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301. [AMPS] Conjugate Matching In Class B and C Amplifiers (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Wed, 16 May 2001 09:54:42 -0400; Conjugate matching deals only with the condition for maximum available power transfer. Input matching only affects output matching when the amplifier has feedback of some type. Not in any of my book; /archives//html/Amps/2001-05/msg00305.html (14,108 bytes)
302. [AMPS] Conjugate Matching and Efficiency (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Fri, 25 May 2001 22:37:42 -0400; I haven't been following this....but.... The only possible heat source in a reactance is due to loss resistance. In a good quality capacitor, loss is almost zero. Small mica caps can be as low as 500; /archives//html/Amps/2001-05/msg00436.html (11,153 bytes)
303. [AMPS] Conjugate Matching and Efficiency (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Sat, 26 May 2001 14:14:27 -0400; That certainly makes sense. The source does not have to "produce" the RF power when the load isn't matched. The sources we use are energy converters that convert a dc source to RF with a time-varyin; /archives//html/Amps/2001-05/msg00450.html (10,208 bytes)
304. [AMPS] Conjugate Matching and Efficiency (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Mon, 28 May 2001 18:16:52 -0400; These theorems can never be used to explain what happens inside a source. That fact is very clear. They can be used to describe the way a source "looks" to a load. That is also well documented and e; /archives//html/Amps/2001-05/msg00483.html (12,270 bytes)
305. [AMPS] bandplan (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Tue, 29 May 2001 10:28:06 -0400; Hi, I'm sending you this about the 160m bandplan. Please pass this along. I think the committee is making a serious mistake. We need to write them now before they ruin things. Hi Rick, I was speaking; /archives//html/Amps/2001-05/msg00491.html (8,300 bytes)
306. [AMPS] Conjugate Matching and Efficiency (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Tue, 29 May 2001 11:35:08 -0400; It isn't if I say we can or can't do it that is important. What is important is the MODEL says we can't use the model that way! Say we have a transmission line coming out of a wall and we don't know; /archives//html/Amps/2001-05/msg00494.html (10,602 bytes)
307. [AMPS] Conjugate Matching and Efficiency (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Wed, 30 May 2001 11:23:57 -0400; This stuff will go on forever! The ARRL was very surprised when there were no favorable responses from these people. As a matter of fact, the staff at QST went out of its way to find someone they tr; /archives//html/Amps/2001-05/msg00526.html (10,722 bytes)
308. [AMPS] Toggle for Amp Supply AL-1000 (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Mon, 2 Apr 2001 10:14:32 -0400; Phil, It amazes me what people sometimes expect. I'm sure Ameritron knows nothing about that switch. Why should they know any more about Amp Supply parts than any other company would know? Why not c; /archives//html/Amps/2001-04/msg00011.html (7,812 bytes)
309. [AMPS] Toggle for Amp Supply AL-1000 (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Mon, 2 Apr 2001 23:00:08 -0400; The switch you want was an off-the-rack switch at Radio Shack. I saw them hanging in Radio Shack in 1990 or so. Ameritron NEVER owned Amp Supply. It is very unlikely a company never owning another c; /archives//html/Amps/2001-04/msg00014.html (8,084 bytes)
310. [AMPS] 4-1000A Project (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Tue, 3 Apr 2001 15:07:04 -0400; I avoid variacs because they reduce dynamic regulation of the supply. I've never found that! The 4-1000A was an impressive tube in 1955 or 1960, but it is anemic by today's standards. Even with anod; /archives//html/Amps/2001-04/msg00021.html (9,763 bytes)
311. [AMPS] 4-1000A Project (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Tue, 3 Apr 2001 15:24:41 -0400; Choke input filters generally have close to unity power factor, so that make life with a variac somewhat better. Was is the NL/FL voltage regulation? Regulation is the issue, not temperature. With a; /archives//html/Amps/2001-04/msg00023.html (9,475 bytes)
312. [AMPS] 4-1000A Project (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Tue, 3 Apr 2001 15:24:41 -0400; Hi Bill, I agree with that..... .....but that seems overly optimistic. I could NOT get 1500 watts out with any cathode driven 4-1000A with 100 watts of drive unless HV was nearly 6000 volts. A 3CX120; /archives//html/Amps/2001-04/msg00024.html (9,636 bytes)
313. [AMPS] 4-1000A Project (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Tue, 3 Apr 2001 20:33:51 -0400; Now that seems more like it. My recollection of the 4-1000A's are from older QRP rigs, that made lot's of noise and lit up the room. As I recall, the driving impedance was way up there in that lower; /archives//html/Amps/2001-04/msg00035.html (9,233 bytes)
314. [AMPS] Floating Ground (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Wed, 4 Apr 2001 13:02:15 -0400; The floating ground is so GRID current can be measured independently of ANODE current, without having the meters in the positive anode line or between the grid and chassis. You should ALWAYS have mo; /archives//html/Amps/2001-04/msg00068.html (7,541 bytes)
315. [AMPS] 4-1000A Project (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Wed, 4 Apr 2001 13:02:14 -0400; I'm afraid it does make sense Jon. The is no "design impedance" for a switched inductor sitting on your table, because the design impedance varies with loaded Q and frequency. You could say the "des; /archives//html/Amps/2001-04/msg00069.html (10,339 bytes)
316. [AMPS] 4-1000A Project (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Wed, 4 Apr 2001 17:21:46 -0400; Hi Phil, You can not select enough voltage breakdown for a worse case scenario in a tank circuit, unless you include a shutoff or spark gap or limit unloaded Q. All you can do is pick something reas; /archives//html/Amps/2001-04/msg00077.html (9,388 bytes)
317. [AMPS] 4-1000A Project (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Wed, 4 Apr 2001 21:14:21 -0400; A Q of 12 is NOT some kind of magic number. It is a suggestion, and efficiency varies only a small amount if the Q is 20 or 6 if it is done with good tank components. 12 is a number that makes peopl; /archives//html/Amps/2001-04/msg00082.html (9,857 bytes)
318. [AMPS] Re: close calls (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Thu, 5 Apr 2001 09:42:19 -0400; I was almost killed by using the resonant choke circuit in Bill Orr's handbook. I used the formula he suggested and build a resonant choke filter, not knowing you really must have resonance above th; /archives//html/Amps/2001-04/msg00104.html (11,122 bytes)
319. [AMPS] 4-1000A Project (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Thu, 5 Apr 2001 09:42:19 -0400; Someone else made a post explaining this one way, but there are several ways to look at it. Consider the pi two back-to-back L's. If the center impedance is not lower than the load and source impeda; /archives//html/Amps/2001-04/msg00105.html (10,271 bytes)
320. [AMPS] variacs (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Thu, 5 Apr 2001 09:56:42 -0400; It has been pointed out several times that with a choke input the loss of regulation from using a variac is generally minimal. In many cases it is acceptable. Capacitor input supplies are another st; /archives//html/Amps/2001-04/msg00106.html (7,391 bytes)

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