Ahmad, We have had the output stages blow a couple of times in our Kalmus amp (they do NOT like reflected power), and have replaced the output transistors ourselves. There is a procedure in the service section of the manual for adjustmests. In our case, the transistors were about $140 each. Good solder/desolder skills are necessary. As for calibration, all we do is to connect a 50 ohm load and run the power up, checking the gain and harmonic content with a directional coupler and spectrum analyzer. Bob.
Ahmad Fallah <emcesd2...@yahoo.com> wrote: Hello all, Would anyone in the group know of a shop that can repair and calibrate Kalmus amplifiers? We have sent our broadband amplifier out for repairs, but the response has been very slow. Thanks, Ahmad Fallah