Table of Contents
Advertisement
3 SERVICE
3.6.8
MODULE PERFORMANCE CHECK OF POWER UNIT
3.6.8.1 CHECK OF VOLTAGE REGULATORS
1.
Connect a voltmeter to the outputs of the voltage regulators and check the voltages according to
the following table:
U01: +15V +/-1V
U02: -15V +/-1V
U03: +15V +/-1V
U04: -15V +/-1V
U06: +5.3V +/-0.2V
U07: +3.5V +/-0.3V
3.6.8.2 CHECK OF RF AMPLIFIER AND FILTER
1.
Connect a 50 ohm resistor to the aerial socket J01-2. Two 100 ohm resistors in parallel soldered
on a coax cable connected to the aerial socket are sufficient.
2.
Connect an oscilloscope through a 10:1 probe to the 50 ohm resistor.
3.
Connect a signal generator to P03-8 with an output power of -9 dBm.
4.
Control of the lowpass filter response is carried out by changing the frequency of the signal
generator and controlling the reading on the scope. Max. permissible ripple is 2 dB in the frequency
range 1.6 MHz to 30 MHz.
5.
Tune the signal generator to 22 MHz and read on the scope the voltage to 3.5 Vpp +/- 0.5V
3.7 ADJUSTMENT PROCEDURE
This chapter contains the adjustment procedure for all adjustable components in the RE2100.
3.7.1
ADJUSTMENT PROCEDURE FOR FRONT END AND RECEIVER UNIT
This chapter contains the following sections:
3.7.1.1. Adjustment of 70 MHz IF-Filter (Front End and Receiver)
3.7.1.2. Adjustment of 70 MHz Transformer (Receiver)
3.7.1.3. Adjustment of SSB/AM Filter (Receiver)
3.7.1.4. Adjustment of 2nd IF-Gain (Receiver)
3.7.1.5. Adjustment of Signal Meter (Receiver)
3.7.1.6. Adjustment of Earpiece Level (Receiver)
3.7.1.1 ADJUSTMENT OF 70 MHz IF-FILTER (Front End and Receiver)
The 70 MHz IF-filter is adjusted by tuning the three trimming coils L35-2, L36-2, L37-2, and the two
transformers TR04-2, TR01-1.
The components L35-2, L36-2, L37-2 and TR04-2 are all located at the front end unit (module 2), while
TR01-1 is located at the receiver unit (module 1).
The adjustment is performed by using the two service programmes SP-04-0 and SP-04-1. These
programmes set-up the first local oscillator (LO1) as a test signal and therefore no external signal
generator is necessary.
RE2100
PAGE 3-47
Hide quick links:
Advertisement
Table of Contents
