I have had one in and out of a 32V3 XMTR several times repairing flood damage. It's not that hard. The oscillator circuit is not that complicated. I don't know the same about the 75A4 PTO removal, but if that is not to bad, then just fined the open resistor or the shorted capacitor and replace it. Be sure to check the DC and filament lines going into it first. Mine was filled with mud and had a stuck slug, which I broke trying to free it up. But I got it working. Of course the calibration is way off because of the broken slug, but that is not going to happen in your case. Yours was not full of mud for 2 - 3 years.
John WA5BXO -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of John Lawson Sent: Sunday, December 25, 2005 3:47 PM To: [email protected] Subject: [AMRadio] R-388 PTO info needed Further to my Xmas Eve Scrooge Radio Post - I have discovered that no signals of any kind appear on the PTO output cable when isolated from the mixer tube, and injecting the correct frequency into that pin of the mixer (from my bench oscillator) restores the radio to operation. So, of course, the PTO has quit, and the tubes (AFAIK) are good - but next I'll replace them with a couple that test out at better than 70% Gm - somehow I think that's not going to be the Problem. If anyone within the sound of my keyboard has any experience actually repairing this series of PTO - it's a Collins 70E-15 ser. M1751 - I'm trying to guage whether I should spend the time to dredge it out and fix it - or (since the front panel needs to be refinished) I would be better served by just bundling it off to someone and letting an expert refurb the radio. I do plan to keep it, it's my Fave Reciever - for Ham and SWL - Also: if you have a quote to perform the above, lemme know ASAP - I'm 'motivated' as they say in Real Estate. Cheers and Best of the Season! John KB6SCO ______________________________________________________________ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:[email protected] AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb
