Tait TEL0042 User Manual

M820-00 1

T820 Series II

Base Station Equipment

66-88MHz

Tuning & Adjustment Manual

July 2000

M820-00-2TA

Copyright TEL 01/04/00

2 M820-00

T800

T800

Head Office
New Zealand

Tait Electronics Ltd
558 Wairakei Road
P.O. Box 1645
Christchurch
New Zealand
Phone: [phone]
Fax: [phone]

Radio Systems Division

535 Wairakei Road
P.O. Box 1645
Christchurch
New Zealand
Phone: [phone]
Fax: [phone]

Australia

Tait Electronics (Aust) Pty Ltd
186 Granite Street
Geebung
Queensland 4034
P. O . Bo x 6 79
Virginia
Queensland 4014
Australia
Phone: [phone]
Toll Free: 1 800 077 112
Fax: [phone]

Canada

Tait Mobile Radio Inc.
Unit 5, 158 Anderson Avenue
Markham
Ontario L6E 1A9
Canada
Phone: [phone]
Toll Free: 1 800 890 8248
Fax: [phone]

France

Ta i t F r a n c e S a r l
2 Avenue de la Cristallerie
92 316 Sèvres, Cedex
France
Phone: [phone]
Fax: [phone]

Germany

Tait Europe Limited
Geschäftsstelle Deutschland
Fürther Str. 27
D-90429 Nürnberg
Germany
Phone: [phone]
Fax: [phone]

Hong Kong

Tait Mobile Radio (HK) Ltd
Unit 2216, North Tower
Concordia Plaza
No. 1 Science Museum Road
Tsim Sha Tsui East
Kowloon
Phone: [phone]
Fax: [phone]

New Zealand

Tait Communications Ltd
Unit 4, 75 Blenheim Road
P. O. Bo x 1 1 8 5
Christchurch
Phone: [phone]
Fax: [phone]

Ta i w a n

Tait Mobile Radio (Taiwan) Ltd
5Fl., No. 159, Keelung Rd
Sec. 1
Tai p ei 110
Tai w a n
Phone: [phone]
Fax: [phone]

Thailand

Tait Mobile Radio Ltd
14/1 Suwan Tower
Third Floor
North Sathorn Road
Soi Saladaeng 1
Bangrak
Bangkok 10500
Thailand
Phone: [phone]
Fax: [phone]

United Kingdom

Tait Europe Ltd
Ermine Business Park
Ermine Road
Huntingdon
Cambridgeshire PE18 6YA
United Kingdom
Phone: [phone]
Fax: [phone]

USA

Tait Electronics (USA) Inc.
9434 Old Katy Road
Suite 110
Houston
Texas 77055
USA
Phone: [phone]
Toll Free: 1 800 222 1255
Fax: [phone]

Internet

http://www.taitworld.com

Beijing

Tait Mobile Radio (HK) Ltd
Beijing Representative Office
Room 610, Tower 2
Beijing Henderson Centre
No. 18 Jianguomennei Da Jie
Doncheng District
Beijing
China 100005

Singapore

Tait Electronics (Far East) Pte Ltd
4 Leng Kee Road
SIS Building #05-11A
Singapore 159088
Phone: [phone]
Fax: [phone]

01/04/00 Copyright TEL

M820-00 3

About This Manual

Scope This manual contains general, technical, tuning and adjustment

information on T820 Series II 25W and 50W base stations which
comprise the following equipment:

25W base station T825 receiver

T826 25W transmitter

50W base station T825 receiver

T827 exciter
T828 50W power amplifier

PCB Information PCB information is provided for all current issue PCBs, as well

as all previous issue PCBs manufactured in production quanti­ties, and is grouped according to PCB. Thus, you will find the
parts list, grid reference index (if necessary), PCB layouts and
circuit diagram(s) for each individual PCB grouped together.

Errors If you find an error in this manual, or have a suggestion on how

it might be improved, please do not hesitate to contact Customer
Support, Tait Electronics Ltd, Christchurch, New Zealand (full
contact details are on page 2).

Updating Equipment And Manuals

In the interests of improving performance, reliability or servicing, Tait Electronics Ltd
reserve the right to update their equipment and/or manuals without prior notice.

Copyright

All information contained in this manual is the property of Tait Electronics Ltd. All
rights are reserved. This manual may not, in whole or part, be copied, photocopied,
reproduced, translated stored or reduced to any electronic medium or machine readable
form without prior written permission from Tait Electronics Ltd.

Ordering Tait Service Manuals

You can order additional copies of this manual from your nearest Tait Dealer or Cus­tomer Service Organisation. When ordering, make sure you quote the correct Tait prod­uct code ("M" number). Note that only the latest issue of the manual will be available
for order.

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4 M820-00

Tab le Of Co n t e n ts

This manual is divided into five parts as listed below, with each part being further sub­divided into sections. There is a detailed table of contents at the start of each part and/
or section.

Part Title

A Introduction To Servicing

B T825 Receiver

C T826 Transmitter & T827 Exciter

D T828 Power Amplifier

E T820 VCO PCB Information

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M820-00 AI

Part A Introduction To Servicing

This part of the manual is divided into the sections listed below. These sections provide
some general and advisory information on servicing procedures, and a brief history of
PGM800Win programming software.

Section Title Page

1

1.1

1.2

1.3

1.4

2

2.1

2.2

2.3

2.3.1

2.3.2

2.4

2.5

3

3.1

3.1.1

3.1.2

General

Additional Technical Information

Caution: CMOS Devices

Caution: Aerial Load

Caution: Beryllium Oxide & Power Transistors

Mechanical

Torx Recess Head Screws

Pozidriv & Philips Recess Head Screws

Disassembly/Reassembly

Receivers/Exciters/Transmitters
Power Amplifiers

Cover Screw Torques

Chassis & Cover Compatibility

Component Replacement

Leaded Components

Desoldering Iron Method
Component Cutting Method

1.1

1.1

1.1

1.2

1.2

2.1

2.1

2.2

2.3

2.3

2.3

2.3

2.4

3.1

3.1

3.1

3.1

3.2

3.3

4

4.1

4.2

Surface Mount Devices

Cased Mica Capacitors

Software History

PGM800Win V1.0

PGM800Win V2.00

Figure Title Page

1.1

1.2

2.1

2.2

2.3

Typical Product Code & Serial Number Labels

Typical Anti-static Bench Set-up

Torx Screw Identification

Pozidriv & Philips Screw & Screwdriver Identification

Identification Of New-Design Chassis & Covers

3.2

3.2

4.1

4.1

4.1

1.1

1.2

2.1

2.2

2.4

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AII M820-00

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M820-00 General A1.1

1 General

1.1 Additional Technical Information

If you have any questions about this manual or the equipment it describes, please con­tact your nearest Tait Dealer or Customer Service Organisation. If necessary, you can
get additional technical help from Customer Support, Radio Systems Division, Tait Elec­tronics Ltd, Christchurch, New Zealand (full contact details are on page 2).

When requesting information, please quote either the manual product code (e.g.
M820-00-200), or the equipment product code and serial number which are printed on a
label on the back of the product (as shown in Figure 1.1).

this area used for regional
Type Approval information

T838-10-0000

Rev 1

900000

Tait Electronics Limited
Made in New Zealand

Figure 1.1 Typical Product Code & Serial Number Labels

product code
serial number

T835-10-0000 Rev 1

Tait Electronics Limited
Made in New Zealand

900000

If you require information about a particular PCB, please quote the full PCB internal
part number (IPN) which is screen printed onto the top side of the board (refer to the
appropriate PCB Information section in this manual for more details).

1.2 Caution: CMOS Devices

This equipment contains CMOS Devices which are susceptible to damage from static
charges. Care when handling these devices is essential. For correct handling proce­dures refer to the manufacturers' data books, e.g. Philips data books covering CMOS
devices, or Motorola CMOS data books, Section 5 'Handling', etc.

An anti-static bench kit (refer to Figure 1.2) is available from Tait Electronics Ltd under
the following product codes:

• KS0001 - 1 conductive rubber bench mat

- 1 earth lead to connect the mat to ground

• KS0004 - 1 wrist strap.

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A1.2 General M820-00

conductive

wrist strap

to building earth
(not mains earth)

Figure 1.2 Typical Anti-static Bench Set-up

1.3 Caution: Aerial Load

conductive rubber

bench mat

The equipment has been designed to operate safely under a wide range of aerial loading
conditions. However, we strongly recommend that the transmitter should always be
operated with a suitable load to prevent damage to the transmitter output power stage.

1.4 Caution: Beryllium Oxide & Power Transistors

The RF power transistors in current use all contain some beryllium oxide. This sub­stance, while perfectly harmless in its normal solid form, can become a severe health
hazard when it has been reduced to dust. For this reason the RF power transistors
should not be broken open, mutilated, filed, machined, or physically damaged in any
way that can produce dust particles.

01/04/00 Copyright TEL

M820-00 Mechanical A2.1

2 Mechanical

2.1 Torx Recess Head Screws

Torx recess head screws are becoming the standard screw head type in all T800 Series II
equipment, with Pozidriv and Philips recess head screws being used in fewer applica­tions.

The Torx recess head has the advantage of improved screwdriver tip location, reducing
the chances of screw head damage caused by the driver tip rotating within the recess. In
addition, using a ball-tip Torx screwdriver allows you to drive a Torx head screw with
the driver on a slight angle, which can be useful in situations where access is restricted.

It is important that you use the correct Torx screwdriver tip:

M3 screws - T10
M4 screws - T20.

Figure 2.1 below shows a typical Torx recess head screw (actual hardware may differ
slightly from this illustration due to variations in manufacturing techniques).

"star" shaped recess with
six internal notches

Figure 2.1 Torx Screw Identification

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A2.2 Mechanical M820-00

2.2 Pozidriv & Philips Recess Head Screws

Pozidriv and Philips recess head screws will continue to be used in T800 Series II equip­ment in a few special applications. It is important that you use the correct type and size
screwdriver for each screw type to avoid damaging the screw head.

It is particularly important that you do not use Philips screwdrivers on Pozidriv screw
heads as the tapered driving flutes of the Philips screwdriver do not engage correctly
with the parallel-sided slots in the Pozidriv screw head. This can result in considerable
damage to the screw head if the screwdriver tip turns inside the recess.

Note:

If you find you need excessive downwards pressure to keep the screwdriver
tip in the Pozidriv screw head, you are probably using the wrong type and/
or size screwdriver.

Figure 2.2 below shows the main differences between typical Pozidriv and Philips screw
heads and screwdriver tips (actual hardware may differ slightly from these illustrations
due to variations in manufacturing techniques).

Pozidriv Philips

internal notches

no special markings

"star" markings
between slots

slots with parallel sides

slots with tapered sides

driving flutes with
parallel sides

driving flutes with
tapered sides

ridges between
driving flutes

Figure 2.2 Pozidriv & Philips Screw & Screwdriver Identification

01/04/00 Copyright TEL

M820-00 Mechanical A2.3

2.3 Disassembly/Reassembly

2.3.1 Receivers/Exciters/Transmitters

To carry out alignment or change option links, you need to remove only the top cover,
i.e. the one adjacent to the front panel handle and on the opposite side to the main
D-range connector (D-range 1/PL100).

You need to remove the bottom cover to:

• access transmitter RF power transistors and many SMD components

• change solder blob links

• fit test leads to circuit block access points.

2.3.2 Power Amplifiers

You should carry out the tuning and power output level setting procedures with the
cover on.

2.4 Cover Screw Torques

Receivers/Exciters/Transmitters .. 1.36Nm/12in.lbf.

Power Amplifiers .. 0.9Nm/8in.lbf.

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A2.4 Mechanical M820-00

2.5 Chassis & Cover Compatibility

The chassis and covers used in T800 Series II modules incorporate a number of design
changes to improve Electro-Magnetic Compatibility (EMC) performance. It is impor­tant that only the new-design covers are fitted to the new chassis to ensure correct
mechanical fit and continued compliance with appropriate EMC Type Approval regula­tions.

Figure 2.3 below shows some of the main features which can be used to identify the
new-design chassis and covers.

Chassis

←Top View

loom channel in
top of walls

Rear View

4 holes in
rear panel

→

groove in top
of rear wall

Top Cover

provision for mounting speaker
(future development)

ridge on top
of rear wall

Bottom Cover

additional walls

Figure 2.3 Identification Of New-Design Chassis & Covers

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M820-00 Component Replacement A3.1

3 Component Replacement

3.1 Leaded Components

Whenever you are doing any work on the PCB that involves removing or fitting compo­nents, you must take care not to damage the copper tracks. The two satisfactory meth­ods of removing components from plated-through hole (PTH) PCBs are detailed below.

Note:

The first method requires the use of a desoldering station, e.g. Philips SBC
314 or Pace MBT-100E.

3.1.1 Desoldering Iron Method

Place the tip over the lead and, as the solder starts to melt, move the tip in a circu­lar motion.

Start the suction and continue the movement until 3 or 4 circles have been com­pleted.

Remove the tip while continuing suction to ensure that all solder is removed from
the joint, then stop the suction.

Before pulling the lead out, ensure it is not stuck to the plating.

If the lead is still not free, resolder the joint and try again.

Note:

The desoldering iron does not usually have enough heat to desolder leads
from the ground plane. Additional heat may be applied by holding a sol­dering iron on the tip of the desoldering iron (this may require some addi­tional help).

3.1.2 Component Cutting Method

Cut the leads on the component side of the PCB.

Heat the solder joint
out from the component side: do

Fill the hole with solder and then clear with solderwick.

Copyright TEL 01/04/00

sufficiently

to allow

not

easy

use undue force.

removal of the lead by drawing it

A3.2 Component Replacement M820-00

3.2 Surface Mount Devices

Caution: Surface mount devices (SMDs) require special storage, handling,

removal and replacement techniques. This equipment should be serv­iced only by an approved Tait Dealer or Customer Service Organisa­tion equipped with the necessary facilities. Repairs attempted with
incorrect equipment or by untrained personnel may result in perma­nent damage. If in doubt, contact your nearest Tait Dealer or Customer
Service Organisation.

3.3 Cased Mica Capacitors

Cased mica capacitors can be removed by heating the top with a heavy-duty soldering
iron and gently lifting the capacitor off the PCB with a solder-resistant spike or equiva­lent.

01/04/00 Copyright TEL

M820-00 Software History A4.1

4 Software History

28/06/96 PGM800Win Version 1.0
18/08/97 PGM800Win Version 2.00

4.1 PGM800Win V1.0

PGM800Win V1.0 is different in concept from DOS versions of PGM800 in that it is Win-

1

dows
PGM800.

The major changes are outlined below:

based. It also includes many new and improved features over DOS versions of

• The Windows

• PGM800Win includes several new radio models which are not programmable
with DOS versions of PGM800.

• Out of range frequencies will result in warning messages and will not be accepted
for entry into the standard library module. User defined modules can be created,
however, allowing variation from the standard library module.

• Channel numbers default to 0-127 to match the EPROM memory locations. How­ever, the user can change this setting so that the channel numbers run from 1-128
to suit his/her particular needs.

Note:

The data files produced by BASEPROG V1.0 and all DOS versions of
PGM800 are still compatible with PGM800Win V1.0.

 environment makes data entry and editing significantly easier.

4.2 PGM800Win V2.00

PGM800Win V2.00 is an upgraded and expanded version of PGM800Win V1.0. It has
been developed specifically for T800 Series II base stations, but retains the ability to pro­gram Series I equipment.

The major changes are outlined below:

• PGM800Win V2.0 will program T800 Series II base station modules via serial com­munications.

• Deviation and reference modulation settings are written automatically to the
radio.

1. Windows is a registered trademark of the Microsoft Corporation.

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A4.2 Software History M820-00

• Extra information that is not stored in the radio (but which is still relevant to the
radio) can be saved to a file on disk (e.g. note field, auxiliary pin names, etc.).

Note:

The data files produced by BASEPROG V1.0, all DOS versions of PGM800,
and PGM800Win V1.0 are still compatible with PGM800Win V2.00.

01/07/00 Copyright TEL

M820-00 BI

Part B T825 Receiver

This part of the manual is divided into six sections, as listed below. There is a detailed
table of contents at the start of each section.

Section Title

1 General Information

2 Circuit Operation

3 Initial Tuning & Adjustment

4 Functional Testing (not available for Tuning & Adjustment manual)

5 Fault Finding (not available for Tuning & Adjustment manual)

6 PCB Information

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BII M820-00

01/07/00 Copyright TEL

M820-00 T825 General Information B1.1

1 T825 General Information

This section provides a brief description of the T825 receiver, along with detailed speci­fications and a list of types available.

The following topics are covered in this section.

Section Title Page

1.1 Introduction 1.3

1.2

1.2.1

1.2.2

1.2.3

1.2.4

1.2.4.1

1.2.4.2

1.2.4.3

1.2.5

1.2.6

1.2.6.1

1.2.6.2

1.2.6.3

1.3 Product Codes 1.10

1.4 Standard Product Range 1.11

Specifications

Introduction

General

RF Section

Audio Section

General
CTCSS
Mute Operation

Microcontroller

Tes t Sta n da rd s

European Telecommunication Standard (ETS)
DTI CEPT Recommendation T/R-24-01
Telecommunications Industry Association

1.4

1.4

1.5

1.5

1.7

1.7

1.7

1.8

1.8

1.8

1.8

1.9

1.9

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B1.2 T825 General Information M820-00

01/04/00 Copyright TEL

M820-00 T825 General Information B1.3

1.1 Introduction

The T825 is a high performance microprocessor controlled FM base station receiver
designed for single or multichannel operation in the 66 to 88MHz frequency range

The receiver is a dual conversion superhet with a synthesised local oscillator. The first
IF is 10.7MHz, allowing exceptionally high spurious signal rejection to be achieved in
the receiver front end. The second IF section (455kHz) combines amplitude limiting,
detection and RSSI within a single integrated circuit. This IC also drives a noise level
detector for gating the audio output. RSSI can also be used to drive a carrier mute for
audio output gating (link selectable).

The audio section output can be adjusted to deliver >+10dBm to a 600 ohm balanced
output, and 1W to a local monitor speaker. A flat or de-emphasised audio response is
link selectable.

The synthesiser frequency is programmed via the serial communications port. Eight
channel select lines are accessible via an optional D-range connector (D-range 2 ­T800-03-0000) at the rear of the set.

All components except those on the VCO board are mounted on a single PCB. This is
secured to a die-cast chassis which is divided into compartments to individually shield
each section of circuitry. Access to both sides of the main PCB is obtained by removing
each of the two chassis covers. There is provision within the chassis to mount small
option PCBs.

1

.

The front panel controls include gating sensitivity, line level, monitor volume and a
monitor mute switch.

The T825 has a width of 60mm and occupies a single space in a Tait rack frame, which
has the ability to accommodate up to seven standard modules.

1. Although capable of operating over the 66-88MHz frequency range, the T825 has a
2MHz switching range (see Section 1.2.3 and Section 3.1).

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B1.4 T825 General Information M820-00

1.2 Specifications

1.2.1 Introduction

The performance figures given are minimum figures, unless otherwise indicated, for
equipment tuned with the maximum switching range and operating at standard room

temperature (+22°C to +28°C) and standard test voltage (13.8V DC).

Where applicable, the test methods used to obtain the following performance figures
are those described in the EIA and ETS specifications. However, there are several
parameters for which performance according to the CEPT specification is given. Refer
to Section 1.2.6 for details of test standards.

Details of test methods and the conditions which apply for Type Approval testing in all
countries can be obtained from Tait Electronics Ltd.

The terms "wide bandwidth" and "narrow bandwidth" used in this and following sec­tions are defined in the following table.

Channel Spacing

Wide Bandwidth 25kHz ±5.0kHz 15.0kHz

Narrow Bandwidth 12.5kHz ±2.5kHz 7.5kHz

Sensitivity and distortion figures are stated for both de-emphasised and flat audio
responses under standard operating conditions. Note that the sensitivity and distortion
figures will be degraded when flat audio is selected.

Link PL210 Link PL220

De-emphasised Audio 1-2 2-3

Flat Audio 2-3 1-2

Modulation

100% Deviation

Receiver

IF Bandwidth

01/04/00 Copyright TEL

M820-00 T825 General Information B1.5

1.2.2 General

Number Of Channels .. 128 (standard)

Supply Voltage:

Operating Voltage .. 10.8 to 16V DC
Standard Test Voltage .. 13.8V DC
Polarity .. negative earth only
Polarity Protection .. crowbar diode

Supply Current:

Standby .. 350mA
Full Audio .. 750mA

Operating Temperature Range .. -30°C to +60°C

Dimensions:

Height .. 183mm
Width .. 60 mm
Length .. 322mm

Weight .. 2.13kg

1

1.2.3 RF Section

Frequency Range .. 66-88MHz

Type .. dual conversion superheterodyne

Frequency Increment .. 5 or 6.25kHz

Switching Range .. 2MHz (i.e. ±1MHz from the centre

frequency)

Input Impedance .. 50 ohms

Frequency Stability .. ±2.5ppm, -30°C to +60°C

(see also Section 1.4) (±1ppm available for special

applications)

Signal Strength Indicator .. -115dBm to -70dBm, 3.5 to 6.5V
(RSSI) at approx. 15dB/V

1. Additional channels may be factory programmed. Contact your nearest Tait Dealer or
Customer Service Organisation.

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B1.6 T825 General Information M820-00

IF Amplifiers:

Frequencies .. 10.7MHz and 455kHz
Bandwidths-

Narrow Bandwidth (NB) .. 7.5kHz
Wide Bandwidth (WB) .. 15kHz

Sensitivity (De-emphasised Response):

Single Channel .. -117dBm
Bandspread (12dB Sinad) .. -115dBm (across switching range)

Sensitivity (Flat Response):

Single Channel .. -111dBm
Bandspread (12dB Sinad) .. -109dBm (across switching range)

Signal+Noise To Noise Ratio (Typical):

De-emphasised

RF Level -107dBm (CEPT) .. 30dB (WB) 25dB (WB)

25dB (NB) 20dB (NB)

Flat

RF Level -83dBm (CEPT) .. 50dB (NB) 45dB (NB)

RF Level -57dBm (EIA) .. 55dB (WB) 52dB (WB)

Selectivity:

Narrow Bandwidth (±12.5kHz) .. 90dB (CEPT)
Wide Bandwidth (±25kHz) .. 95dB (EIA)

Offset Selectivity (Canada only) .. 20dB

Spurious Response Attenuation .. 100dB EIA (typical)

Intermodulation Response Attenuation:

Narrow Bandwidth .. 80dB CEPT (typical)
Wide Bandwidth .. 85dB EIA (typical)

Blocking .. 100dB

Co-channel Rejection .. 6dB

Amplitude Characteristic .. 3dB

Spurious Emissions:

Conducted .. -90dBm to 4GHz
Radiated .. -57dBm to 1GHz

-47dBm to 4GHz

01/04/00 Copyright TEL

M820-00 T825 General Information B1.7

1.2.4 Audio Section

1.2.4.1 General

Outputs Available .. line and monitor

Frequency Response .. flat or de-emphasised (750µs)

(link selectable)

Flat Response:

Bandwidth .. 67 to 3400Hz
Response .. within +1, -2dB of output level

at 1kHz

De-emphasised Response:

Bandwidth .. 300 to 3400Hz
Response .. within +1, -3dB of a 6dB/octave

de-emphasis characteristic (ref. 1kHz)

Line Output:

Power .. adjustable to >+10dBm
Load Impedance .. 600 ohms
Distortion (@ -70dBm signal level):

De-emphasised

Wide Bandwidth .. ≤2% ≤2%
Narrow Bandwidth .. ≤2% ≤4%

Monitor Output:

Power .. 1W
Speaker Impedance .. 4 ohms

Distortion .. ≤3%

(@ -70dBm signal level, links set to de-emphasis)

1.2.4.2 CTCSS

Linkable High Pass Filter:

Bandwidth .. 350 to 3400Hz
Response .. within +1, -3dB of level at 1kHz
Hum And Noise .. 30dB min. at 250.3Hz
(1kHz at 60% system deviation 35dB typical (67 to 240Hz)
CTCSS at 10% system deviation)

Flat

Ton e De t e ct :

Tone Squelch Opening .. better than 6dB sinad

3dB sinad at 250.3Hz (typical)
4dB sinad at 100Hz (typical)

Tone Detect Bandwidth .. ±2.1Hz accept (typical)

±3.0Hz reject (typical)

Response Time .. 150ms open and close (typical)

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B1.8 T825 General Information M820-00

1.2.4.3 Mute Operation

Systems Available .. noise mute and carrier mute

Noise Mute:

Operating Range .. 6-20dB sinad
Hysteresis .. 1.5 to 6dB
Threshold .. adjustable to -105dBm
Opening Time .. 20ms
Closing Time .. 50ms

Carrier Mute (Optional):

Operating Range .. -115 to -80dBm
Hysteresis .. 2 to 10dB
Opening Time .. 5ms
Closing Time .. 50ms

Note:

The opening and closing times given above are for the standard set-up
(SL210 linked and SL220 not linked - refer to Section 3.8).

1.2.5 Microcontroller

Auxiliary Ports:

Open Drain Type .. capable of sinking 2.25mA via 2k2Ω

max. .. 5V

V

ds

1.2.6 Test Standards

Where applicable, this equipment is tested in accordance with the following standards.

1.2.6.1 European Telecommunication Standard

ETS 300 086 January 1991

Radio equipment and systems; land mobile service; technical characteristics and test
conditions for radio equipment with an internal or external RF connector intended pri­marily for analogue speech.

ETS 300 113 March 1996

Radio equipment and systems; land mobile service; technical characteristics and test
conditions for radio equipment intended for the transmission of data (and speech) and
having an antenna connector.

ETS 300 219 October 1993

Radio equipment and systems; land mobile service; technical characteristics and test
conditions for radio equipment transmitting signals to initiate a specific response in the
receiver.

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M820-00 T825 General Information B1.9

ETS 300 279 February 1996

Radio equipment and systems; electromagnetic compatibility (EMC) standard for pri­vate land mobile radio (PMR) and ancillary equipment (speech and/or non-speech).

1.2.6.2 DTI CEPT Recommendation T/R-24-01

Annex I: 1988

Technical characteristics and test conditions for radio equipment in the land mobile
service intended primarily for analogue speech.

Annex II: 1988

Technical characteristics of radio equipment in the land mobile service with regard to
quality and stability of transmission.

1.2.6.3 Telecommunications Industry Association

ANSI/TIA/EIA-603-1992

Land mobile FM or PM communications equipment measurement and performance
standards.

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B1.10 T825 General Information M820-00

1.3 Product Codes

The three groups of digits in the T820 Series II product code provide information about
the model, type and options fitted, according to the conventions described below.

The following explanation of T820 Series II product codes is not intended to suggest that
any combination of features is necessarily available in any one product. Consult your
nearest Tait Dealer or Customer Service Organisation for more information regarding
the availability of specific models, types and options.

Model

The Model group indicates the basic function of the product, as follows:

T82X

-XX-XXXX T825 receiver
T826 25W transmitter
T827 exciter
T828 50W power amplifier

Type

The Type group uses two digits to indicate the basic RF configuration of the product.

The first digit in the Type group designates the frequency range:

T82X-X

The second digit in the Type group indicates the channel spacing:

T82X-XX

X-XXXX ’1’ for 66-88MHz

-XXXX ’0’ for wide bandwidth (25kHz)
’5’ for narrow bandwidth (12.5kHz)

Options

T82X-XX-XXXX The Options group uses four digits and/or letters to indicate

any options that may be fitted to the product. This includes
standard options and special options for specific customers.
’0000’ indicates a standard Tait product with no options fitted.
The large number of options precludes listing them here.

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M820-00 T825 General Information B1.11

1.4 Standard Product Range

The following table lists the range of standard T825 types (i.e. no options fitted) availa­ble at the time this manual was published. Consult your nearest Tait Dealer or Cus­tomer Service Organisation for more information.

Frequency Range (MHz)

IF Bandwidth (kHz) 7.5 15

b

TCXO

Receiver Type: T825- 15-0000 10-0000

a. Selectable by solder links - refer to Section 3.7.

b. A TCXO with a stability of ±1ppm (0°C to +60°C) is

±2.5ppm -30°C to +60°C

available to suit specific requirements. Contact your
nearest authorised Tait Dealer or Customer Service
Organisation for further details.

a

66-88

••

You can identify the receiver type by checking the product code printed on a label on
the rear of the chassis (Figure 1.1 in Part A shows typical labels). You can further verify
the receiver type by checking the placement of an SMD resistor in the table that is screen
printed onto the PCB (refer to Section 6.1 for more details).

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B1.12 T825 General Information M820-00

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