[EMAIL PROTECTED] made an utterance to the drakelist gang ----------------------------------------------------------------------
Fumble-fingers made an important type in the message below. The message should read "I had precisely 21.5mhz on 40m", which is the correct frequency. -- Rich Carter -------------- Original message ---------------------- From: [EMAIL PROTECTED] > > [EMAIL PROTECTED] made an utterance to the drakelist gang > ---------------------------------------------------------------------- > I am in the process of restoring a TR-3. I've spent a great deal of time > trouble-shooting the premixer, but I'm stumped. I'm about ready to throw my > hands up and send it out for repair. I'm not too cheap to pay someone to > help > out with this, but I started restoring this rig to help become more familiar > with tube transceivers and analog circuits. I hate to give up. > > The radio works well on 20 and 80 meters. On 40 meters, the premixer > oscillator > runs at 16.3 mhz instead of 20.5mhz. I get no power out. On the 15 and 10 > meter bands, the crystals read low by about 100khz. Last night, I poked > around > with a scope a little more and tweeked the 20m crystal alignment inductor and > suddenly the premixer was working. I had precisely 20.5mhz on 40m and the > other > bands measured correctly too. I found two leads under V3 that looked like > they > may have been shorted, so I blamed my problems on that. > > Emboldened with success, I proceeded to run through the alignment procedure. > I > went through the injection coupler alignment and on to the receiving IF > alignment. Then everything went south again. Figuring that maybe I had a > thermal issue, I turned the rig off and let is sit overnight. My hope was > that > this morning I would find the premixer working again. No such luck. I > suspect > that there may be something wrong with the alignment I did. I've double-and > triple checked the steps in the procedure. I've poked around with an > insulated > tool to see if I could find a bad solder joint or cracked component. I've > cleaned the band switch several times. > > The alignment instructions were written for folks who lacked modern test > equipment. Maybe there's an easier and more precise way to align the > premixer. > If it isn't something I did, then there is something marginal or intermittent > in > the circuitry. > > I'll have to admit that my analog background is limited. I can use a scope > and > I'm comfortable with digital circuits. I have a good scope and know how to > use > it. I'd appreciate any pointers from the group. I know that Mark (N1VQW) is > wrestling with his premixer too, so any tips would probably get double-duty. > > Thanks in advance > Rich KE1EV > > > > -- > Rich Carter > > ---------------------------------------------------------------------- > 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 ----------------------------------------------------------------------
