Does anyone have the schematic for the vintage tube-based KROHN-HITE MODEL 440-A Oscillator that they could scan and send me, or point to a link (I haven't found one.) It's bigger than some boatanchors! Mind has just died - no oscillation (but it was working.) I have found a dead 6H6 tube (double-diode, heater open circuit - it may not be critical and I could replace it with a 6AL5 with a base adapter); also found a low emission 6AU5 (beam power tube) - it seems to be a B+ regulator but I still seem to have good B+. All 6SL7's test OK to "good"; I subbed the worst one but still no oscillation. All other tubes test OK to "good+". Now I'm stuck! I'm blind w/o a schematic on this one. Thanks for all replies. Cheers, Roger PS. email address shown is fake (anti-spam.) Kindly use analogdino at (ta-boy) rogers dot(ty as they) com(e), suitably decoded. Tks. PPS. Also posted on RAR+P and sci.electronic.repair as group readers differ but do overlap. I hope no-one is offended.
- posted
14 years ago