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241. [AMPS] dummy loads (score: 1): Author: w8jitom@postoffice.worldnet.att.net (w8jitom@postoffice.worldnet.att.net); Date: Mon, 16 Jun 1997 11:41:30 +0000; I'm "trained" to think that way. I should have read the e-mail header. That might be what he was thinking. But the real problem is ALWAYS heat over time, not the CCS free air rating. The connector o; /archives//html/Amps/1997-06/msg00227.html (10,259 bytes)
242. [AMPS] two tone test (score: 1): Author: w8jitom@postoffice.worldnet.att.net (w8jitom@postoffice.worldnet.att.net); Date: Mon, 16 Jun 1997 11:41:30 +0000; I'm sorry I lost the mail about the two tone test. Here is why it is done in amateur linear PA's. SSB (and some other) forms of modulation contain multiple frequencies at the same time. If you rememb; /archives//html/Amps/1997-06/msg00228.html (9,675 bytes)
243. [AMPS] splatter (score: 1): Author: w8jitom@postoffice.worldnet.att.net (w8jitom@postoffice.worldnet.att.net); Date: Mon, 16 Jun 1997 11:41:31 +0000; To: <amps@contesting.com> No Peter, that still is not correct. Minimum grid voltage is just that, minimum grid voltage. No where does it say it has to be zero volts, and no where does it say the pla; /archives//html/Amps/1997-06/msg00229.html (13,100 bytes)
244. [AMPS] Re: (score: 1): Author: w8jitom@postoffice.worldnet.att.net (w8jitom@postoffice.worldnet.att.net); Date: Mon, 16 Jun 1997 22:21:22 +0000; Peter said.... Rich said... . Rich, Peter is correct. If you owned proper test equipment, experimented, and made measurements of IMD, you would understand neither Peter nor his spectrum analyzer is; /archives//html/Amps/1997-06/msg00236.html (7,955 bytes)
245. [AMPS] two tone test (score: 1): Author: w8jitom@postoffice.worldnet.att.net (w8jitom@postoffice.worldnet.att.net); Date: Mon, 16 Jun 1997 22:21:22 +0000; Hi Joe, I don't think much of that method, because the exciter always has IMD distortion and less than perfect sideband and carrier suppression. Most tube PA's will go far beyond what a modern solid; /archives//html/Amps/1997-06/msg00237.html (8,644 bytes)
246. [AMPS] AB1/2 (score: 1): Author: w8jitom@postoffice.worldnet.att.net (w8jitom@postoffice.worldnet.att.net); Date: Mon, 16 Jun 1997 22:21:22 +0000; That's right Peter. I'm sorry I didn't explain that better. A drawing would have helped, hi. My point was there is absolutely NO requirement the grid go positive with respect to the cathode in ANY l; /archives//html/Amps/1997-06/msg00238.html (9,244 bytes)
247. [AMPS] splatter (score: 1): Author: w8jitom@postoffice.worldnet.att.net (w8jitom@postoffice.worldnet.att.net); Date: Mon, 16 Jun 1997 22:21:22 +0000; That's right Bill, perhaps it would be clearer to say the least negative? Some tubes can have the grids driven positive without measurable grid current. I tried to explain that difference earlier. T; /archives//html/Amps/1997-06/msg00239.html (10,419 bytes)
248. [AMPS] Re: Two tone (score: 1): Author: w8jitom@postoffice.worldnet.att.net (w8jitom@postoffice.worldnet.att.net); Date: Tue, 17 Jun 1997 08:57:06 +0000; To: <amps@contesting.com> That's true, evaluating the exciter you do have to use two audio tones, but mix them cleanly before the rig dirties them up. Most of our solid state amateur rigs I've teste; /archives//html/Amps/1997-06/msg00246.html (10,579 bytes)
249. [AMPS] Re: Two tone (score: 1): Author: w8jitom@postoffice.worldnet.att.net (w8jitom@postoffice.worldnet.att.net); Date: Tue, 17 Jun 1997 11:37:51 +0000; To: <amps@contesting.com> Excellent. I follow the idea now. You notch a narrow frequency area of the output of the white noise generator, and see how much the PA fills in that area. By the way, I ho; /archives//html/Amps/1997-06/msg00250.html (8,884 bytes)
250. [AMPS] Amp faliure (score: 1): Author: w8jitom@postoffice.worldnet.att.net (w8jitom@postoffice.worldnet.att.net); Date: Tue, 17 Jun 1997 11:37:50 +0000; Current would get pretty high before the cathode cools off. It could easily wipe out the tube or power supplies. Bias should be the first thing on, and last thing off. That's why the bias supply is; /archives//html/Amps/1997-06/msg00251.html (7,487 bytes)
251. [AMPS] failure (score: 1): Author: w8jitom@postoffice.worldnet.att.net (w8jitom@postoffice.worldnet.att.net); Date: Wed, 18 Jun 1997 11:09:36 +0000; To: <amps@contesting.com> Hi Pete, Don't bet more than a beer on that! The main heating of tube elements (other than the filament) is by kinetic energy from electrons. Since the electrons are leavin; /archives//html/Amps/1997-06/msg00261.html (9,443 bytes)
252. [AMPS] failure (score: 1): Author: w8jitom@postoffice.worldnet.att.net (w8jitom@postoffice.worldnet.att.net); Date: Wed, 18 Jun 1997 23:18:57 +0000; To: <amps@contesting.com> Hi Peter, Everything I've read indicates no damage occurs to a thoriated tungsten emitter from attempts to run excessive current. The emission simply stops increasing. For; /archives//html/Amps/1997-06/msg00272.html (8,827 bytes)
253. [AMPS] SB-220 (score: 1): Author: w8jitom@postoffice.worldnet.att.net (w8jitom@postoffice.worldnet.att.net); Date: Wed, 18 Jun 1997 23:18:57 +0000; To: <amps@contesting.com> Hi Phil, As I understand what you are saying, you seem to be indicating turning the filament off and on does not decrease tube life. If so, I disagree with that. A very com; /archives//html/Amps/1997-06/msg00273.html (9,249 bytes)
254. [AMPS] Cold beer (score: 1): Author: w8jitom@postoffice.worldnet.att.net (w8jitom@postoffice.worldnet.att.net); Date: Thu, 19 Jun 1997 10:24:15 +0000; To: <amps@contesting.com> Hi Mike, As the electrons leave the cathode, they REMOVE thermal energy from the cathode. The amount of energy removed is very small, but it is removed. Electrothermal devi; /archives//html/Amps/1997-06/msg00282.html (10,294 bytes)
255. [AMPS] SB-220 (score: 1): Author: w8jitom@postoffice.worldnet.att.net (w8jitom@postoffice.worldnet.att.net); Date: Thu, 19 Jun 1997 10:59:59 +0000; To: <amps@contesting.com> I see we are indeed on the same wavelength. I didn't want anyone to think shutting the PA filaments off and on more than necessary was harmless, just because the inrush was; /archives//html/Amps/1997-06/msg00284.html (9,523 bytes)
256. [AMPS] SB-220 (score: 1): Author: w8jitom@postoffice.worldnet.att.net (w8jitom@postoffice.worldnet.att.net); Date: Thu, 19 Jun 1997 14:41:18 +0000; To: <amps@contesting.com> The 3CX1200 series uses the same filament structure as the 3-1000Z, 4-1000A, and similar tubes Are you saying the type of envelope affects the filament life? 73, Tom W8JI -; /archives//html/Amps/1997-06/msg00287.html (9,105 bytes)
257. [AMPS] Re: flux leakage (not) (score: 1): Author: w8jitom@postoffice.worldnet.att.net (w8jitom@postoffice.worldnet.att.net); Date: Thu, 19 Jun 1997 14:41:18 +0000; To: <amps@contesting.com> Hi Peter, It is the transformer's ESR, not leakage reactance, that limits inrush current. The ESR, as you seem to know, is mainly a combination of primary and secondary cop; /archives//html/Amps/1997-06/msg00288.html (7,659 bytes)
258. [AMPS] Re: 220 core saturation (NOT) (score: 1): Author: w8jitom@postoffice.worldnet.att.net (w8jitom@postoffice.worldnet.att.net); Date: Fri, 20 Jun 1997 09:00:30 +0000; To: <amps@contesting.com> Hi Peter, That's correct Pete, it is not a high leakage transformer. It has a very compact winding on a short magnetic path core, and hence has very little flux leakage. By; /archives//html/Amps/1997-06/msg00304.html (10,938 bytes)
259. [AMPS] Question about neutralizing (score: 1): Author: w8jitom@postoffice.worldnet.att.net (w8jitom@postoffice.worldnet.att.net); Date: Fri, 20 Jun 1997 09:00:29 +0000; To: <amps@contesting.com> Hi Bill, If system reactances were zero, then what you say would be true. The phase shift is not 180 degrees at RF, the feedback capacitance puts phase lead in the system (; /archives//html/Amps/1997-06/msg00305.html (9,371 bytes)
260. [AMPS] Delrin Spreaders (score: 1): Author: w8jitom@postoffice.worldnet.att.net (w8jitom@postoffice.worldnet.att.net); Date: Fri, 20 Jun 1997 10:41:27 +0000; To: <amps@contesting.com> Hi Larry, The whole "dissipation factor thing" seems to be an out-ofcontext explanation. We should really look to see how the change affects the system. (A similar thing oc; /archives//html/Amps/1997-06/msg00310.html (9,666 bytes)

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