Hi John, Since the last correspondence in this thread that you had received, I got one sent by W7QHO on 4/8/2004 at 1:18AM EDT, I sent one on 4/8/2004 at 2:52AM \EDT, and got one more from RJ Mattson sent 4/8/2004 at 9:13AM EDT, that I didn't answer yet. Then (of course) yours sent 4/9/2004 at 11:05PM EDT, and W7QHOs reply sent 4/10/2004 at 1:18AM EDT.
Hmm, I was looking at the cathode capacitor... but it is shunted by the cathode resistor (R18), which is 100 ohms. to ground. The 807 will act as a cathode follower driving audio onto C27 and R18, but I think the cathode will be within about a few volts of ground potential at audio frequencies, so my guess is that a 0.01uF going from the screen to the cathode of the 807 will act like maybe 0.008 or 0.009uF to actual ground, for audio. Slightly reduced, but still pretty much a 0.01uF. This 0.008uF (a guess) will face the 15K in parallel with the screen impedance, or maybe 5K combined (another guess). I think it is too large for high audio frequencies. But you should be able to do tests at low audio frequencies below about 400 Hz. Actualy, R18 ought to produce negative audio feedback, and reduce modulation distortion in the 807. I'll have to think about that. Bacon, WA3WDR ----- Original Message ----- From: <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]>; <[email protected]> Sent: Saturday, April 10, 2004 1:18 AM Subject: Re: [AMRadio] Plate modulating a 807 In a message dated 4/9/04 8:07:33 PM, [EMAIL PROTECTED] writes: > I have a feeling that I am only getting some of the reflected email. I > have not received back two dup ones that I sent and I can find no other > mention of the subject below. Is any one else experiencing this? > Yes! Dennis D. W7QHO Glendale, CA --- StripMime Report -- processed MIME parts --- multipart/alternative text/plain (text body -- kept) text/html The reason this message is shown is because the post was in HTML or had an attachment. Attachments are not allowed. To learn how to post in Plain-Text go to: http://www.expita.com/nomime.html --- _______________________________________________ AMRadio mailing list [email protected] http://mailman.qth.net/mailman/listinfo/amradio
