[Amps] QSK-5 diode mod

[kingwood]

Greetings to all,

        I just received a stand alone Ameritron QSK-5 that I bought on eBay. 
The unit would not key the Harbach soft start mod that was installed in my 
HL-2200 amp. An ohm meter check showed that the proper ground signal was 
available on the "AMP RELAY"  connector.  The problem turned out to be a 
diode that installed, on some units, from the lower circuit board to the RCA 
phono connector.  The diode was good but not pass the minimal current on the 
Harbach Soft Start control line.

        The last QSK-5 that I had in my shop did not have this diode 
installed.  Another QSK-5 that I worked on, had this diode shorted out.   My 
solution was to short a brightly colored wire so that the next operator can 
easily spot it.  Bring this wire up to the top of the top board and leave 
this wire long enough so that it can be easily accessed and cut, it you fine 
a need to have the diode in the circuit.

        The stand alone QSK-5 very well.  I really do suggest using the 
internal contacts to control the cut-off bias of the amp.  All the necessary 
switching is already on the board.  All you need to do is add a DPDT, 
shorting socket on the back of the QSK-5 and your amp and connect the with a 
two wire cable with standard 1/8' tip, ring, and sleeve plugs.  Works great. 
Have fun.

73 de Lon, K5JV

1110 Golden Bear Ln.
Kingwood, TX 77339

281-358-4207
281-358-4234 FAX
281-795-1335 CELL