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181. [AMPS] SB-1000 mods? (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Fri, 7 Sep 2001 20:11:16 -0400
work, but thousands are in use. I have always added You'd be far better off to use a HV glitch resistor, and leave the grid grounded. Resistors in grid leads are bad news unless there is good reason
/archives//html/Amps/2001-09/msg00113.html (8,517 bytes)

182. [AMPS] SB-1000 mods? (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Fri, 7 Sep 2001 23:04:33 -0400
A .82 ohm resistor is not a glitch resistor or a fuse. Fuses are bad enough because of time delay and internal arcing, and resistors make very poor fuses. Ian's website has good reliable information
/archives//html/Amps/2001-09/msg00116.html (8,674 bytes)

183. [AMPS] glitch resistors (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Sat, 8 Sep 2001 08:48:14 -0400
That's not a solution I'm afraid. When you have an arc, the resistor MUST be able to handle the full supply voltage across the terminals of the resistor no matter where it is located in the path. Th
/archives//html/Amps/2001-09/msg00121.html (8,430 bytes)

184. [AMPS] SB-1000 mods? (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Sat, 8 Sep 2001 08:48:14 -0400
Hi George, Filling the fuse with sand (HV fuse) does not address the long delay time as the fuse opens, nor the unreliability in fusing current. It does allow the fuse to eventually open and quench
/archives//html/Amps/2001-09/msg00122.html (10,675 bytes)

185. [AMPS] True Or Not True #2 (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Sat, 8 Sep 2001 15:35:07 -0400
Good CW ops can hear well below noise. It is common. -2dB is really not anything exceptional at all Phil. I can clearly hear a tone and copy CW when the noise power is ten dB greater than the tone p
/archives//html/Amps/2001-09/msg00139.html (8,753 bytes)

186. [AMPS] SB-1000 mods? (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Sat, 8 Sep 2001 15:35:07 -0400
My homemade PA has a pair of 50 ohm ~200 watt very long carbon resistors in parallel. It dumps a primary disconnect during a fault of over 5 amperes. Normally all I hear is a little faint tic as it
/archives//html/Amps/2001-09/msg00140.html (9,209 bytes)

187. [AMPS] SB-1000 mods? (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Sat, 8 Sep 2001 15:35:07 -0400
The resistor must be surge rated for the voltage across the resistor and the peak energy. RCD makes xxx-P series pulse rated resistors, or you can use a "glow-bar" type. The RCD pulse rated resistor
/archives//html/Amps/2001-09/msg00141.html (9,666 bytes)

188. [AMPS] glitch resistors (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Sat, 8 Sep 2001 15:35:06 -0400
Hi Kim, Thats not correct - why you forget the selfinduction in the trafo ! The high dump current ideally never makes it to the transformer. It comes from the capacitor. If you have put the glitch re
/archives//html/Amps/2001-09/msg00142.html (9,572 bytes)

189. [AMPS] GLITCH RESISTORS - SOURCE (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Sun, 9 Sep 2001 07:57:26 -0400
Not speaking of a specific resistor, but any resistor in general... There is no reason to waste money on non-inductive resistors for glitch. Actually the inductance, if anything, helps but only very
/archives//html/Amps/2001-09/msg00155.html (8,256 bytes)

190. [AMPS] SB-1000 mods? (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Mon, 10 Sep 2001 13:16:39 -0400
RCD? I'd suggest people check manufacturers. I'm sure many have stock components that will do. For example, Ameritron has a variety of globar resistors and also a 400 joule 13 watt dissipation 1500
/archives//html/Amps/2001-09/msg00185.html (9,775 bytes)

191. [AMPS] sb-200 band switch (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Tue, 11 Sep 2001 20:44:15 -0400
Wafers from the AL80B switch can be moved to the SB-200 if you have a damaged wafer. 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.c
/archives//html/Amps/2001-09/msg00204.html (7,135 bytes)

192. [AMPS] SB-1000 mods? (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Tue, 11 Sep 2001 20:44:15 -0400
The 4 by 5 will have higher voltage, but the tube will easily handle more impact than a small tube. Every system needs to be looked at in view of the total system. There is no average plate choke. T
/archives//html/Amps/2001-09/msg00205.html (9,456 bytes)

193. [AMPS] Henry 2KD classic (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Wed, 12 Sep 2001 07:55:25 -0400
Hi Steve, How do you know the amplifier is "taking off"? What are the symptoms? 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Adm
/archives//html/Amps/2001-09/msg00213.html (8,858 bytes)

194. [AMPS] Henry 2kd classic (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Wed, 12 Sep 2001 10:22:48 -0400
I'd just make it as big as I reasonably could, depending on plate current. There really isn't any reason to dissipate more than a couple percent of the output power in the resistor from I^2 R losses
/archives//html/Amps/2001-09/msg00218.html (9,118 bytes)

195. [AMPS] amazing doubletalk... (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Thu, 13 Sep 2001 12:33:33 -0400
Actually, you can go further than that. Arcs inside tubes are almost always NOT caused by parasitics. In order to have an arc, we all know the peak voltage between two points has to exceed the break
/archives//html/Amps/2001-09/msg00231.html (9,698 bytes)

196. [AMPS] gettering (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Thu, 13 Sep 2001 21:40:38 -0400
This has been covered a dozen times on this reflector. The 3-500 gettering agent is zirconium, the gray powder-looking coating on the anode. It is sprayed on, and activates at about 1000 degrees C.
/archives//html/Amps/2001-09/msg00238.html (8,784 bytes)

197. [AMPS] Henry 2kd classic (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Fri, 14 Sep 2001 12:59:43 -0400
There are always risks when we change things in marginally stable systems unless you just buckle down and do everything correctly. If I owned a 30L1 I'd use "cathode" bias and ground the grids norma
/archives//html/Amps/2001-09/msg00251.html (7,502 bytes)

198. [AMPS] amazing doubletalk... (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Sat, 15 Sep 2001 06:32:20 -0400
Eimac (at that time it was Varian) like all other companies is not allowed to give a "strange caller" personal information about employees. Many employees at Eimac also already know Rich pretty well
/archives//html/Amps/2001-09/msg00263.html (9,336 bytes)

199. [AMPS] IMD (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Tue, 18 Sep 2001 07:39:18 -0400
The TS2000 is not a good example. It is exceptionally poor. It is one step removed from class C performance. We have to remember a two-tone test does not show IMD caused by poor dynamic power supply
/archives//html/Amps/2001-09/msg00299.html (9,500 bytes)

200. [AMPS] IMD (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Tue, 18 Sep 2001 10:28:40 -0400
That's right, my IC-751's get worse at low power. I find that a common trait in systems with solid state amplifiers. In the case of the 751A, changed driver transistors and revising the bias system
/archives//html/Amps/2001-09/msg00313.html (8,966 bytes)


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