Search String: Display: Description: Sort:

Results:

References: [ +from:gm3sek@ifwtech.co.uk: 471 ]

Total 471 documents matching your query.

221. Re: [Amps] [AMPS] Drake L-4 negative grid current reading on meter (score: 1)
Author: Ian White GM3SEK <gm3sek@ifwtech.co.uk>
Date: Thu, 22 Nov 2007 10:17:45 +0000
The problem with that .82 ohm resistor is the amount of destructive energy that it lets through into the tube, while the resistor is taking its own sweet time to blow. Quite so. (Look at the construc
/archives//html/Amps/2007-11/msg00325.html (10,910 bytes)

222. Re: [Amps] Tranformer Suppliers (score: 1)
Author: Ian White GM3SEK <gm3sek@ifwtech.co.uk>
Date: Sat, 8 Dec 2007 07:32:49 +0000
Try something smaller first - make your own integrated circuits. -- 73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB)... but certainly not going there :-) _________________________________
/archives//html/Amps/2007-12/msg00057.html (9,499 bytes)

223. Re: [Amps] Nicotine from last owner :-( (score: 1)
Author: Ian White GM3SEK <gm3sek@ifwtech.co.uk>
Date: Sat, 8 Dec 2007 10:07:13 +0000
Rather than using that as an alternative method, you may get quicker results by cleaning out the worst places by hand, and then move on to the method Steve suggests. Foaming aerosol cleaner is very g
/archives//html/Amps/2007-12/msg00063.html (9,324 bytes)

224. Re: [Amps] 4CX250 MSDS SHEET (score: 1)
Author: Ian White GM3SEK <gm3sek@ifwtech.co.uk>
Date: Wed, 12 Dec 2007 10:51:29 +0000
"Pink BeO ceramic" is an urban legend. From http://www.svetlana.com/docs/tubeFAQ.html [CAPITALS added for emphasis]: "Q. Why is your ceramic pink? A. Svetlana ceramic power tubes are manufactured wit
/archives//html/Amps/2007-12/msg00139.html (11,108 bytes)

225. Re: [Amps] 4CX250 MSDS SHEET (score: 1)
Author: Ian White GM3SEK <gm3sek@ifwtech.co.uk>
Date: Wed, 12 Dec 2007 13:19:44 +0000
Yes, that all fits together - the 4CX250B"M-for-Marconi". Mike, you probably have all the evidence you need to tear up the beryllium emergency procedure. If the Navy wants more, then call Eimac. 73 f
/archives//html/Amps/2007-12/msg00142.html (14,682 bytes)

226. Re: [Amps] Amplifier Solid State Keying Relay Circuit (score: 1)
Author: Ian White GM3SEK <gm3sek@ifwtech.co.uk>
Date: Thu, 13 Dec 2007 21:55:37 +0000
http://www.ifwtech.co.uk/g3sek/in-prac/best-of.htm#speedup Click the "April 2002" link to download the whole article. -- 73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB) http://www.ifwtec
/archives//html/Amps/2007-12/msg00157.html (9,134 bytes)

227. Re: [Amps] VHF amplifier input network (score: 1)
Author: Ian White GM3SEK <gm3sek@ifwtech.co.uk>
Date: Tue, 18 Dec 2007 08:29:53 +0000
You can think of it as two back-to-back L networks. Analysing it in more detail... The net reactance of VC1-L1 is always inductive. (VC1 is simply a convenient way to make this reactance adjustable;
/archives//html/Amps/2007-12/msg00176.html (9,077 bytes)

228. Re: [Amps] Construction of Light-Weight Wide High VoltageRange High-Pot Testers With Excellent Voltage Resolution (score: 1)
Author: Ian White GM3SEK <gm3sek@ifwtech.co.uk>
Date: Sun, 6 Jan 2008 20:29:41 +0000
Many of the small inverter-type HV generators will operate over a wide range of input voltages. With a variable DC supply voltage (LM317 or similar) the output voltage will vary roughly in proportion
/archives//html/Amps/2008-01/msg00067.html (9,132 bytes)

229. Re: [Amps] Step start (score: 1)
Author: Ian White GM3SEK <gm3sek@ifwtech.co.uk>
Date: Thu, 7 Feb 2008 07:15:41 +0000
A much simpler solution is a slow-blow (T) fuse in series with the current limiting resistor. This idea has been used by Alpha and others for many years. The fuse rating can be about 25% of the long-
/archives//html/Amps/2008-02/msg00036.html (9,834 bytes)

230. Re: [Amps] UK Transformer manufacturer?? (score: 1)
Author: Ian White GM3SEK <gm3sek@ifwtech.co.uk>
Date: Fri, 14 Mar 2008 15:48:55 +0000
It's good. I'd second Steve's recommendation of Harrison & Greenwood. Ian Greenwood is the man to talk to, and they even have a web page now: http://www.hg-transformers.pwp.blueyonder.co.uk/ To confi
/archives//html/Amps/2008-03/msg00122.html (8,225 bytes)

231. Re: [Amps] Fw: AL-80A Problem (score: 1)
Author: Ian White GM3SEK <gm3sek@ifwtech.co.uk>
Date: Fri, 18 Apr 2008 07:18:28 +0100
Almost certainly, the root cause is that the step-start relay is not operating. This leaves the resistor permanently connected in series with the mains, so the original 10W resistor blew and the 25W
/archives//html/Amps/2008-04/msg00236.html (9,818 bytes)

232. Re: [Amps] Higher power transmitting tubes for "portable" amps. (score: 1)
Author: Ian White GM3SEK <gm3sek@ifwtech.co.uk>
Date: Thu, 22 May 2008 07:30:42 +0100
Another example, a monoband (6m) amplifier using an 8877. The whole amplifier - including power supply - goes into a pilot's flight case for hand-carrying, and weighs only 39lbs. With careful tank ci
/archives//html/Amps/2008-05/msg00163.html (8,872 bytes)

233. Re: [Amps] Anyone know RF properties of Acrylic?? (score: 1)
Author: Ian White GM3SEK <gm3sek@ifwtech.co.uk>
Date: Fri, 23 May 2008 08:14:25 +0100
Somewhat... meaning it isn't as low-loss as PTFE, but that doesn't automatically mean you cannot use it Much more important is the electric field strength where you propose to use the material. For e
/archives//html/Amps/2008-05/msg00169.html (8,576 bytes)

234. Re: [Amps] Silver Strap (score: 1)
Author: Ian White GM3SEK <gm3sek@ifwtech.co.uk>
Date: Wed, 9 Jul 2008 08:46:40 +0100
It's the exact opposite. This is one of those long and complicated problems where one small error turns the final answer upside-down - but *two* errors will flip it back again. Stir in all the proble
/archives//html/Amps/2008-07/msg00080.html (9,114 bytes)

235. Re: [Amps] K2RIW / W2GN 144MHz Linear (score: 1)
Author: Ian White GM3SEK <gm3sek@ifwtech.co.uk>
Date: Wed, 9 Jul 2008 18:15:42 +0100
The K2RIW design is for 432MHz only. Fred Merry, W2GN developed a series of designs and kits for 50MHz, 144MHz, 220MHz and 432MHz that all used very similar metalwork except for the tuned circuits. T
/archives//html/Amps/2008-07/msg00087.html (11,187 bytes)

236. Re: [Amps] For Sale: Amplifier Parts (score: 1)
Author: Ian White GM3SEK <gm3sek@ifwtech.co.uk>
Date: Fri, 11 Jul 2008 06:29:23 +0100
Forgive me for asking, but why do we so often see "No sales outside of the USA"? If the buyer pays the extra shipping, it's all the same to the seller. Simply write "Amateur Radio Parts" on a customs
/archives//html/Amps/2008-07/msg00102.html (7,061 bytes)

237. Re: [Amps] Damage? (score: 1)
Author: Ian White GM3SEK <gm3sek@ifwtech.co.uk>
Date: Fri, 25 Jul 2008 20:08:02 +0100
You people are treading dangerously close to the intellectual property of the Gainiax Corporation. Every roll of Gainiax(TM) comes with a big red label: "WARNING: Do Not Connect Ends of Roll Together
/archives//html/Amps/2008-07/msg00266.html (8,696 bytes)

238. Re: [Amps] Tube sources (score: 1)
Author: Ian White GM3SEK <gm3sek@ifwtech.co.uk>
Date: Sat, 26 Jul 2008 07:19:11 +0100
You'd have been looking for the coaxial-based 4CX1600U, which is still available as the GS23B. Unlike the 8938, which is a coaxial-based 8877, the 4CX1600U is a totally different tube from the 1600B,
/archives//html/Amps/2008-07/msg00278.html (9,376 bytes)

239. Re: [Amps] Thoughts on half-wave dipole (score: 1)
Author: Ian White GM3SEK <gm3sek@ifwtech.co.uk>
Date: Mon, 28 Jul 2008 17:40:32 +0100
Since you have already started a large and fruitful discussion on rec.radio.amateur.antenna, why start another one here where it doesn't belong? -- 73 from Ian GM3SEK http://www.ifwtech.co.uk/g3sek _
/archives//html/Amps/2008-07/msg00333.html (8,860 bytes)

240. Re: [Amps] Alpha Ip problem (score: 1)
Author: Ian White GM3SEK <gm3sek@ifwtech.co.uk>
Date: Tue, 5 Aug 2008 08:45:53 +0100
I doubt if it's practical to do the calibration using an ohm-meter alone. However, it certainly can be done by using an external low-voltage supply to push an accurately known current through the ser
/archives//html/Amps/2008-08/msg00022.html (7,700 bytes)


This search system is powered by Namazu