User's Manual

1 1 7 B 2 0 W at t V H F H igh Band Transla t or Upconve rt er/ Am plifie r Tray
Det aile d Align m ent Pr oce dur e
- Page 4 of 5 -
The out put of the Am plifier Board at J2 (+ 44 dBm Visual and + 34 dBm Aural) is fed t o the Low Pass
Filt er Board.
( A18- A1) LOW PASS FI LTER BOARD (1174-1102, 1174- 1103 OR 1174-1104)
The Low Pass Filter Board is adj ust ed at the fact ory and should not need to be adj ust ed in the
field. The second part of the Board is a 2nd Harm onic Trap t hat is also factory adj ust ed and
should not be adjust ed.
The out put of the Low Pass Filter Board at J2 is fed t o a Trap Filter Board.
( A18- A2 & A18- A3) TRAP FI LTER BOARDS (1174- 1105 OR 1174-1106)
The t wo Trap Filt er Boards are adj ust ed at t he fact ory and should not need to be adj ust ed in the
field. Each board cont ains two Notch Circuit s. The Cent er Frequency of first not ch, -4.5 MHz, is
adj ust ed by C8, and t he depth of t he Not ch is adj ust ed by C6. The Cent er Frequency of second
notch, + 9 MHz, is adj ust ed by C4, and t he depth of the Notch is adj ust ed by C2. Both boards are
adj ust ed t he sam e.
The out put of the Trap Filter Board at J2 is fed t o a High Band VHF Coupler Board.
( A23) HI GH BAND VHF COUPLER BOARD ( 1141- 1002)
Forward and Reflect ed power sam ples are t aken from t he VHF Coupler Board and the Reflect ed
Sam ple is fed direct ly t o t he Visual/ Aural Met ering Board ( A26) . The Forward sam ple is split by
( A24) and fed to t he Visual/ Aural Met ering Board ( A26) .
The Output of the VHF Coupler Board ( A23) is connect ed to t he RF Out put Jack ( J4) of t he Tray
( + 43 dBm Visual and + 33 dBm Aural) .
( A26) VI SUAL/ AURAL METERI NG BOARD (1161-1103)
1. While m onitoring the RF output of the Tray, adj ust R101 on the ALC/ AGC Board ( A10), S2 in
AGC Manual, for a reading of 20 Watt s Peak Sync Power.
2. Switch the Front Panel Met er AGC Detect or Volt age Position and adjust R28 for .3 Volt s.
3. Switch the Front Panel Met er to t he % Aural Output Power position and adjust C5 for
Maxim um Aural Out put.
4. Adj ust R11 for a reading of 100% Aural Out put on the Front Panel Meter.
5. Rem ove the Aural by rem oving Jack J15 locat ed on t he Clam p/ Modulator Board in the
Modulat or Tray or by rem oving t he Aural from t he RF I nput to the Receiver Tray. Switch
the Front Panel Met er t o the Visual Output Power position and adj ust R29, located on t he
Visual/ Aural Met ering Board, for a reading of 100% on the front panel m et er.
6. I nsert the Aural back into t he Syst em . Adj ust R39 for 100% Out put in the Visual Output
Power posit ion.
Rem ove the cable now on J4 and m ove t he cable from J1 to J4. Switch t he Met er Select or Swit ch
to t he % Reflect ed Power Posit ion and adj ust R47 for a reading of 100% . Switch t he cable from J4
back t o J1 and reconnect t he cable t o J4.