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References: [ +from:df3kv@t-online.de: 314 ]

Total 314 documents matching your query.

281. Re: [Amps] Cheap auxiliary amp cooling (score: 1)
Author: "Peter Voelpel" <df3kv@t-online.de>
Date: Mon, 2 Apr 2012 00:42:34 +0200
There is no free lunch, either use triodes with low ZSAC and small gain or tetrodes with 20db+ gain and high demand of ZSAC. I have no problem to let my YL1056 idle with 1100W ZSAC and use the same t
/archives//html/Amps/2012-04/msg00008.html (10,744 bytes)

282. Re: [Amps] amp cooling / triodes vs tetrodes (score: 1)
Author: "Peter Voelpel" <df3kv@t-online.de>
Date: Wed, 4 Apr 2012 04:31:53 +0200
Why should one care about an amplifier without EBS or high idle current at all? That current is only drawn if actually transmitting and not in standby mode without output power. 73 Peter, DJ7WW Not t
/archives//html/Amps/2012-04/msg00047.html (10,508 bytes)

283. Re: [Amps] amp cooling / triodes vs tetrodes (score: 1)
Author: "Peter Voelpel" <df3kv@t-online.de>
Date: Wed, 4 Apr 2012 07:56:26 +0200
I donīt think that there is enough heat wasted between words that it worth to do something about it, in my opinion it is never a lot of additional wasted power between words on normal talk. On pauses
/archives//html/Amps/2012-04/msg00048.html (12,833 bytes)

284. Re: [Amps] amp cooling / triodes vs tetrodes (score: 1)
Author: "Peter Voelpel" <df3kv@t-online.de>
Date: Wed, 4 Apr 2012 18:40:40 +0200
When operating DR1A I do as well, but release it on pauses. 73 Peter Many use a foot switch Carl KM1H _______________________________________________ Amps mailing list Amps@contesting.com http://list
/archives//html/Amps/2012-04/msg00052.html (13,774 bytes)

285. Re: [Amps] Filter Capacitors (score: 1)
Author: "Peter Voelpel" <df3kv@t-online.de>
Date: Tue, 17 Apr 2012 13:07:31 +0200
The use of 162ĩF @3.6KV as well 73 Peter, DJ7WW _______________________________________________ Amps mailing list Amps@contesting.com http://lists.contesting.com/mailman/listinfo/amps
/archives//html/Amps/2012-04/msg00166.html (7,898 bytes)

286. Re: [Amps] Capacitors vs No Capacitors (score: 1)
Author: "Peter Voelpel" <df3kv@t-online.de>
Date: Tue, 24 Apr 2012 02:47:38 +0200
In Germany the limit is 750W measured at the tx output. 73 Peter, DJ7WW But remember for most of Europe, full legal limit QRO is rather less then 1500W, (400W limit here in the UK, measured at the fe
/archives//html/Amps/2012-04/msg00224.html (7,642 bytes)

287. Re: [Amps] The power of an oversized electrolytic capacitor / how much PS filter C is enough? (score: 1)
Author: "Peter Voelpel" <df3kv@t-online.de>
Date: Fri, 11 May 2012 00:16:06 +0200
Here we can use the three phases for any purpose we intend to. Maximum power is 55KVA with my installation. In my HV power supply the 2ĩF capacitor is plenty, without it ripple voltage is 4%. 73 Pete
/archives//html/Amps/2012-05/msg00256.html (10,378 bytes)

288. Re: [Amps] The power of an oversized electrolytic capacitor / (score: 1)
Author: "Peter Voelpel" <df3kv@t-online.de>
Date: Sat, 19 May 2012 17:30:52 +0200
I certainly did. I looked up what the commercials did. No large glitch resistor, just current sensor and fast cut off for the transformers. All have choke filter inputs, so have mine. The largest fil
/archives//html/Amps/2012-05/msg00301.html (9,295 bytes)

289. Re: [Amps] The power of an oversized electrolytic capacitor / (score: 1)
Author: "Peter Voelpel" <df3kv@t-online.de>
Date: Mon, 21 May 2012 16:31:15 +0200
My result on a 3-phase power supply with a 3800V AC transformer is a drop to 5162V from 5400VDC at 2.4A load. The capacitor is just 2ĩF, no choke input in this one. That capacitor does the same as a
/archives//html/Amps/2012-05/msg00307.html (9,708 bytes)

290. Re: [Amps] Pi-L Network Question (score: 1)
Author: "Peter Voelpel" <df3kv@t-online.de>
Date: Mon, 18 Jun 2012 19:03:16 +0200
Itīs the opposite. The required capacitance of the load-C of a simple Pi network is much larger then that of a Pi-L, a big advantage beside the much besser harmonic supression and easier tuning. The
/archives//html/Amps/2012-06/msg00242.html (8,613 bytes)

291. Re: [Amps] Pi-L Network Question (score: 1)
Author: "Peter Voelpel" <df3kv@t-online.de>
Date: Mon, 18 Jun 2012 20:06:19 +0200
Hi Jim, Paul,WD7S is using Pi-L with his 8877 autotune allband amp, his layout looks quite practical to me. The tank layout is also linked on that page: http://home.earthlink.net/~wd7s/gallery-5a.htm
/archives//html/Amps/2012-06/msg00249.html (10,792 bytes)

292. Re: [Amps] 4CX1500B's -- worth using? (score: 1)
Author: "Peter Voelpel" <df3kv@t-online.de>
Date: Wed, 20 Jun 2012 22:02:45 +0200
I built a 4CX1000A push-pull amp for 2m in the past, it did about 3KW+ output and was extremely clean. A couple of friends built them also with the same experience. 73 Peter, DJ7WW --Original Message
/archives//html/Amps/2012-06/msg00300.html (9,124 bytes)

293. Re: [Amps] 4CX1500B's -- worth using? (score: 1)
Author: "Peter Voelpel" <df3kv@t-online.de>
Date: Thu, 21 Jun 2012 00:32:01 +0200
That less output is caused by the load line used with Eimacs specification which is more A then AB1 resulting in lower efficiency and lower intermodulation distortion. The 4CX1500B however can be dri
/archives//html/Amps/2012-06/msg00304.html (8,853 bytes)

294. Re: [Amps] 4CX1500B's -- worth using? (score: 1)
Author: "Peter Voelpel" <df3kv@t-online.de>
Date: Thu, 21 Jun 2012 00:35:21 +0200
And the 5CX1500A is used in mine, nice tube as well 73 Peter, DJ7WW That's why my HB linear has a 4CX1500A. David KW4DH _______________________________________________ Amps mailing list Amps@contesti
/archives//html/Amps/2012-06/msg00305.html (12,359 bytes)

295. Re: [Amps] 4CX1500B's -- worth using? OFF LIST (score: 1)
Author: "Peter Voelpel" <df3kv@t-online.de>
Date: Thu, 21 Jun 2012 02:44:26 +0200
I could take pictures, none available at present. It is a 20m mono band amp, a modified plasma generator by Perkin Elmer, the 3000D. I will build amps for other bands too, as I obtained some more tub
/archives//html/Amps/2012-06/msg00314.html (9,846 bytes)

296. Re: [Amps] corona on a quad (score: 1)
Author: "Peter Voelpel" <df3kv@t-online.de>
Date: Fri, 13 Jul 2012 11:16:02 +0200
Fibreglass is a very poor isolator, especially when wet. It turned into flames at the 1KW level already when I used it at a high impedance point. 1 5/8" cable is rated for 32KW@30MHz permanent power
/archives//html/Amps/2012-07/msg00185.html (9,179 bytes)

297. Re: [Amps] Dedicated RF (score: 1)
Author: "Peter Voelpel" <df3kv@t-online.de>
Date: Mon, 30 Jul 2012 04:40:45 +0200
Donīt underrate the development problems with solid state amps doing the same power as two or three 3CPX800A7 or similar. One of the big problems is the low pass filter, high power Micas or NP0 ceram
/archives//html/Amps/2012-07/msg00382.html (9,620 bytes)

298. Re: [Amps] Dedicated RF (score: 1)
Author: "Peter Voelpel" <df3kv@t-online.de>
Date: Mon, 30 Jul 2012 04:55:14 +0200
A pair of MRFE6VP61K25H does 1.8KW on 2m quite nicely with IMD3 better then -40db. On HF itīs a bit difficult to get them working as far I know. 73 Peter, DJ7WW one tone, 9-46 db pep) it has to be se
/archives//html/Amps/2012-07/msg00383.html (8,082 bytes)

299. Re: [Amps] 3CX1500A7/8877 vs el cheapo GS-35B (score: 1)
Author: "Peter Voelpel" <df3kv@t-online.de>
Date: Tue, 31 Jul 2012 14:29:54 +0200
With the air variables most problems are with the rotor contacts, better to use split-stator but used as load capacitors they become too bulky. Two years ago I had a problem on 10m with the vacuum an
/archives//html/Amps/2012-07/msg00440.html (8,375 bytes)

300. Re: [Amps] Lowering the voltage on a transformer (score: 1)
Author: "Peter Voelpel" <df3kv@t-online.de>
Date: Thu, 2 Aug 2012 16:56:59 +0200
Just step it down on the primary with a 90V auto transformer before touching the hv windings 73 Peter, DJ7WW Hi I just get my hands on a nice transformer but the volttage is too high. The transformer
/archives//html/Amps/2012-08/msg00054.html (8,013 bytes)


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