Hi Kihwal, Don't toss that PTO out...!
I know Garey expressed interest some time ago in acquiring a "bad" one, so that he might perform some "post mortem" work upon it for educational sake... As long as you have the PTO board in your hand, "jiggle" the different components between your thumb & forefinger, looking for suspect solder joints: I did that very thing with the PTO in my just-plain-Jane TR-4 here, & discovered that BOTH joints in a SM cap therein were bad. Yours may be the exact same thing---who knows? In any event, before swapping-out transistors, look at other parts, first! And don't forget Garey's (possible) interest in acquiring your ailing PTO... ~73~ de Eddy VE3CUI - VE3XZ **************************************************************************** **************************************************************************** ***** ----- Original Message ----- From: Kihwal Lee To: Drakelist Sent: Monday, May 09, 2011 10:29 AM Subject: [Drakelist] R-4A PTO The PTO in my R-4A failed a few days ago. I replaced it with a spare I had, but I still want to fix it as it has better linearity. In case the transistors are bad, what are the proper substitutes? It has a 2N3058 and a 2N706. Kihwal, K9SUL _______________________________________________ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist _______________________________________________ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
