On Fri, 24 Mar 2006 14:53:26 -0800, "Ron D'Eau Claire" <[EMAIL PROTECTED]> wrote:
>Matt asked: > >The local oscillator on the XV222 will not generate a sufficient signal >level. The voltage measured at TP1 is 0.45VDC. > >When first tested, TP1 read 0VDC. Seeing posts about a balky oscillator >being sensitive to L4A, I adjusted the slug while watching at TP1. Sure >enough, as the slug was adjusted, TP1 rose from 0VDC to 4.5VDC and then >started back toward 0VDC as I continued to turn the slug into L4A. > >I backed out the slug until TP1 read its maximum of 0.45VDC and then >continued out until the voltage at TP1 returned to 0VDC. > >When oscillating, the frequency measures at 193.995, which is well within >the accuracy of my frequency counter. > >I checked all components and voltages at Q1 & Q2, everything was correct. > >I'm sure there are some clues buried in the above observations, but I'm >unable to sort them out. Does anyone have any clue as to how I get the >voltage at TP1 up over 1.0VDC? > >--------------------------- > >Is the local oscillator transistor mounted up off the board with a Teflon >spacer on one lead as shown in the assembly manual? > Hi Ron, Yes, Q1 is mounted 3/8" high with the teflon spacer. I was thinking that the crystal is OK because it oscillates at the correct frequency. How critical is the MPS 918? Could I substitute a 2N2222 in place of Q1 just to check out the operation of Q2 (BFR96)? Is that a sensible thing to do? _______________________________________________ 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
