Mail Archive Search: <+from:jtml@lanl.gov>

Results:

References: [ +from:jtml@lanl.gov: 562 ]

Total 562 documents matching your query.

381. [Amps] cathode drive (score: 1): Author: "John T. M. Lyles" <jtml@lanl.gov>; Date: Wed, 28 Jan 2004 12:10:40 -0700; Cathode driven tetrodes is often used for VHF/UHF applications, as the input impedance of the grid is difficult to match with low enough Q. As Rich said, the driving Z is easier to match driving into; /archives//html/Amps/2004-01/msg00326.html (8,901 bytes)
382. [Amps] cooling big tube seals (score: 1): Author: "John T. M. Lyles" <jtml@lanl.gov>; Date: Sun, 15 Feb 2004 10:43:44 -0600; There are good reasons against using suction in an amplifier for cooling. Any small holes, seams in the chassis will aid the egress (or is is ingress?) of dust and dirt. By pressurizing the chassis f; /archives//html/Amps/2004-02/msg00122.html (9,892 bytes)
383. [Amps] Heathkit SB220 HV transformer p/n (score: 1): Author: "John T. M. Lyles" <jtml@lanl.gov>; Date: Sat, 21 Feb 2004 08:49:50 -0600; I looked at my SB220 parts list. The HV transformer is p/n 54-237 and the filament/bias is 54-238. The multimeter is p/n 407-146. Sounds like Dennis has the correct meters but the transformer is not; /archives//html/Amps/2004-02/msg00196.html (7,252 bytes)
384. [Amps] grounded anode RF (score: 1): Author: "John T. M. Lyles" <jtml@lanl.gov>; Date: Fri, 27 Feb 2004 12:56:13 -0700; I own several commercial RF systems that are configured this way, to a degree. 1) WT Larose Thermall dielectric preheater, that i test plastics, hoses, and insulators in before designing them into hi; /archives//html/Amps/2004-02/msg00294.html (9,128 bytes)
385. [Amps] failures of tubes with handles (score: 1): Author: "John T. M. Lyles" <jtml@lanl.gov>; Date: Sat, 6 Mar 2004 21:45:03 -0600; I just finished a grueling week working with a team of 6, rebuilding two large amplifiers which were horribly damaged due to a bizarre failure mode in the controls and operator mistake. Destroyed wer; /archives//html/Amps/2004-03/msg00068.html (8,547 bytes)
386. [Amps] microwave oven reused parts (score: 1): Author: "John T. M. Lyles" <jtml@lanl.gov>; Date: Mon, 22 Mar 2004 09:32:54 -0700; The cathode (-) power supply may have a large steel canned capacitor around 1 uF. It is rated for high AC voltage in doubler service, and is usually polypropylene dielectric. If it is rated for few k; /archives//html/Amps/2004-03/msg00246.html (7,392 bytes)
387. [Amps] insulation (score: 1): Author: "John T. M. Lyles" <jtml@lanl.gov>; Date: Wed, 24 Mar 2004 10:37:30 -0700; G10 will melt down into an awful stinkin' and burnin' mess when heated in high Rf fields. I rarely use it anymore, except for PW applications. It is certainly a big step above Delrin acetals or nylon; /archives//html/Amps/2004-03/msg00260.html (8,529 bytes)
388. [Amps] Re: insulation (score: 1): Author: "John T. M. Lyles" <jtml@lanl.gov>; Date: Wed, 24 Mar 2004 11:09:00 -0700; Yes it is given that I work with bigger handled tubes mostly. I also have to consider a second parameter when selecting insulators for some of our RF amps, and thats gamma, beta and sometimes neutron; /archives//html/Amps/2004-03/msg00262.html (7,254 bytes)
389. [Amps] more on RF insulation (score: 1): Author: "John T. M. Lyles" <jtml@lanl.gov>; Date: Fri, 26 Mar 2004 10:52:25 -0700; Comments have mentioned Delrin*, nylon and Teflon*: Delrin* acetal resin is a crystalline thermoplastic made from polymerization of formaldehyde. In the handbook by Dupont, it has lots of outstanding; /archives//html/Amps/2004-03/msg00296.html (9,413 bytes)
390. [Amps] Vishay RF capacitors (score: 1): Author: "John T. M. Lyles" <jtml@lanl.gov>; Date: Fri, 26 Mar 2004 10:55:53 -0700; Looking at the catalog that was mentioned, from Vishay, it seems that they have taken over the Draloric RF capacitor line, from Germany. Another little company gets eaten by a big conglomerate. John; /archives//html/Amps/2004-03/msg00297.html (6,674 bytes)
391. [Amps] tuned choke (score: 1): Author: "John T. M. Lyles" <jtml@lanl.gov>; Date: Sun, 28 Mar 2004 19:29:10 -0700; Skipp Tuned to resonance with no load, when you need it the most. When current load is increased, the tuned choke's equiv impedance falls to that of inductive reactance alone as the L changes (drops); /archives//html/Amps/2004-03/msg00335.html (7,751 bytes)
392. [Amps] tx tube tester (score: 1): Author: "John T. M. Lyles" <jtml@lanl.gov>; Date: Sun, 11 Apr 2004 07:23:06 -0600; Bill Fantastic! I always wondered when there would be a plug and play tube tester for larger power tubes with pins. Who makes the 701A? Hadn't heard of it. John K5PRO I need a data sheet on a 701A te; /archives//html/Amps/2004-04/msg00075.html (7,500 bytes)
393. [Amps] separate HV transformer location (score: 1): Author: "John T. M. Lyles" <jtml@lanl.gov>; Date: Wed, 21 Apr 2004 12:12:16 -0600; Jim Isbell, Seems like a good idea to me. I haven't thought out all the odds and ends, but we do this at work, we have 30 kV DC (@30 Amps) transformers outside, with FW rectifiers in the same oil tan; /archives//html/Amps/2004-04/msg00134.html (8,038 bytes)
394. [Amps] new amplifier results (score: 1): Author: "John T. M. Lyles" <jtml@lanl.gov>; Date: Fri, 23 Apr 2004 10:19:30 -0600; Is Heath Robinson the UK's version of Rube Goldberg here in the states? Worked, but always seemed a bit Heath Robinson to me...... 73 Peter G3RZP I am testing a new RF PA, this one using the THALES T; /archives//html/Amps/2004-04/msg00170.html (7,598 bytes)
395. [Amps] switchmode filament PS (score: 1): Author: "John T. M. Lyles" <jtml@lanl.gov>; Date: Sun, 25 Apr 2004 23:03:00 -0600; The TH781 tetrode PA that I am testing has one side of the filament grounded, to one of the transmission lines in the input resonator. Because of this, while I use 60 Hz transformer I get ripple on t; /archives//html/Amps/2004-04/msg00209.html (7,315 bytes)
396. [Amps] Re: Amps Digest, Vol 17, Issue 26 (score: 1): Author: "John T. M. Lyles" <jtml@lanl.gov>; Date: Thu, 20 May 2004 12:15:57 -0600; Will refers to Eric Lowdons book, published by Sams. Another book on transformer design is by the late Reuben Lee, one of Westinghouse's high voltage experts, dated 1947. "Electronic Transformers and; /archives//html/Amps/2004-05/msg00174.html (7,995 bytes)
397. [Amps] 8877 on 6 (score: 1): Author: "John T. M. Lyles" <jtml@lanl.gov>; Date: Mon, 24 May 2004 11:11:45 -0600; Gary The Harris socket arrangement is definitely for lower frequency, and would need some improvements to build a stable 8877 amp for 50 MHz. There are papers on buiding a 6 meter amp using this tube; /archives//html/Amps/2004-05/msg00218.html (9,760 bytes)
398. [Amps] strange inquiry for 4CX15,000A use (score: 1): Author: "John T. M. Lyles" <jtml@lanl.gov>; Date: Thu, 27 May 2004 11:20:32 -0600; That question is like asking which refrigerators use brand X compressor, or which trucks use a Cummins (or Fiat) engines. The 4CX15,000A is used (and has been used for many years) in all sorts of tra; /archives//html/Amps/2004-05/msg00250.html (8,479 bytes)
399. [Amps] RF Chokes and Inductor Papers (score: 1): Author: "John T. M. Lyles" <jtml@lanl.gov>; Date: Fri, 4 Jun 2004 12:07:01 -0600; There has been a lot of published work on Solenoidal RF Chokes and related technology in the early radio era, in Proceedings of the IRE and other journals. Harold Wheeler was one of the pioneers. Her; /archives//html/Amps/2004-06/msg00021.html (12,126 bytes)
400. [Amps] Glass Power Tube rebuilders (score: 1): Author: "John T. M. Lyles" <jtml@lanl.gov>; Date: Fri, 4 Jun 2004 12:13:50 -0600; The problem that I have experienced with rebuilders is that they haven't been able to get the glass in sizes that used to be common, i.e., a blank in the size of a 3-1000Z diameter, from Germany (Sho; /archives//html/Amps/2004-06/msg00022.html (7,053 bytes)

Current List: 381 - 400
Page: [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20]