DRAKE TR7 매뉴얼 - 페이지 3

{카테고리_이름} DRAKE TR7에 대한 매뉴얼을 온라인으로 검색하거나 PDF를 다운로드하세요. DRAKE TR7 3 페이지. Alignment procedures

FINAL RECEIVER ALIGNMENT

(Back cover shield (or test shield) installed, check and align steps 26 through 29 only as

necessary).

26) Tune radio to a non-calibrator frequency, like 7.309 MHz, on fast AGC, calibrator and PBT off.

27) Set generator to the same frequency, output for about S5 to S7 on the meter. On the 2nd

IF/Audio board, peak L1101, L1102, T1102. On the 2nd mixer board, peak L701, L703, C716. Adjust

generator to maintain S5 to S7 during alignment.

28) Set generator to 7 microvolts (-90 dBm), tune radio for best signal noting reading on AC

voltmeter across speaker. Turn generator down 20 dB (0.7 microvolts, -110 dBm). On the 2nd

IF/Audio board, adjust R1136 for only a 2 dB drop on the AC voltmeter from the 7 microvolt (-90

dBm) reference.

29) Adjust R1128 on the 2nd IF/Audio board for an S1 meter reading. Set generator for 50,000

microvolt (-13 dBm) signal. Adjust R1105 for a S9 + 60 meter reading. Switch back and forth from

-110 dBm to -13 dBm on the generator and adjust R1128 and R1105 til no more improvement can

be made. S9 on the meter will typically be -73 dBm to -77 dBm, but does vary with tracking.

Usually favor S1 and S9 readings for pot settings.

30) Check all bands for 10 dB S+N/N (normally will be 12 to 13 dB) for 0.5 microvolts (-113 dBm).

Usually can just check one band, because transmit on these bands was OK.

31) On lightning damaged units, or if a problem is reported, be sure to check RV7 functions.

Otherwise check is not normally necessary.