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References: [ +from:ka4inm@tampabay.rr.com: 211 ]

Total 211 documents matching your query.

181. Re: [Amps] Any new tube research? (WAS) Re: New NXP BLF578XR 1200W LDMOS FET is "indestructible" (score: 1)
Author: Ron Youvan <ka4inm@tampabay.rr.com>
Date: Sat, 13 Aug 2011 18:02:24 -0400
I think only emissive materials that are more efficient at lower temperatures remain to be exhausted on this area. I do not think developing 30 kW of RF across 6 MHz (ATSC) can be developed with 30,
/archives//html/Amps/2011-08/msg00054.html (10,555 bytes)

182. Re: [Amps] Dahl transformer BC plate transformer center-tap insulation? (score: 1)
Author: Ron Youvan <ka4inm@tampabay.rr.com>
Date: Fri, 02 Sep 2011 09:28:58 -0400
Get the secondary winding Hi-Potted at 10 or 15 kV, don't guess. (hV tested) -- Ron KA4INM - Ifen my mother in law were to boil water it would taste funny ... Earl Pitts 9-1-11 ______________________
/archives//html/Amps/2011-09/msg00005.html (8,085 bytes)

183. Re: [Amps] SB221 Low Output (score: 1)
Author: Ron Youvan <ka4inm@tampabay.rr.com>
Date: Mon, 12 Sep 2011 10:24:10 -0400
I don't know anything about SSB, (what ever that is) but with 25 - 30 Watts of drive you should get about 350 Watts (carrier only) out of it, it looks (to me) like you are over driving it a lot. That
/archives//html/Amps/2011-09/msg00036.html (7,381 bytes)

184. Re: [Amps] Ameritron AL-80B (score: 1)
Author: Ron Youvan <ka4inm@tampabay.rr.com>
Date: Mon, 12 Sep 2011 21:07:59 -0400
Also measure the amplifier drive power on all bands. -- Ron KA4INM - Ifen my mother in law were to boil water it would taste funny ... Earl Pitts 9-1-11 ______________________________________________
/archives//html/Amps/2011-09/msg00049.html (7,138 bytes)

185. Re: [Amps] 2 ways of Gettering... (score: 1)
Author: Ron Youvan <ka4inm@tampabay.rr.com>
Date: Wed, 14 Sep 2011 09:16:54 -0400
Actually yes. I operated a DX-100 for 2 years as a novice and there was no heat. I have seen a vast quantity of broadcast transmitters am and fm operating with no detectable sign of red, but many did
/archives//html/Amps/2011-09/msg00083.html (8,512 bytes)

186. Re: [Amps] 374A will not turn on ??? Suggestions? (score: 1)
Author: Ron Youvan <ka4inm@tampabay.rr.com>
Date: Thu, 13 Oct 2011 13:45:39 -0400
I'm not Lou, but only vacuums, (because of the enclosures) filaments (in vacuums) and chemicals in parts (mostly electrolytic capacitors now-a-days) have a life expectancies. (are expected to fail wi
/archives//html/Amps/2011-10/msg00038.html (9,361 bytes)

187. Re: [Amps] Anodized aluminum (score: 1)
Author: Ron Youvan <ka4inm@tampabay.rr.com>
Date: Mon, 17 Oct 2011 14:52:25 -0400
Plain "aluminum sheeting" oxidizes before it gets out of the machine and is coated with aluminum oxide in seconds and rather well insulated, I see no practical difference other than the greater hardn
/archives//html/Amps/2011-10/msg00048.html (7,803 bytes)

188. Re: [Amps] Gettering - ETAL (score: 1)
Author: Ron Youvan <ka4inm@tampabay.rr.com>
Date: Tue, 08 Nov 2011 09:44:52 -0500
You can't run the finned plate of an air cooled plate orange or red, so the MFGs spot weld gettering washers and disks to the leads between the base and under side the elements. (operating the plate
/archives//html/Amps/2011-11/msg00032.html (7,776 bytes)

189. Re: [Amps] Increased ambient noise in a 2 x 8877 amplifier (score: 1)
Author: Ron Youvan <ka4inm@tampabay.rr.com>
Date: Wed, 16 Nov 2011 21:24:58 -0500
One can only guess, it is possible some insulation is breaking down under the hV. If you can operate the amplifier with the valves on the shelf you might prove or disprove it. You can also Hi-Pot the
/archives//html/Amps/2011-11/msg00069.html (9,322 bytes)

190. Re: [Amps] Sucking air (score: 1)
Author: Ron Youvan <ka4inm@tampabay.rr.com>
Date: Tue, 29 Nov 2011 10:09:14 -0500
Plastic fan over hot air, that sounds like a bad idea. Metal fan with oiled bearings over hot air, that sounds like a bad idea. Add more air flow to the input of the existing fan if possible. -- Ron
/archives//html/Amps/2011-11/msg00167.html (7,810 bytes)

191. Re: [Amps] Can distilled water be used for a dummy load ?? (score: 1)
Author: Ron Youvan <ka4inm@tampabay.rr.com>
Date: Tue, 29 Nov 2011 10:16:48 -0500
Distilled ONLY and steam distilled is greatly preferred. (over de-mineralized) When hot the H2O will expand much more, possibly steam and some can get lost. Oil is better. Buy "mineral oil" from any
/archives//html/Amps/2011-11/msg00170.html (10,470 bytes)

192. Re: [Amps] Linear Amplifier Tuning---PROPERLY! (score: 1)
Author: Ron Youvan <ka4inm@tampabay.rr.com>
Date: Tue, 20 Dec 2011 13:04:09 -0500
I think I understand the procedure, is it quite bad to under-couple the output of any amplifier, this is like "loosing the load." (something gone open) When the load is any less than optimum the devi
/archives//html/Amps/2011-12/msg00164.html (9,691 bytes)

193. Re: [Amps] Shipment of large old tubes (score: 1)
Author: Ron Youvan <ka4inm@tampabay.rr.com>
Date: Wed, 21 Dec 2011 17:23:36 -0500
Every package that I have ever received with these stuck on them have had the business parts ripped off. I wonder who would want to do that? -- Ron KA4INM - Did you know ... ... that no-one ever read
/archives//html/Amps/2011-12/msg00182.html (9,018 bytes)

194. Re: [Amps] Anti-Corona Paint (score: 1)
Author: Ron Youvan <ka4inm@tampabay.rr.com>
Date: Sun, 25 Dec 2011 10:20:58 -0500
Depending on use, I use "Red silicone `gasket maker" compound" from the auto parts stores and Walmart for most of my sealing, gluing and protection jobs. Once cured it is very insulative. I think it
/archives//html/Amps/2011-12/msg00207.html (8,468 bytes)

195. Re: [Amps] plate choke location (score: 1)
Author: Ron Youvan <ka4inm@tampabay.rr.com>
Date: Fri, 06 Jan 2012 12:06:02 -0500
That is done with many push-pull amplifiers, (some push-pull amplifiers don't have a plate choke or DC coupling capacitors for that matter) but: All insulation (theirs-a-bouts) would have to be adequ
/archives//html/Amps/2012-01/msg00091.html (8,215 bytes)

196. Re: [Amps] IMD (score: 1)
Author: Ron Youvan <ka4inm@tampabay.rr.com>
Date: Sun, 08 Jan 2012 09:35:01 -0500
This "different delay for different frequencies" is called "group delay." It is something that messes up dial up modems. (so you don't get 56 kB/s) -- Ron KA4INM - Did you know ... ... that no-one ev
/archives//html/Amps/2012-01/msg00104.html (10,362 bytes)

197. Re: [Amps] RF clipping for SSB (score: 1)
Author: Ron Youvan <ka4inm@tampabay.rr.com>
Date: Thu, 12 Jan 2012 12:33:19 -0500
Most "rice boxes" have used IF or RF audio clipping and or compression for many many years. -- Ron KA4INM - Ron KA4INM - Did you know ... ... that no-one ever reads these things? ____________________
/archives//html/Amps/2012-01/msg00130.html (7,493 bytes)

198. [Amps] I hope this is not new only to me ... (score: 1)
Author: Ron Youvan <ka4inm@tampabay.rr.com>
Date: Sat, 21 Jan 2012 11:17:20 -0500
... I got a new MFJ catalog in the mail yesterday and it has several pages of amplifier building parts. I have never seen this before. I always downloaded the instruction book of something similar an
/archives//html/Amps/2012-01/msg00161.html (6,920 bytes)

199. Re: [Amps] 3CX800A7 Grid Current Problem (score: 1)
Author: Ron Youvan <ka4inm@tampabay.rr.com>
Date: Sat, 28 Jan 2012 09:16:07 -0500
I'm pretty sure ceramic materials like ferrites can't be damaged by mild heating when enough heating to shatter them doesn't change the magnetic properties, after being epoxied back together the work
/archives//html/Amps/2012-01/msg00224.html (10,091 bytes)

200. Re: [Amps] 4CX1000A (score: 1)
Author: Ron Youvan <ka4inm@tampabay.rr.com>
Date: Sat, 28 Jan 2012 15:23:00 -0500
I'm not mike, but I think the reverse screen current is not strictly normal, in a perfectly built tube you should see none. These tube are built with the screen grid components hiding in the electron
/archives//html/Amps/2012-01/msg00231.html (10,387 bytes)

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