ohms
Output Connector Type “N”
Frequency Range (low band) 54 to 88 MHz
Frequency Range (high band) 174 to 216 MHz
Carrier Stability (Transmitters

or Translators with FCR) ±250 Hz

Frequency Translation Stability

(Translators) ±250 Hz
Regulation of RF Output Power 3%
Output Variation (over 1 frame) 2%
Sideband Response

-1.25 MHz and below -20 dB

-0.75 to -0.5 MHz +0.5, -2.0 dB

-0.5 to +3.58 MHz ±0.5 dB

3.58 MHz to 4.18 MHz +0.5, -1.0 dB
Freq Response vs. Brightness ±0.5 dB
Visual Modulation Capability 1%

(Transmitters)
Differential Gain 5%
Incidental Phase Modulation ±3°
Linearity (Low Frequency) 5%
Differential Phase ±3°
Signal-to-Noise Ratio 55 dB
2t K-Factor 2%
Envelope Delay

Transmitters Per FCC Standard

Translators ±40 ns
Video Input (Transmitters) 75 ohms
Harmonic Radiation -60 dB
Intermodulation Products -52 dB (red field)
Spurious -50 dB

(>3 MHz from channel edge)
Noise Figure w/input Preamp 6 dB (max.)

(Translators)
Input Dynamic Range -76 to -25 dBm

(Translators)

Aural Performance

Power Output (Average) 1 / 2 / 5 watts
Distortion 0.5%
FM Noise -60 dB
AM Noise -53 dB
Aural to Visual Separation 4.5 MHz, ±100 Hz

(Transmitters)

Composite Audio Input (Transmitters)

Input Level 1V peak, nominal
Input Impedance 75 ohms, unbalanced
Freq (±0.5 dB response) 30 Hz to 120 kHz

Monaural Audio Input (Transmitters)

Input Level 0 to +10 dBm
Input Impedence 600 ohms, balanced
Freq Range (±0.5 dB resp) 30 Hz to 15 kHz
Pre-emphasis 75µs

Subcarrier Input (Transmitters)

Input Level 1V peak, nominal
Input Impedance 75 ohms, unbalanced
Freq Range (±0.5 dB resp) 20 kHz to 120 kHz

General

Operational Temperature Range -30°C to +50°C
Operational Humidity Range 0% to 95%
Altitude up to 8,500 feet
Size (H x W x D)

110A / 115A 7” x 19” x 21”
Transmitters 8.75” x 19” x 21”
(exc 110A / 115A)

Translators 10.5” x 19” x 21”
Weight 30 lbs.
Line Voltage 115/230VAC, ±10%,

1 phase, 50/60 Hz

Power Consumption 250 / 350 / 350 watts

B0001 1101R1-E

117B 20 Watt VHF High Band Translator Installation Procedure

UNPACKING
Please inspect all material thoroughly upon arrival. Axcera certifies that upon leaving our facility

the equipment was undamaged and in proper working order. The shipping container should be
inspected for obvious damage that is indicative of rough handling.

Remove the Cabinet Assembly or if shipped separately, the Receiver Tray, the VHF
Upconverter/Amplifier Tray, the Wire Harness and the Installation Material Kit from the shipping
containers and inspect for damage. Check for dents, scratches or a broken switch, meter or
connector. Remove the top covers from the Trays and again inspect for shipping damage. Extract
all packing material from inside and around the Trays. Check for loose hardware and connectors,
retighten if needed. Any claims against in-transit damage should be directed to the Carrier.

SITE CONSIDERATIONS
There are special considerations which must be made before installing the 117B and this section

will help you plan ahead.
The AC line requirements is an important consideration in Site planning. Each Translator requires a

10 Amp feed.
Another important Site consideration is temperature control. The 117B is rated for operation in an

ambient temperature range of 0° to 45° C. Over temperature problems are far more likely than
under temperature. Over temperature can cause heat related problems such as thermal runaway
or component failure. The Tray contains a Thermal Interlock Circuit that will shut down the
Translator until the temperature drops to an acceptable range.

The Translator requires a cooling system that is adequate for the heat created by the power
dissipation of the Translator. This problem may not surface for many months if the installation is
completed during cool weather, but may suddenly appear during the heat of summer days.

In many cases, a simple heat exhaust system is adequate. A thermostatically controlled fan to
exhaust the heat to the outside works very well if a few guidelines are followed:

1. Check that the fan is large enough. At least 200 CFM per Translator.

2. Place the fan high enough on the wall or in the ceiling where the heat is located.

3. Provide an air intake for cool air. This intake should be on the other side of the room and
low on the wall to allow air to flow over the Translator Cabinet. The intake should also be
large enough to accommodate the capacity of the exhaust fan.

In very hot climates, air conditioning may be required, and cooling capacity must be considered.
The size of the Transmitter Room and the number of Transmitters and/or Translators and other
equipment will determine what size system is required. An HVAC Technician should be consulted.
With both exhaust and air conditioning systems it is better to over estimate the operating capacity
than to under estimate. This provides for a safe operating margin.

Though it is less likely to cause problems, extreme cold should also be anticipated. Extremely low
temperatures may cause condensation inside the Tray due to a large differential between ambient
and internal temperatures. The equipment itself may provide enough heat for normal operation, if
the room is small enough and properly weatherproofed. However, it is better to install a small
heater than to take a chance. The heater will also provide warmth for Technical Personnel if
maintenance or repairs are necessary during the winter months.

INSTALLATION PROCEDURE - CONTINUED
INSTALLATION OF THE TRANSLATOR

- Page 1 of 2 -

117B 20 Watt VHF High Band Translator Installation Procedure

For units that are supplied with a cabinet, remove the Cabinet from the shipping container.
Remove the plastic covering. If the Trays are shipped separately, the shipping material must be
removed from the inside of the Cabinet before the Trays are inserted into the Cabinet. Cut the
cable ties or cord which hold the Tray Harness breakouts to the Tray Slides. Carefully remove the
foam packing material from around the cables, connectors and slides. Do not use a Knife or other
sharp object as these may cut the wires. Slide the Trays into the cabinet, if they are not already
mounted. Check that the cable breakouts for the Trays are not caught in the Trays as they are
slid into place.

If the Trays are shipped mounted in the Cabinet , remove the two metal brackets which hold the
Trays in place during shipment. These are held in place by two screws and must be removed to
allow the Trays to be pulled out for Test.

If the Trays do not slide in and out of the cabinet smoothly, loosen the hardware holding the slides
onto the front of the cabinet and move the Tray up or down to stop it from rubbing. Retighten
after the necessary adjustments have been made.

Secure the small cable retractors, tied to the main harness, to the rear of each Tray by sliding
them into the clip located there. Refer to the rear view of the Trays for more details. Connect
the plugs of the main harness to the corresponding Jack numbers on each Tray, starting with (A2)
the Upconverter/Amplifier Tray. (A1) is the Receiver Tray. (An Example of the numbering is : 1 2
on the cable from the main harness stands for the Receiver Tray A1, AC Input Jack J2).

After the Trays have been installed and all harness connections have been made, connect the
Main AC to the AC Input Box located at the upper, right rear of the Cabinet. 240 VAC, 30 Amp,
#10 AWG, 4 wire is recommended. A Qualified Electrician should do the Main AC Installation. The
AC Input Plug for each Tray should be connected to the AC Outlet Box.

INSTALLATION OF A TRANSLATOR NOT SUPPLIED WITH A CABINET

Two Tray slides are provided for the 1 3/4" Receiver Tray and the 7" VHF Upconverter/Amplifier
Tray. The Receiver Tray should be mounted under the Upconverter/Amplifier Tray. Locate the
Tray slides and install the left slide into the cabinet first. The left side slide is plain with no cable
retractor attached. Mount this slide onto the left side of the cabinet, looking from the rear using
the bolts and nuts provided. Refer to the "Cabinet Mounting Instructions For Tray Slides" drawing
for more details. Check that the slide is level from front to back. NOTE: Allow a spacing of
approximately 5 inches between the end of the stationary section of the slide and the rear
mounting bar of the cabinet to permit normal operation of the cable retractors.

Install the slides onto the right side of the cabinet, looking from the rear. These slides connect
the end bracket, attached to the main harness, to the stationary section of the slide with two #10
hex nuts provided. Now secure the slide by connecting it to the front and rear mounting bars
using #10 bolts and the bar nuts provided.

Connect the plugs from the main harness to the corresponding Jack numbers on each Tray.
(Example: 2 1 means the VHF Upconverter/Amplifier Tray A2, Jack J1). Check that the AC Input
Plugs to the Trays are connected to the AC Outlet Box.

After Installation of the Trays, refer to the Check Out and Operation Procedure for the initial
operation of the Translator.

- Page 2 of 2 -

117B 20 Watt VHF High Band Translator System Check Out and

Operation Procedure

SYSTEM CHECK OUT AND OPERATION PROCEDURE
Connect the output at the "N" Type connector J4 of the 20 Watt VHF Upconverter/Amplifier Tray

to a suitable load or the Antenna for your System. Connect the Low Band VHF Channel RF Input
Signal to Jack J1 located on the rear panel of the Receiver Tray.

Switch the AC Main Circuit Breaker on. Switch On the On/Off Power Switches located on the
Receiver Tray and the VHF Upconverter/Amplifier Tray and observe that the switches light,
indicating AC is present to that Tray. Flip the Operate/Standby Mode Switch located on the VHF
Upconverter/Amplifier Tray and confirm that the LED indicators will also switch. Switch the
Translator to Standby.

The Translator Control (Automatic/Manual) Switch S3, located on the front panel of the VHF
Upconverter/Amplifier Tray, switches the Translator between the Automatic and Manual mode of
operation. In Automatic, the Translator will revert to Standby if the input RF signal is lost. During
Testing of the Translator, Switch S3 to Manual, this will keep the Translator from going to Standby
if the Input RF is removed. Normal Operation is with the switch in the Manual Mode.

Slide the Upconverter/Amplifier Tray out and remove the top cover. Check that switches S1 (ALC)
and S2 (AGC), located on (A10) the ALC/AGC Board (1067-1116) are both in the Automatic
position. Confirm that S1 on (A11) the Linearity Corrector Board (1161-1116) is Enabled. Switch
the Translator to Operate. The Amplifier Status LED (DS4) will light indicating normal current draw
by (A17-A2) the High Band VHF Amplifier Board (1174-1101). The Green Thermal Interlock LED
(DS3) will light indicating that the temperature within the Tray is Normal. Switch the Front Panel
Meter Selector Switch to the Power Supply Voltage position and confirm a reading of +24 VDC, the
voltage produced by (A3) the Switching Power Supply Assembly.

Turn the Front Panel Meter Selector Switch to the % Visual Power Position and verify a reading,
normally 100%, which is the same value as written on the Test Data Sheet for the Translator.
Turn the Meter Selector Switch to the % Aural Power Position and verify a reading which is the
same value as written on the Test Data Sheet for the Translator. The Aural/Visual Ratio is
typically set to 10 dB at the factory. Turn the switch to the % Reflected Power Position and
verify the Test Data Sheet Reflected Power value, <10%. The ALC Reference Voltage Position
should read 2 Volts. The AGC Detector Voltage Position should read .3 Volts.

If the Translator has completed the above System Check Out Procedure, replace the lids of the
Trays and slide them back into place. If a problem occurred in a Tray, refer to the Detailed
Alignment Procedure in that Tray Section of the Manual for more information.

Check that the RF Input Signal is connected to the Receiver Tray. Check that the RF output of
the 20 Watt VHF High Band Upconverter/Amplifier Tray is connected to the antenna for your
System. Check that the Automatic/Manual Switch located on the front panel of the
Upconverter/Amplifier Tray is switched to the Manual position.

You are now ready for the normal operation of the Translator. Set-up of the linearity correctors
are described in the System Alignment Procedure which follows.

- Page 1 of 1 -

117B 20 Watt VHF High Band Translator Switch Position and Status

for Normal Operation

Switch Position and Status for Normal Operation

VHF Low Band Receiver Tray

(A12) IF ALC Board (1109-1402) S1 switched to ALC position.

20 WATT VHF High Band Upconverter/Amplifier Tray

(A10) ALC/AGC Board (1067-1116) S1 switched to ALC position

S2 switched to AGC position
DS2 not lit (Video is Present)
DS3 not lit (No ALC Fault)
DS4 not lit (No AGC Fault)

DS5 not lit (No RF Mute)
(A11) Linearity Corrector Board (1161-1116) S1 switched to Correction in, Enable
(A7) Transmitter Control Board (1161-1109) S1 switched to Modulator, DS5 lit.

DS1 not lit (RF Input is present to the

Receiver Tray). May be lit all the time if

Receiver Tray not used.

DS2 not lit (Video Input to

Upconverter/Amplifier Tray is present).

DS3 not lit (Video Input is present to the

Modulator Tray. May be lit constantly if

Optional Modulator Tray not present.
Front Panel Auto/Manual Switch (S3) Manual position
Front Panel Meter Selector Switch (S1) Selects metering: % Visual Output Power, %

Aural Output Power, % Reflected Power,

Power Supply Voltage, ALC Reference Voltage

and AGC Detector Voltage.

- Page 1 of 1 -

117B 20 Watt VHF High Band Translator System Alignment Procedure

The Translator has been factory aligned and should not require adjustment to obtain normal
operation. For a Detailed Alignment Procedure of each Tray, refer to the Receiver Tray or the 20
Watt Upconverter/Amplifier Tray section of this Manual.

SYSTEM SET UP
The system set-up includes adjustment of linearity to compensate for any amplifiers nonlinear

responses. The Translator should be switched On initially into a 20 Watt dummy load to verify that
the system is functioning properly.

In the VHF Upconverter/Amplifier Tray, check that the ALC Auto/Manual Switch (S1), located on
(A10) the ALC/AGC Board (1067-1116), is in Auto. Switch the On/Off Circuit Breakers located on
the front panels of the Receiver and the 20 Watt Upconverter/Amplifier to the On position. Switch
the Translator to Operate and adjust the ALC Reference Pot (R47), or (R2) the Front Panel Power
Adjust, to obtain a Detected IF Output Voltage Level of +2.0 VDC at TP3 of the ALC/AGC Board.
The Front Panel Meter in the ALC Reference Voltage position should also read +2.0 VDC. Switch
the ALC Auto/Manual Switch (S1) to Manual ALC and adjust the Manual ALC Pot (R17) to obtain a
Detected IF Output Voltage Level of +2.0 VDC at TP3 of the ALC/AGC Board. Switch the ALC
Auto/Manual Switch (S1) to Auto ALC.

In the VHF Upconverter/Amplifier Tray, check that the AGC Switch (S2), located on (A10) the
ALC/AGC Board (1067-1116) is in Auto. Preset the AGC Auto Gain Pot (R96) and the AGC Manual
Gain Pot (R101) to minimum (CCW). Switch the Front Panel Automatic/Manual Switch to Manual.
Switch the front panel Metering Switch, located on the 20 Watt Upconverter/Amplifier Tray, to the
% Visual Output Power position and adjust the AGC Auto Gain pot (R96) located on (A10) the
ALC/AGC Board (1067-1116) to 100% on the meter. Switch the AGC Switch (S2) to the Manual
Position and adjust the AGC Manual Gain pot (R101), located on the ALC/AGC Board, also for 100%
on the meter. Switch S2 back to Automatic. The Front Panel Meter of the Upconverter/Amplifier
Tray in the AGC Detector Voltage position should read +.3 VDC, but the exact values are written
on the Final Test Data Sheet for your System.

Connect a Demodulator and Oscilloscope or other monitoring equipment to monitor the differential
gain and differential phase of the output signal. If a synchronous demodulator having a quadrature
video output is available, it may be employed with an X-Y Oscilloscope to display incidental carrier
phase modulation (ICPM). As shipped, the Translator was preset to include linearity (gain vs.
level) predistortion which was adjusted to compensate for the corresponding non-linear distortions
of the solid state amplifier devices in the Translator. Switch S1 located on (A11) the Linearity
Corrector Board (1161-1116), to the On position.

SYSTEM SET UP OF LINEARITY
The IF linearity correction function consists of three non-linear cascaded stages, each having an

adjustable magnitude and a threshold, cut -in point. The threshold adjustment determines at what
IF signal level the corresponding corrector stage begins to increase gain. The magnitude
adjustment determines the amount of gain change for the part of the signal which exceeds the
corresponding threshold point. Because the stages are cascaded, the order of correction is
important.

The first stage should cut -in nearest the white level, with the cut-in point of the second stage
moving toward black, with the last stage primarily stretching sync. Linearity Corrector Board pots
R3, R13 and R23 control the overall gain of each stage. They were preset during Final Test at the
Factory and should not require adjustment. If moved accidentally, typical settings are R3, R13 and
R23 mid-range.

SYSTEM SET UP OF LINEARITY - CONTINUED

- Page 1 of 2 -