Ericsson LBI-31511B, Maintenance Manual, Page: 8 / 18

TRANSMITTER ALIGNMENT
Before bench testing the radio, be sure or the output voltage characteristics of your bench power supply.
To protect the transmitter power output transistors from possible instant destruction, the following input voltages must not
be exceeded:
Transmitter unkeyed: 20 Volts
Transmitter keyed (50 ohms resistive load): 18 Volts
Transmitter Keyed (no load or non-resistive load): 14 Volts
These voltages are specified at the normal vehicle battery terminals of the radio and take the voltage drop of standard cables
into account. The voltage limits shown for a non-optimum load is for "worst case" conditions. For antenna mismatches likely
to be encountered in practice, the actual limit will approach the 18 Volt figure.
Routine transmitter tests should be performed at EIA Standard Test Voltages of (13.6 Vdc for loads of 6 to 16 amperes; 13.4
Vdc for loads of 16 to 36 amperes). Input voltages must not exceed the limits shown, even for transient peaks of short
duration.
Many commonly used bench power supplies cannot meet these requirements for load regulation and transient voltage
suppression. Bench supplies which employ "brute force" regulation and filtering (such as Lapp Model 73) may be usable
when operated in parallel with a 12 volt automotive storage battery.
(Cont.)
CAUTION
TEST PROCEDURES
These Test Procedures are designed to assist you in servicing a transmitter that is operating -- but not properly. Once a defect is
pin-pointed, refer to the Transmitter Troubleshooting Procedure. Before starting, be sure that the transmitter is tuned and aligned to
the proper operating frequency.
(Cont.)
TEST PROGRAMMING
In DELTA-S radios, in which the EEPROM is not custom programmed, the EEPROM may be programmed with the
personality similar to the ones shown in Table 1 below. See data on production tag with radio for exact data.
Table 1 - Programmed Test Frequencies
FREQUENCY
SPLIT
CHANNEL
NO.
TRANSMIT
FREQUENCY
RECEIVE
FREQUENCY
CHANNEL GUARD
ENC/DEC
CCT
450-470 MHz 1
2
3
4
5
6
7 461.025
467.025
461.025
455.025
450.000
470.000
461.000 461.050
462.050
461.050
460.050
460.025
469.750
460.750 71.9
023
---
---
---
71.9
---
---
---
30 SEC
---
---
---
---
470-494 MHz 1
2
3
4
5
6
7 483.8875
489.8875
483.8875
477.8875
470.000
494.000
485.000 483.050
484.050
483.050
482.050
470.050
493.750
484.750 71.9
023
---
---
---
71.9
---
---
---
30 SEC
---
---
---
---
494-512 MHz 1
2
3
4
5
6
7 503.000
509.000
503.000
497.000
494.000
512.000
503.000 502.975
503.975
502.975
501.975
501.975
511.750
502.750 71.9
023
---
---
---
71.9
---
---
---
30 SEC
---
---
---
---
403-430 MHz 1
2
3
4
5
6
7 413.025
419.025
413.025
407.025
403.000
430.000
414.000 413.050
414.050
413.050
412.050
403.050
429.750
413.750 71.9
023
---
---
---
71.0
---
---
---
30 SEC
---
---
---
---
LBI-31511 LBI-31511
7