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References: [ +from:AVILASECA@BLUEWIN.CH: 72 ]

Total 72 documents matching your query.

41. Re: [Amps] current in primary of microwave oven transformer (score: 1)
Author: Angel Vilaseca <avilaseca@bluewin.ch>
Date: Mon, 28 Apr 2008 14:04:15 +0200
An interesting explanation of how a MOT compares with other transformers. Thanks Manfred! I guess that microwave oven transformers designers also try to use as little copper as possible, because of i
/archives//html/Amps/2008-04/msg00306.html (14,686 bytes)

42. Re: [Amps] current in primary of microwave oven transformer (score: 1)
Author: Angel Vilaseca <avilaseca@bluewin.ch>
Date: Tue, 29 Apr 2008 13:18:01 +0200
Again a crystal clear explanation. Thanks again Manfred! So I guess the only remaining option will be to remove the heating winding which is located between the primary and the secondary and replace
/archives//html/Amps/2008-04/msg00319.html (16,078 bytes)

43. Re: [Amps] Transformer heating (problem?) (score: 1)
Author: Angel Vilaseca <avilaseca@bluewin.ch>
Date: Thu, 12 Feb 2009 08:32:39 +0100
I observed the same phenomenon with microwave oven transformers. The core gets very hot when power is applied to the primary even for a few minutes, even with no load on the secondary. This is becaus
/archives//html/Amps/2009-02/msg00356.html (10,567 bytes)

44. [Amps] Sweep tube amp by DL9AH, made by HB9AWI (score: 1)
Author: Angel Vilaseca <avilaseca@bluewin.ch>
Date: Fri, 26 Jun 2009 22:28:51 +0200
Gentlemen, I just bought an old amp that uses 5 PL 519 TV sweep tubes in parallel. As it reads on the box, it was home made on June 1983 by HB9 AWI. The amp does not work anymore, but it is superbly
/archives//html/Amps/2009-06/msg00123.html (8,737 bytes)

45. Re: [Amps] Sweep tube amp by DL9AH, made by HB9AWI (score: 1)
Author: Angel Vilaseca <avilaseca@bluewin.ch>
Date: Mon, 29 Jun 2009 11:26:01 +0200
Dear Felipe, What a coincidence! I just got this quarter-century old amp with obsolete tubes, and almost at the same time, the CQ DL publies an article about a similar design! About the Fuchskreis: T
/archives//html/Amps/2009-06/msg00140.html (13,333 bytes)

46. Re: [Amps] Sweep tube amp by DL9AH, made by HB9AWI (score: 1)
Author: Angel Vilaseca <avilaseca@bluewin.ch>
Date: Tue, 30 Jun 2009 08:58:42 +0200
A very good point Bill! In this particular amp, plenty of room is available for the tank circuit. I will consider replacing the "Fuchskreis" with a Pi or PI-L circuit. But then there is the problem o
/archives//html/Amps/2009-06/msg00147.html (10,803 bytes)

47. Re: [Amps] Sweep tube amp by DL9AH, made by HB9AWI (score: 1)
Author: Angel Vilaseca <avilaseca@bluewin.ch>
Date: Tue, 30 Jun 2009 09:10:05 +0200
Hi Alex, An interesting idea, but since there is plenty of room in the tank circuit compartment of the amp, I think I will first try replacing the Fuchskreis with a pi-circuit, if the anode impedance
/archives//html/Amps/2009-06/msg00148.html (11,916 bytes)

48. Re: [Amps] Sweep tube amp by DL9AH, made by HB9AWI (score: 1)
Author: Angel Vilaseca <avilaseca@bluewin.ch>
Date: Wed, 01 Jul 2009 13:47:44 +0200
Yes, to obtain tha beautiful cherry red glow of the plates :-) a better option would be to increase the plate voltage. With only 600 V from plate to cathode, the cathode current gets too high and the
/archives//html/Amps/2009-07/msg00007.html (8,671 bytes)

49. Re: [Amps] Sweep tube amp by DL9AH, made by HB9AWI (score: 1)
Author: Angel Vilaseca <avilaseca@bluewin.ch>
Date: Wed, 01 Jul 2009 14:43:59 +0200
I see. A sort of push-pull oscillator with the link between the plate of two tubes acting as an inductance. Therefore you try to keep this inductance low by using sheet metal instead of wire. Resonan
/archives//html/Amps/2009-07/msg00008.html (14,490 bytes)

50. Re: [Amps] Sweep tube amp by DL9AH, made by HB9AWI (score: 1)
Author: Angel Vilaseca <avilaseca@bluewin.ch>
Date: Wed, 01 Jul 2009 14:48:29 +0200
Kudos to CQ-DL! I e-mailed them yesterday to buy a copy of the May 2009 issue of CQ-DL Magazine . Instead I found this morning in my mailbox an e-mail with a pdf of the article - no charge! Many than
/archives//html/Amps/2009-07/msg00009.html (11,038 bytes)

51. Re: [Amps] Sweep tube amp (score: 1)
Author: Angel Vilaseca <avilaseca@bluewin.ch>
Date: Fri, 03 Jul 2009 11:37:05 +0200
Dennis, Nice idea to write a book about this subject. What could be more in the ham spirit than to squeeze some industrial surplus (tubes and other things) into ham service? In a TV set, the line out
/archives//html/Amps/2009-07/msg00076.html (8,884 bytes)

52. [Amps] inexpensive HV fuse (score: 1)
Author: Angel Vilaseca <avilaseca@bluewin.ch>
Date: Wed, 22 Jul 2009 08:20:51 +0200
Commercially available HV fuses are quite expensive. I thought of using a small spring instead, like the ones in ball-point pens. They are about one inch long and could be spread between two isolated
/archives//html/Amps/2009-07/msg00272.html (9,700 bytes)

53. Re: [Amps] (Perhaps) A plate choke too far ... (score: 1)
Author: Angel Vilaseca <avilaseca@bluewin.ch>
Date: Thu, 14 Jan 2010 08:11:45 +0100
If avoiding saturation is the point, how about using a ferrite rod instead of a toroid? Or using a toroid but cutting a small gap into it (with an abrasive disc)? Angel Vilaseca HB9SLV Radio WC6W a é
/archives//html/Amps/2010-01/msg00173.html (8,924 bytes)

54. Re: [Amps] KK5DR's ferrite loaded (score: 1)
Author: Angel Vilaseca <avilaseca@bluewin.ch>
Date: Wed, 20 Jan 2010 18:27:06 +0100
Hi, Manfred, You explained why a plate choke wound on a ferrite rod won't be better than one wound on the usual ceramic rod. But on the other hand, a choke wound on a ferrite rod is used as the filam
/archives//html/Amps/2010-01/msg00263.html (8,401 bytes)

55. Re: [Amps] HV Fuses (score: 1)
Author: Angel Vilaseca <avilaseca@bluewin.ch>
Date: Wed, 17 Feb 2010 08:16:59 +0100
How about using a string of mains-voltage fuses in series? Has anybody tried this? After all, that is what we do for every component of our HV power supplies: capacitors, diodes, resistors... are all
/archives//html/Amps/2010-02/msg00462.html (9,432 bytes)

56. Re: [Amps] HV Fuses (score: 1)
Author: Angel Vilaseca <avilaseca@bluewin.ch>
Date: Wed, 17 Feb 2010 09:09:14 +0100
Just another idea... In the old car ignitions there was a capacitor in parallel between the points. This was made to avoid an arc between the points when the point were switching off 12 Volts into th
/archives//html/Amps/2010-02/msg00464.html (9,689 bytes)

57. [Amps] [Fwd: [Mw] K2RIW: N2UO Looking for a HV transformer.] (score: 1)
Author: Angel Vilaseca <avilaseca@bluewin.ch>
Date: Mon, 25 Oct 2010 13:19:53 +0200
_______________________________________________ Amps mailing list Amps@contesting.com http://lists.contesting.com/mailman/listinfo/amps
/archives//html/Amps/2010-10/msg00361.html (6,391 bytes)

58. Re: [Amps] Tube Cooling (score: 1)
Author: Angel Vilaseca <avilaseca@bluewin.ch>
Date: Fri, 26 Nov 2010 07:20:49 +0100
how about using a blower from a discarded microwave oven? Angel Vilaseca HB9SLV _______________________________________________ Amps mailing list Amps@contesting.com http://lists.contesting.com/mailm
/archives//html/Amps/2010-11/msg00466.html (7,736 bytes)

59. Re: [Amps] 4 X 4-400C or 4 X 3-500Z HF amplifier (score: 1)
Author: Angel Vilaseca <avilaseca@bluewin.ch>
Date: Wed, 15 Dec 2010 14:26:00 +0100
Hi, I bought a NOS 5CX1500A. I plan to use it in an HF amp. Sockets for this tube are rather scarce. Has someone tried to use it in a home-made fixture? I know, a tube is supposed to be used in the o
/archives//html/Amps/2010-12/msg00156.html (7,874 bytes)

60. Re: [Amps] 5CX1500 socket ( changed subject ) (score: 1)
Author: Angel Vilaseca <avilaseca@bluewin.ch>
Date: Fri, 17 Dec 2010 07:50:20 +0100
There is presently a new Eimac Y-770 / SK-810B Socket (Y770) for 4CX1000A+ for sale. Item 380079009063 I hope $ 699.99 is not the typical price for a SK-840 + SK-806 There's no hurry. I'll shop aroun
/archives//html/Amps/2010-12/msg00180.html (10,238 bytes)


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