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References: [ +from:amps@txrx.demon.co.uk: 190 ]

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161. [AMPS] Re: Parasitics (score: 1): Author: amps@txrx.demon.co.uk (Steve Thompson); Date: Tue, 19 May 1998 20:19:04 +0100; snip It is true that maximum power transfer occurs when source and load impedances are equal and conjugate, but with power devices it is normal to work by looking at what they do when presented with; /archives//html/Amps/1998-05/msg00360.html (10,103 bytes)
162. [AMPS] Resonances (score: 1): Author: amps@txrx.demon.co.uk (Steve Thompson); Date: Wed, 20 May 1998 08:10:45 +0100; I agree entirely - I just don't have an amp to do it on so I thought I'd see what the individual component looked like. I'd be surprised if the general effects I saw were to change massively when in; /archives//html/Amps/1998-05/msg00374.html (7,751 bytes)
163. [AMPS] smoke (score: 1): Author: amps@txrx.demon.co.uk (Steve Thompson); Date: Thu, 21 May 1998 07:15:26 +0100; Over the weekend, a friend put forward his theory that we've got it all wrong with electrons (and holes):- power devices actually run on smoke. Proof? When the smoke gets out they stop working :-) S; /archives//html/Amps/1998-05/msg00462.html (7,337 bytes)
164. [AMPS] Resonances (score: 1): Author: amps@txrx.demon.co.uk (Steve Thompson); Date: Thu, 21 May 1998 07:35:36 +0100; For sure - 'general' and 'massively' were carefully chosen :-) Steve -- FAQ on WWW: http://www.contesting.com/ampfaq.html Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contes; /archives//html/Amps/1998-05/msg00463.html (8,355 bytes)
165. [AMPS] Airflow (score: 1): Author: amps@txrx.demon.co.uk (Steve Thompson); Date: Sat, 23 May 1998 07:17:38 +0100; Is it permissible to blow air through 3CX800 in the reverse direction to 'normal', i.e. in at the top and out at the bottom of the anode? There's obviously an effect on seal temperatures, but if thes; /archives//html/Amps/1998-05/msg00516.html (7,037 bytes)
166. [AMPS] new transistors for UHF power (score: 1): Author: amps@txrx.demon.co.uk (Steve Thompson); Date: Sun, 24 May 1998 10:13:41 +0100; I've been told that these weren't quite as successful as they appeared. There's no doubt that SiC will make its impact in due course, but I think it's some years away yet; there's a lot of problems m; /archives//html/Amps/1998-05/msg00555.html (8,207 bytes)
167. [AMPS] Sealing of RF chamber (score: 1): Author: amps@txrx.demon.co.uk (Steve Thompson); Date: Sun, 24 May 1998 10:21:35 +0100; I've taken to running 1k resistor(s) from the heater pin(s) to feedthroughs in the compartment wall. There's no risk if the test point gets shorted to chassis, and negligible reading error with a DVM; /archives//html/Amps/1998-05/msg00556.html (8,205 bytes)
168. [AMPS] Airflow (score: 1): Author: amps@txrx.demon.co.uk (Steve Thompson); Date: Mon, 25 May 1998 08:15:30 +0100; Thanks, Tom. I'll check it out; I have a data sheet but I can't get near the cabinet at the moment. I'm sure that somewhere in the 8873/4/5 or 3CX800 data sheets there's a specific comment about the; /archives//html/Amps/1998-05/msg00557.html (8,584 bytes)
169. [AMPS] Triode Amp Out/In isolation (score: 1): Author: amps@txrx.demon.co.uk (Steve Thompson); Date: Thu, 28 May 1998 07:33:16 +0100; You can improve the in/out isolation by tuning the grid inductance; see the articles on 70cm amps by K1FO in the ARRL UHF/Microwave projects manual. Steve -- FAQ on WWW: http://www.contesting.com/amp; /archives//html/Amps/1998-05/msg00612.html (8,879 bytes)
170. [AMPS] Any *Good* Amps? (score: 1): Author: amps@txrx.demon.co.uk (Steve Thompson); Date: Fri, 17 Apr 1998 08:55:19 +0100; snip Has anyone tried a 3CX800 in the MLA2500? Steve G8GSQ -- FAQ on WWW: http://www.contesting.com/ampfaq.html Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com P; /archives//html/Amps/1998-04/msg00151.html (7,444 bytes)
171. [AMPS] parasitics (score: 1): Author: amps@txrx.demon.co.uk (Steve Thompson); Date: Tue, 21 Apr 1998 21:18:27 +0100; Presumably the usual resistive suppressor in series with the anode only works to dampen the vhf resonance when the other end of the suppressor has reasonably low Z path to ground. Is there a case for; /archives//html/Amps/1998-04/msg00208.html (9,278 bytes)
172. [AMPS] parasitics (score: 1): Author: amps@txrx.demon.co.uk (Steve Thompson); Date: Thu, 23 Apr 1998 07:48:42 +0100; I reckon this would be a very shrewd move, maybe 10-20pF or so, even when you plan to use a L match. The low value Rs transforms to a high value shunt R - if the tuning network presents a high impeda; /archives//html/Amps/1998-04/msg00222.html (10,787 bytes)
173. [AMPS] parasitics (score: 1): Author: amps@txrx.demon.co.uk (Steve Thompson); Date: Fri, 24 Apr 1998 08:37:02 +0100; Will this work if the antenna has a high SWR at vhf? Steve -- FAQ on WWW: http://www.contesting.com/ampfaq.html Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com P; /archives//html/Amps/1998-04/msg00271.html (8,826 bytes)
174. [AMPS] Odds (score: 1): Author: amps@txrx.demon.co.uk (Steve Thompson); Date: Fri, 24 Apr 1998 08:42:35 +0100; Sorry to jump backwards: Mike, G0MJW asked if UHF ceramic tubes are more prone to parasitic oscillation problems than glass types - I don't know, but the grid inductance you can't get at in the glass; /archives//html/Amps/1998-04/msg00272.html (7,141 bytes)
175. [AMPS] parasitics (score: 1): Author: amps@txrx.demon.co.uk (Steve Thompson); Date: Mon, 27 Apr 1998 07:22:36 +0100; BIG snip.. I've seen 1 mil (thou) bond wires bend during load pull tests. No, please don't let's start.... Steve -- FAQ on WWW: http://www.contesting.com/ampfaq.html Submissions: amps@contesting.com; /archives//html/Amps/1998-04/msg00302.html (8,867 bytes)
176. [AMPS] parasitics (score: 1): Author: amps@txrx.demon.co.uk (Steve Thompson); Date: Tue, 28 Apr 1998 08:07:24 +0100; And, if there's a parasitic oscillation, it doesn't mean there is a resonance (or that the oscillation is occurring at any resonant frequency if there is one). All it needs is the load on the active; /archives//html/Amps/1998-04/msg00319.html (9,489 bytes)
177. [AMPS] Class E MOSFET Amps (score: 1): Author: amps@txrx.demon.co.uk (Steve Thompson); Date: Wed, 29 Apr 1998 08:12:49 +0100; Class E operation relies on a couple of key points to deliver the high efficiency - the device has to be able to switch very quickly compared to the rf cycles going through it, and the external load; /archives//html/Amps/1998-04/msg00332.html (9,758 bytes)
178. [AMPS] INFO ON ACRIAN S200-50 POWER FET (score: 1): Author: amps@txrx.demon.co.uk (Steve Thompson); Date: Sun, 1 Mar 1998 21:52:01 +0000; These are bipolars, tested at 200W output at 30MHz, 50V supply. A pair should give 300W with reasonable linearity broadband. I can scan and send the data if you wish. Steve G8GSQ (ex Acrian apps. eng; /archives//html/Amps/1998-03/msg00004.html (7,365 bytes)
179. [AMPS] Warm beer (score: 1): Author: amps@txrx.demon.co.uk (Steve Thompson); Date: Thu, 12 Mar 1998 20:12:33 +0000; Lucas are only preserving a long tradition - our style of beer became standard about 500 yrs ago when every household brewed their own as the water was unfit to drink. I make beer and amplifiers too; /archives//html/Amps/1998-03/msg00214.html (6,793 bytes)
180. [AMPS] Step Start for Ameritron AL-80A (score: 1): Author: amps@txrx.demon.co.uk (Steve Thompson); Date: Mon, 16 Mar 1998 07:33:32 +0000; You might consider using current limiting resistors with a higher resistance and power rating, especially where you have a separate HV transformer. If there is a fault which draws high primary curren; /archives//html/Amps/1998-03/msg00317.html (9,312 bytes)

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