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References: [ +from:K8RI@rogerhalstead.com: 562 ]

Total 562 documents matching your query.

321. Re: [Amps] pre-distortion (score: 1)
Author: "Roger (K8RI)" <k8ri@rogerhalstead.com>
Date: Sun, 19 Oct 2014 03:42:54 -0400
Warren, Thank you very much for this note. By profession and degree I'm a software engineer although having retired in 97, I'm afraid I've fallen far behind on both the hardware and software. I retir
/archives//html/Amps/2014-10/msg00179.html (11,518 bytes)

322. Re: [Amps] Nonlinear Thoughts (score: 1)
Author: "Roger (K8RI)" <k8ri@rogerhalstead.com>
Date: Thu, 23 Oct 2014 12:08:07 -0400
Thoughts on computer heatsinks and cooling I am running 240 watt CPUs. 8 core @ 4.3 to 5 GHz. with 16 to 32 GB of RAM Several are liquid cooled (closed circuit) and run in the 40C range compared to t
/archives//html/Amps/2014-10/msg00221.html (22,724 bytes)

323. Re: [Amps] AL1200 on AM - max carrier? (score: 1)
Author: "Roger (K8RI)" <k8ri@rogerhalstead.com>
Date: Thu, 30 Oct 2014 19:02:50 -0400
A note on tuning amps for maximum out, or the legal limit on the SSB ot CW/tune position? There are many amps, particularly older ones with a tune and SSB position as well as many of today's minimal
/archives//html/Amps/2014-10/msg00264.html (15,000 bytes)

324. Re: [Amps] Alpha 8410 using 4CX1500B - why? (score: 1)
Author: "Roger (K8RI)" <k8ri@rogerhalstead.com>
Date: Sat, 01 Nov 2014 00:17:00 -0400
I don't remember the tube designations any more as it's been 30 plus years since I worked on them, but we ran 200 - 250 KW as an oscillator, induction heater. They were heavy (compared to an 8877, 4C
/archives//html/Amps/2014-11/msg00000.html (8,680 bytes)

325. Re: [Amps] 572B - News? (score: 1)
Author: "Roger (K8RI)" <k8ri@rogerhalstead.com>
Date: Fri, 07 Nov 2014 23:24:49 -0500
If you know someone with a lathe, it is very easy to make transverse coolers/radiators for the Gi7Bso they would work much like the original tubes. 73 Roger (K8RI) Hi, Gustavo! Thanks for the tip, de
/archives//html/Amps/2014-11/msg00017.html (10,784 bytes)

326. Re: [Amps] Holding a vacuum (score: 1)
Author: "Roger (K8RI)" <k8ri@rogerhalstead.com>
Date: Tue, 02 Dec 2014 04:23:08 -0500
One example is the PL-172/8295A. Basically the same tube and the PL-172 has the 8295 designation as well, BUT the PL-172 is a metal, external anode, Pentode with the anode seal made of glass.. The 82
/archives//html/Amps/2014-12/msg00013.html (10,040 bytes)

327. Re: [Amps] Experience with Heart Pacemakers? (score: 1)
Author: "Roger (K8RI)" <k8ri@rogerhalstead.com>
Date: Sun, 07 Dec 2014 13:30:37 -0500
As I said below, You can research it on-line as most manufacturers have sites and pamphlets.and always ask your physician.. SOME of the older ones were bothered by high power HF. Some, like mine use
/archives//html/Amps/2014-12/msg00043.html (12,346 bytes)

328. Re: [Amps] The genius of ham radio (score: 1)
Author: "Roger (K8RI)" <k8ri@rogerhalstead.com>
Date: Mon, 12 Jan 2015 01:22:31 -0500
When established theory and practice don't agree the the person who says that, doesn't understand the theory, did the experiment wrong, or both. As Jim quoted: His point was that "everything 'works,'
/archives//html/Amps/2015-01/msg00033.html (10,044 bytes)

329. Re: [Amps] The genius of ham radio (score: 1)
Author: "Roger (K8RI)" <k8ri@rogerhalstead.com>
Date: Mon, 12 Jan 2015 23:40:56 -0500
Aren't proven theories then referred to as physical laws? 73 Roger (K8RI) On 1/12/2015 12:58 PM, Jim Brown wrote: On Mon,1/12/2015 8:36 AM, greg greene wrote: the difference between theory and practi
/archives//html/Amps/2015-01/msg00067.html (14,283 bytes)

330. Re: [Amps] The genius of ham radio (score: 1)
Author: "Roger (K8RI)" <k8ri@rogerhalstead.com>
Date: Tue, 13 Jan 2015 17:40:52 -0500
I have them back for quite a ways. Even have a few contributions. Mainly I look for changes in construction articles and it's a good place to learn about new digital modes and equipment . The books r
/archives//html/Amps/2015-01/msg00099.html (12,222 bytes)

331. Re: [Amps] Multi-tube vs Single or Dual-tube amps? (score: 1)
Author: "Roger (K8RI)" <k8ri@rogerhalstead.com>
Date: Mon, 19 Jan 2015 18:04:31 -0500
The design needs to take into consideration the characteristics of the tube(s) and allow for such, In the case of the Emtron DX-2so ans DX-3sp the bias is set for each tube individually. The closer t
/archives//html/Amps/2015-01/msg00160.html (11,453 bytes)

332. Re: [Amps] High Voltage Wire (score: 1)
Author: "Roger (K8RI)" <k8ri@rogerhalstead.com>
Date: Mon, 19 Jan 2015 20:10:29 -0500
When I was a senior in high school (long time ago), I had a a so called "full house", V-8 in my car. My girlfriend's dad always knew what time she got home as that ignition would wipe out his TV set
/archives//html/Amps/2015-01/msg00164.html (11,743 bytes)

333. Re: [Amps] Multi-tube vs Single or Dual-tube amps? (score: 1)
Author: "Roger (K8RI)" <k8ri@rogerhalstead.com>
Date: Tue, 20 Jan 2015 05:40:58 -0500
But in "those days" they didn't worry about matching tube in a lot of amp, or IM for that matter. On one hand we had the 32S* series and KWM-2 at 50 db IM or less, while on the other we had 19 sweep
/archives//html/Amps/2015-01/msg00176.html (12,268 bytes)

334. Re: [Amps] Multi-tube vs Single or Dual-tube amps? (score: 1)
Author: "Roger (K8RI)" <k8ri@rogerhalstead.com>
Date: Tue, 20 Jan 2015 17:05:12 -0500
There are many things we can do, and in the time of the commercial multi tube amps things like IM products were ignored. Many thing worked in spite of ignoring good practice. I ran grid drive with a
/archives//html/Amps/2015-01/msg00185.html (12,785 bytes)

335. Re: [Amps] ceramic vs glass (score: 1)
Author: "Roger (K8RI)" <k8ri@rogerhalstead.com>
Date: Sat, 24 Jan 2015 22:21:57 -0500
It has been my experience, hence anecdotal, that if properly cooled and treated, there is little difference in the useful life of Ceramic Vs glass tubes, but when we get into older tubes, like the PL
/archives//html/Amps/2015-01/msg00268.html (10,448 bytes)

336. Re: [Amps] 5 Minutes for Ameritron 811H to warm up? (score: 1)
Author: "Roger (K8RI)" <k8ri@rogerhalstead.com>
Date: Mon, 26 Jan 2015 01:01:08 -0500
When it comes to seals, as noted, glass to metal is an art. At best, the glass is not a perfect bond to the metal. We are talking clearances that are so small, a molecule of gas may take months or ye
/archives//html/Amps/2015-01/msg00289.html (12,047 bytes)

337. Re: [Amps] {Collins} Understanding Screen Current in a Tetrode (score: 1)
Author: "Roger (K8RI)" <k8ri@rogerhalstead.com>
Date: Wed, 28 Jan 2015 03:56:27 -0500
On 1/27/2015 9:26 PM, Carl wrote: I don't care for that JI answer since grid driven tetrodes are almost always run in AB1 where there is no grid current and in AB2 there is only a flicker of current
/archives//html/Amps/2015-01/msg00333.html (21,168 bytes)

338. Re: [Amps] Understanding Screen Current in a tetrode (score: 1)
Author: "Roger (K8RI)" <k8ri@rogerhalstead.com>
Date: Wed, 28 Jan 2015 04:00:55 -0500
Those old rigs come from an era where no one paid much attention to IM products and the signals from many of the "sweep tube" rigs was pretty bad. 73 Roger (K8RI) When I ran a pair of 4CX250B's on Tw
/archives//html/Amps/2015-01/msg00334.html (8,503 bytes)

339. Re: [Amps] Topband: Elimination of Treadmill RFI on 160 meters (score: 1)
Author: "Roger (K8RI)" <k8ri@rogerhalstead.com>
Date: Thu, 29 Jan 2015 04:51:22 -0500
As for the thermal compound, it depends on the compound. I use Arctic Silver which cures after an hour or two of use, giving the appearance of being dried out. It's supposed to look (and feel) that w
/archives//html/Amps/2015-01/msg00355.html (11,215 bytes)

340. Re: [Amps] Astron Power Supply replies (score: 1)
Author: "Roger (K8RI)" <k8ri@rogerhalstead.com>
Date: Thu, 29 Jan 2015 05:06:42 -0500
Check your voltage "TO" the pass transistors. If it's high the transistors will run hot. IIRC the VS and RS use the sane control circuit, but it's been quite a while since I had one apart. Please NOT
/archives//html/Amps/2015-01/msg00356.html (11,898 bytes)


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