"Bob Donnell" <[EMAIL PROTECTED]> made an utterance to the drakelist gang ---------------------------------------------------------------------- An "off the top of my head" thought would be to looking at coupling or capacitors, since things work better at higher frequencies. Mind you this is without taking time to download a schematic and research it. On the other hand, I work with broad bandwidth RF PA's in my day job, though we don't make any tube amps anymore.
73, Bob, KD7NM -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Mark Pilant Sent: Monday, January 21, 2008 1:27 PM To: [EMAIL PROTECTED] Subject: Re: [drakelist] TR-3 crystals needed (was:TR-3 9 MHz osc & alignment questions) Mark Pilant <[EMAIL PROTECTED]> made an utterance to the drakelist gang ---------------------------------------------------------------------- Well, I think it may have been a bad user on device :-) :-) At Rich's (KE1EV) suggestion I measured the oscillator voltage and frequency at V1a. In particular, on the common crystal connection with only R3 and C2 between where I measured and the plate (pin 1) where Rich measured. Here is what I got: 80m 0.0v 40m 5.2v 21.496 MHz 20m 0.0v 15m 4.1v 35.496 MHz 10(1)m 4.1v 42.495 MHz 10(2)m 4.0v 42.994 MHz 10(3)m 3.6v 43.592 MHz Since there are no crystals for 80m and 20m, the 0V reading is understandable. These reading were taken after adjusting L1, L2 and L5 for the maximum negative voltage at the test point. I could get the frequencies closer to the specs but the T.P. voltage was not at the max. So it would seem the band crystals are, in fact, OK. I'm still puzzled why the readings are so strange looking at V1b pin 3. I'm going to have to think about this one for a while. I'm getting there, and learning/remembering a bunch along the way :-) 73 - Mark N1VQW ---------------------------------------------------------------------- Submissions: [EMAIL PROTECTED] Unsubscribe: [EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost: [EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net ---------------------------------------------------------------------- ---------------------------------------------------------------------- Submissions: [EMAIL PROTECTED] Unsubscribe: [EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost: [EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net ----------------------------------------------------------------------
