Re: Currawong
Posted: Sat Sep 02, 2017 4:37 am
Poco a poco accelerando ...
Have solved two problems. Lost interest a few years ago when nothing seemed to work when I turned the amp on. The dualcolored LED that indicated HV on/off was lost and the circuitry controlling the delayed switching of HV wasn't working; I had accidently switched the BC549 and BC559 transistors.
Yesterday I soldered the correct transistors in correct places and noticed the only purpose of the transistors is to change color of the LED. That left me with the problem of the non-functioning turn-on delay. Quickly ruled out an electrolytic that is slowly charged and hooked to an imput of a schmitt trigger. Leakiy as it was it was never charged enough. Now that part is working but only two of the four 6L6s are heated up. Heater wires faulty??
Have solved two problems. Lost interest a few years ago when nothing seemed to work when I turned the amp on. The dualcolored LED that indicated HV on/off was lost and the circuitry controlling the delayed switching of HV wasn't working; I had accidently switched the BC549 and BC559 transistors.
Yesterday I soldered the correct transistors in correct places and noticed the only purpose of the transistors is to change color of the LED. That left me with the problem of the non-functioning turn-on delay. Quickly ruled out an electrolytic that is slowly charged and hooked to an imput of a schmitt trigger. Leakiy as it was it was never charged enough. Now that part is working but only two of the four 6L6s are heated up. Heater wires faulty??