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21. Re: [Amps] Pi vs Pi-L (score: 1): Author: jkearman@att.net (Jim Kearman); Date: Wed, 01 Feb 2006 19:05:36 +0000; The ubiquitous t-network tuner with series capacitors and a shunt inductor (like the MFJs) is a high-pass filter, so it won't help a bit. The old Johnson Matchboxes with parallel-tuned inputs would p; /archives//html/Amps/2006-02/msg00013.html (8,135 bytes)
22. Re: [Amps] T networks and harmonics (score: 1): Author: jkearman@att.net (Jim Kearman); Date: Tue, 07 Feb 2006 00:04:51 +0000; Of course, this is beyond the scope of my original post about the need for pi-L output tanks to meet current FCC requirements, but thanks for the backup. The Regs require spurious emissions be below; /archives//html/Amps/2006-02/msg00142.html (8,942 bytes)
23. [Amps] Choke-input with voltage doubler? (score: 1): Author: jkearman@att.net (Jim Kearman); Date: Thu, 09 Feb 2006 17:07:13 +0000; My friend obtained a 1000-VCT brute of a transformer, weighs 25 lb. Old Chicago Transformer, potted, looks mil-surplus. I assume it was made for a choke-input filter. He wants to use the full seconda; /archives//html/Amps/2006-02/msg00207.html (7,090 bytes)
24. Re: [Amps] Choke-input with voltage doubler? (score: 1): Author: jkearman@att.net (Jim Kearman); Date: Thu, 09 Feb 2006 18:54:48 +0000; What about using a small series-R from each half of the doubler? I think regulation is less of a factor here because most of the current will be continuous. 73, Jim, KR1S http://kr1s.kearman.com/ __; /archives//html/Amps/2006-02/msg00210.html (7,316 bytes)
25. Re: [Amps] Here's something you don't see every day (score: 1): Author: jkearman@att.net (Jim Kearman); Date: Tue, 14 Feb 2006 18:25:26 +0000; I want to be his power company! But I sure don't want to be his neighbor. 73, Jim, KR1S http://kr1s.kearman.com/ _______________________________________________ Amps mailing list Amps@contesting.com; /archives//html/Amps/2006-02/msg00260.html (8,001 bytes)
26. Re: [Amps] Tokyo HP (score: 1): Author: jkearman@att.net (Jim Kearman); Date: Fri, 17 Feb 2006 18:43:25 +0000; Let's put this in perspective. We can probably assume THP amps meet current FCC requirements for spurs, and it is legal for U.S. hams to run up to 1500 out, except on 30 meters. Not only do bootleg C; /archives//html/Amps/2006-02/msg00315.html (7,491 bytes)
27. Re: [Amps] Tokyo HP (score: 1): Author: jkearman@att.net (Jim Kearman); Date: Fri, 17 Feb 2006 19:37:14 +0000; As I said, Bill, let's put this in perspective. There is a huge gap between using amps on 11 meters and buying a THP amp direct, and using it at a licensed Amateur station. Comparing them in the sam; /archives//html/Amps/2006-02/msg00319.html (7,894 bytes)
28. [Amps] Stuck Powerstat (score: 1): Author: jkearman@att.net (Jim Kearman); Date: Sun, 19 Feb 2006 20:51:21 +0000; I got a 10-amp 240-V Superior Powerstat for a good price at a hamfest, but the wheel is jammed and I can't figure out why. I removed the brush and AFAIK there's nothing to prevent the wheel from turn; /archives//html/Amps/2006-02/msg00356.html (6,550 bytes)
29. Re: [Amps] 87A vs. IC-PW1 (score: 1): Author: jkearman@att.net (Jim Kearman); Date: Wed, 22 Feb 2006 18:53:27 +0000; If a DX station is listening on or close to his frequency and has a pileup, which is the usual case in a contest, you have to be able to hear when the DX goes back to someone -- you, for example. If; /archives//html/Amps/2006-02/msg00385.html (7,751 bytes)
30. Re: [Amps] 87A vs. IC-PW1 (score: 1): Author: jkearman@att.net (Jim Kearman); Date: Wed, 22 Feb 2006 19:04:28 +0000; OTOH, if you've never used QSK, how do you know it wouldn't help? I've never used a parachute, either, but in certain circumstances I hear they're pretty handy. :) 73, Jim, KR1S http://kr1s.kearman.c; /archives//html/Amps/2006-02/msg00387.html (8,372 bytes)
31. Re: [Amps] 87A vs. IC-PW1 (score: 1): Author: jkearman@att.net (Jim Kearman); Date: Thu, 23 Feb 2006 00:38:18 +0000; You said it Gary, I didn't say it. But do we all need a refresher course in Logic? Someone else opined that those who have "worked them all" must axiomatically not be lids. Now this attempt to bring; /archives//html/Amps/2006-02/msg00409.html (8,337 bytes)
32. Re: [Amps] QSK (score: 1): Author: jkearman@att.net (Jim Kearman); Date: Thu, 23 Feb 2006 00:45:11 +0000; I think that once upon a time, people did care. Those B&W electronic switches couldn't all have been sold to traffic handlers. I built a similar circuit into my DX-100, and later my Valiant. (It used; /archives//html/Amps/2006-02/msg00410.html (7,169 bytes)
33. Re: [Amps] QSK (score: 1): Author: jkearman@att.net (Jim Kearman); Date: Thu, 23 Feb 2006 01:17:54 +0000; No no no. I did NOT say that. Someone else did. I only quoted it in my reply. 73, Jim, KR1S http://kr1s.kearman.com/ _______________________________________________ Amps mailing list Amps@contesting.; /archives//html/Amps/2006-02/msg00413.html (7,424 bytes)
34. Re: [Amps] QSK (score: 1): Author: jkearman@att.net (Jim Kearman); Date: Thu, 23 Feb 2006 16:27:19 +0000; Some discussion on PIN QSK switches and the life expectancy of vacuum relays that track dots and dashes would be useful and on-topic. How are people who homebrew high-power HF amps handling this? In; /archives//html/Amps/2006-02/msg00439.html (8,233 bytes)
35. Re: [Amps] QSK (score: 1): Author: jkearman@att.net (Jim Kearman); Date: Thu, 23 Feb 2006 17:29:00 +0000; Interesting how the scope of this discussion keeps expanding exponentially. From memory keyers, we have now boldly leapt into full station automation in the blink of a dit. The website url in my sig; /archives//html/Amps/2006-02/msg00447.html (9,099 bytes)
36. Re: [Amps] QSK (score: 1): Author: jkearman@att.net (Jim Kearman); Date: Thu, 23 Feb 2006 19:49:04 +0000; Hams who have done much CW DXing know that hitting the button at the right instant can make the difference. I don't equate current levels of station automation with "effortless" by any stretch. I gue; /archives//html/Amps/2006-02/msg00456.html (9,049 bytes)
37. Re: [Amps] QSK (score: 1): Author: jkearman@att.net (Jim Kearman); Date: Thu, 23 Feb 2006 21:37:03 +0000; Likewise, Joe, because I didn't criticize your favorite modes of operation, or imply that any given use of technology is unsat. You did. I _suggested_ people use a memory keyer to reduce mistakes and; /archives//html/Amps/2006-02/msg00463.html (8,984 bytes)
38. Re: [Amps] ALC (score: 1): Author: jkearman@att.net (Jim Kearman); Date: Fri, 24 Feb 2006 05:40:03 +0000; The problem is, the processing would ideally be done in the transmitter, not the amplifier. There's no reason it has to, but transceivers are already so full of digital stuff, a little more wouldn't; /archives//html/Amps/2006-02/msg00484.html (6,971 bytes)
39. Re: [Amps] Not in this lifetime (score: 1): Author: jkearman@att.net (Jim Kearman); Date: Sun, 26 Feb 2006 13:42:31 +0000; Some email clients and mail servers can be set to challenge email from unknown senders, requiring some sort of validation before letting the email go through. Usually you only have to reply to the me; /archives//html/Amps/2006-02/msg00583.html (7,643 bytes)
40. [Amps] Speaking of PIN T/R switches (score: 1): Author: jkearman@att.net (Jim Kearman); Date: Mon, 06 Mar 2006 21:10:12 +0000; I have it in mind to build a 400-W MOSFET amp for 80-40 and would be interested in experimenting with PIN-diode T/R switching. I'm aware of the problems with high VSWR but I can deal with them. But I; /archives//html/Amps/2006-03/msg00130.html (6,836 bytes)

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