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Total 246 documents matching your query.

1. Re: [Amps] 4 x Glass Glowing tubes (score: 1)
Author: Ron Youvan <ka4inm@gmail.com>
Date: Tue, 28 Feb 2012 10:31:33 -0500
I wasn't asked, but I would vote on the four GU48/833A, (triode) with push-pull paralleled pairs. A muffin fan is all that you need to get the heat out of the box. -- 73 Ron KA4INM - All E-mail sent
/archives//html/Amps/2012-02/msg00314.html (11,215 bytes)

2. Re: [Amps] Bleeders (score: 1)
Author: Ron Youvan <ka4inm@gmail.com>
Date: Wed, 29 Feb 2012 10:56:02 -0500
This idea is along the lines of what has been used in many high power broadcast amplifiers for over 50 years. (guillotine style) Except they use/d a solenoid to wind up a spring that hit a micro-swit
/archives//html/Amps/2012-02/msg00339.html (7,911 bytes)

3. Re: [Amps] 4 x GU-81 Grounded Grid Penthodes (score: 1)
Author: Ron Youvan <ka4inm@gmail.com>
Date: Fri, 02 Mar 2012 20:12:24 -0500
You can always use DC on an indirectly heated cathode, but with a directly heated filament you must consider the fact that one end of the "cathode" will have 12.6 Volts more or less cathode to grid b
/archives//html/Amps/2012-03/msg00041.html (9,518 bytes)

4. Re: [Amps] 6kW Coax (score: 1)
Author: Ron Youvan <ka4inm@gmail.com>
Date: Sun, 11 Mar 2012 16:38:09 -0400
Actually, with everything being the same the lowest loss is from the highest impedance possible for the form factor, the highest power handling capacity is from the lowest impedance. 75 Ohms coax has
/archives//html/Amps/2012-03/msg00127.html (8,467 bytes)

5. Re: [Amps] RF coupling to 8877 filaments? (score: 1)
Author: Ron Youvan <ka4inm@gmail.com>
Date: Tue, 13 Mar 2012 22:26:04 -0400
I think filament chokes are used with cathode driven amplifiers only. I have never heard of using them with grid driven amplifiers. The only alternate that I have ever heard of is threading one condu
/archives//html/Amps/2012-03/msg00163.html (8,251 bytes)

6. Re: [Amps] Guidelines.....toroids for tank ckts (score: 1)
Author: Ron Youvan <ka4inm@gmail.com>
Date: Mon, 26 Mar 2012 21:46:29 -0400
Because of the high oil content. The foil can easily be removed, (with a finger nail) I always do for every jar that I open. -- 73 Ron KA4INM - All E-mail sent to this address shall linger in the Goo
/archives//html/Amps/2012-03/msg00275.html (8,883 bytes)

7. Re: [Amps] How to know when filter caps begin to fail (score: 1)
Author: Ron Youvan <ka4inm@gmail.com>
Date: Wed, 28 Mar 2012 21:51:27 -0400
When I was in school (electronics school) we had a wise guy that tore apart "5 tube all American's" for the dual 150 Volt electrolytics with three leads molded in, (at home) he would go into an unuse
/archives//html/Amps/2012-03/msg00333.html (8,949 bytes)

8. Re: [Amps] How Do You Know When Filter Caps Begin to Fail? (score: 1)
Author: Ron Youvan <ka4inm@gmail.com>
Date: Wed, 28 Mar 2012 23:40:26 -0400
Electrolytic capacitors and light bulbs are the only items in a HAM amplifier (or almost anything else) that have a pre-determined life expectancy. It doesn't mater if 99% of ham amplifiers use brute
/archives//html/Amps/2012-03/msg00341.html (10,432 bytes)

9. Re: [Amps] Longshot - looking for 8873 (score: 1)
Author: Ron Youvan <ka4inm@gmail.com>
Date: Fri, 06 Apr 2012 18:52:08 -0400
All of this talk of converting them to another tube makes me wonder if this isn't a good candidate for a water cooled tube. They can operate very quietly also. -- 73 Ron KA4INM - All E-mail sent to t
/archives//html/Amps/2012-04/msg00080.html (7,570 bytes)

10. Re: [Amps] More Capacitors vs LC filters (score: 1)
Author: Ron Youvan <ka4inm@gmail.com>
Date: Thu, 19 Apr 2012 19:14:54 -0400
There is a difference between the "maximum" and the "working" Voltage rating of a capacitor. -- 73 Ron KA4INM - All E-mail sent to this address shall linger in the Google cloud forever! _____________
/archives//html/Amps/2012-04/msg00190.html (8,870 bytes)

11. Re: [Amps] Fwd: Re: soldering vs crimping (score: 1)
Author: Ron Youvan <ka4inm@gmail.com>
Date: Thu, 03 May 2012 19:44:59 -0400
I was taught (at a TV station) how to put PL-259's on with a single edged razor blade, that and a big soldering gun. (I still do) We did hundreds a day each, usually in a party of 4 or 5. -- 73 Ron K
/archives//html/Amps/2012-05/msg00139.html (10,173 bytes)

12. Re: [Amps] The power of an over sized electrolytic capacitor / how much PS filter C is enough? (score: 1)
Author: KA4INM <ka4inm@gmail.com>
Date: Thu, 10 May 2012 11:00:49 -0400
/*snip*/ We also need to take into account the fact that many HAM receivers do not reproduce 120 Hz well. When we started the earphones were connected between the plate of the AF amplifier and the 90
/archives//html/Amps/2012-05/msg00248.html (9,096 bytes)

13. Re: [Amps] ferroresonant power supplies (score: 1)
Author: Ron Youvan <ka4inm@gmail.com>
Date: Thu, 10 May 2012 20:25:04 -0400
Danny NG9R Pease: EG&G tower lights (strobes) have 1,000 Volt ferroresonant power supplies, self regulation is a FAA requirement. -- 73 Ron KA4INM - All E-mail sent to this address shall linger in th
/archives//html/Amps/2012-05/msg00257.html (7,477 bytes)

14. Re: [Amps] The power of an over sized electrolytic capacitor / how much PS filter C is enough? (score: 1)
Author: Ron Youvan <ka4inm@gmail.com>
Date: Thu, 10 May 2012 20:43:54 -0400
/*snip*/ We also need to take into account the fact that many HAM receivers do not reproduce 120 Hz well. When we started the earphones were connected between the plate of the AF amplifier and the 90
/archives//html/Amps/2012-05/msg00258.html (9,311 bytes)

15. Re: [Amps] filament instant heating query / simple remedy (score: 1)
Author: Ron Youvan <ka4inm@gmail.com>
Date: Sat, 16 Jun 2012 11:57:45 -0400
Most commercial broadcast transmitters monitor the current through tube filaments and possibly the Voltage. The current is much better because it can't be wrong at the tube like the Voltage can. As c
/archives//html/Amps/2012-06/msg00209.html (9,114 bytes)

16. Re: [Amps] Acoustic Noise Comparison (score: 1)
Author: Ron Youvan <ka4inm@gmail.com>
Date: Thu, 21 Jun 2012 22:08:19 -0400
I have never worked with MDF, but I think it is a wood product (or a plastic product) and an old rule for power amp construction is: never use a combustible material anywhere near the action. I have
/archives//html/Amps/2012-06/msg00367.html (10,327 bytes)

17. [Amps] Fwd: Re: Oscilloscope Purchase (score: 1)
Author: Ron Youvan <ka4inm@gmail.com>
Date: Wed, 27 Jun 2012 08:39:04 -0400
That is because the 465 (I have one) was USABLE to 100 MHz, but FLAT to 60 MHz. So not being flat to 100 is no surprise. They were sold concurrently. I also have a 475A which is flat to 350 MHz, whic
/archives//html/Amps/2012-06/msg00420.html (7,543 bytes)

18. Re: [Amps] Oscilloscope Purchase (score: 1)
Author: Ron Youvan <ka4inm@gmail.com>
Date: Wed, 27 Jun 2012 12:53:59 -0400
All scopes of all brands with sufficient bandwidth (HF response) will work, but almost everything other than HP, Tek, R&S exhibit excessive vertical amplifier DC drift (the trace moves up and down as
/archives//html/Amps/2012-06/msg00425.html (9,082 bytes)

19. Re: [Amps] How lossy is Nylon at 50 MHz? (score: 1)
Author: Ron Youvan <ka4inm@gmail.com>
Date: Sat, 07 Jul 2012 16:20:00 -0400
All nylon has rather poor weather resistance, even the UV resistant flavors. Use "delrin" if at all possible instead. -- 73 Ron KA4INM - All E-mail sent to this address shall linger in the Google clo
/archives//html/Amps/2012-07/msg00106.html (8,682 bytes)

20. Re: [Amps] Neon xfmr for HiPot (score: 1)
Author: Ron Youvan <ka4inm@gmail.com>
Date: Mon, 16 Jul 2012 08:24:56 -0400
Yes, and you can have two diodes one in each direction for twice the Voltage for insulation testing. -- Ron - KA4INM _______________________________________________ Amps mailing list Amps@contesting.
/archives//html/Amps/2012-07/msg00202.html (7,726 bytes)


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