Icom IC-201, Руководство пользователя

Страница: 8 / 21

DL7MAJ, Oct 20
th
2015
Page 8 (21)
FM-IF
Alignment of FM-Unit can only be done outside the transceiver.
Use pins to connect supply (9V), Gnd, signals and meters acc. to the picture.
IMPORTANT:
An external trimmer R1 (10kOhm) has also to be connected, otherwise Q1 wouldn´t
operate.
1) Connect counter to TP2 (high impedance); frequency should be 10,/-1kHz
Use analog scope, probe 10:1, with Y-output to connect the counter if available
2) Connect IF-Signal 10,700MHz, 1mV, unmodulated to pin 3 and 4(Gnd)
3) Connect DC-voltmeter to pin 10
4) Adjust L1 and L2 for max. negative AGC-voltage at pin 10; reduce amplitude of IF-
signalgenerator as far as possible to find the point of best sensitivity; try variation of
R1
5) FM-modulate IF-signal with sinus 1kHz and 5kHz deviation
6) Connect scope to pin 9, AF audio
7) Connect DC-voltmeter to pin 6, center meter
8) Adjust L3 and L4 for best demodulation (scope) and 0V at center meter
9) Reinstall FM-Unit into the transceiver
10) Mode “FM”, “RX”
11) Tune in signal 50Mikrovolt 145,000MHz: Set R1 (mainboard nearby the FM-Unit) for
S=9