I'm not quite sure what you mean about the "crystal cans" not being shorted to ground. They are supposed to be grounded.
73, Doug W6JD ----- Original Message ----- From: "Ward Willats" <[EMAIL PROTECTED]> To: <elecraft@mailman.qth.net> Sent: Saturday, October 02, 2004 3:30 PM Subject: [Elecraft] OPT1 low volume > I'm still trying to figure out why signals drop when I switch in OPT1 > on my newly-built SSB board for my K2/100. The static goes way down, > but do do the voices! > > Last weekend I discovered rfc2 shorting out to they can of crystal > X7. When I rewound it that helped some. > > Today I rewound T2 and that didn't make any difference at all. > > I've been around once with Gary, and I think all the obvious things > are right. The crystal cans aren't shorted to ground, the caps are > the right values and aren't shorted by DC either, the diodes are in > the right way and the voltage checks on the switching network are > fine. > > Gary says there should be a "small but progressive" signal loss > through the SSB filter. To check this, I tuned to the birdie at the > bottom of 40 meters, and dragged out the scope. > > I set in on a 2mv scale with a 1ms sweep (slow) and used the > measuring cursors to take an average amplitude. I did AC coupling > with a 1X probe (so may have been loading things down some). Then I > shoved a 3 inch leftover component lead into the probe clip so I > could poke around in the small places. > > Here are the numbers, from input to output: > > P2 -> T1(2) -> T2(4) -> X1 == ~ 1.75mv > > before X2 1.28mv > before X3 1.28mv > before X4 1.28mv > before X5 1.28mv > before X6 1.20mv > before X7 1.20mv > > T2(3) 1.20mv > T2(1) --> all the way out to P3 ~1.68mv > > I can go around again with Gary -- but before the weekend goes and > before I tear too much working stuff up, thought I'd throw it out to > you guys to see if there is anything obviously wrong with these > numbers or the way I acquired them. > > Thanks, > > -- Ward > _______________________________________________ > Elecraft mailing list > Post to: Elecraft@mailman.qth.net > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
