Search String: Display: Description: Sort:

Results:

References: [ +from:ToddRoberts2001@aol.com: 90 ]

Total 90 documents matching your query.

61. Re: [Amps] Tranformer Suppliers (score: 1)
Author: ToddRoberts2001@aol.com
Date: Sat, 8 Dec 2007 16:24:15 EST
I found these listings in AF4K's Ham Radio Repair pages : Heyboer Transformer Inc. 17382 Hayes Grand Haven, MI 49417 Phone: 616-842-5830 E-mail: heyboertransform@novagate.net They have rewound severa
/archives//html/Amps/2007-12/msg00082.html (7,498 bytes)

62. Re: [Amps] Vacuum Variable Fatigue Failures (score: 1)
Author: ToddRoberts2001@aol.com
Date: Sat, 16 Feb 2008 16:01:09 EST
I was looking closely at the mechanical marvel that is a Jennings Vacuum variable capacitor. I am wondering about whether the copper bellows arrangement that allows extension and contraction of the "
/archives//html/Amps/2008-02/msg00106.html (7,031 bytes)

63. Re: [Amps] Class-E Amplifiers (score: 1)
Author: ToddRoberts2001@aol.com
Date: Fri, 29 Feb 2008 13:24:14 EST
In a message dated 2/29/2008 10:14:29 A.M. Eastern Standard Time, wlfuqu00@uky.edu writes: Class E amplifiers have high efficiency but what about gain and drive power. Some that I have see have about
/archives//html/Amps/2008-02/msg00220.html (8,169 bytes)

64. Re: [Amps] Class-E Amplifiers (score: 1)
Author: ToddRoberts2001@aol.com
Date: Fri, 29 Feb 2008 16:05:05 EST
In a message dated 2/29/2008 3:04:05 P.M. Eastern Standard Time, wlfuqu00@uky.edu writes: You can't simply tune out the capacitance with inductance and say you have no power loss on the input of the
/archives//html/Amps/2008-02/msg00225.html (8,099 bytes)

65. Re: [Amps] 1/4" shaft connectors (score: 1)
Author: ToddRoberts2001@aol.com
Date: Fri, 26 Sep 2008 21:14:39 EDT
Hil, Surplus Sales of Nebraska has 1/4 x 1/4 shaft couplers for $4 each, $3.50 each 3 or more or $3.25 each for 20 or more. 73 Todd WD4NGG **Looking for simple solutions to your real-life financial c
/archives//html/Amps/2008-09/msg00220.html (8,259 bytes)

66. Re: [Amps] caps across rectifier diodes (score: 1)
Author: ToddRoberts2001@aol.com
Date: Tue, 3 Mar 2009 11:52:57 EST
Back when I first started building some low power transmitters I always seemed to notice a slight hum or buzz superimposed on the carrier until I bypassed the power supply diodes with .01 caps across
/archives//html/Amps/2009-03/msg00102.html (8,734 bytes)

67. Re: [Amps] Microwave Transformers? (score: 1)
Author: ToddRoberts2001@aol.com
Date: Wed, 11 Mar 2009 12:12:26 EDT
A lot have quite high resistance windings for the power rating, so will give poor regulation and run hot on continuous load. Most also have too few turns on the primary for continuous energisation, a
/archives//html/Amps/2009-03/msg00310.html (9,867 bytes)

68. Re: [Amps] Silver plating (score: 1)
Author: ToddRoberts2001@aol.com
Date: Sat, 11 Apr 2009 05:31:59 EDT
Hi All, Very interesting info on silver plating an HF tank coil, thanks. From all I have read it sounds like silver plating a tank coil is nice for aesthetic reasons but does little if any to improve
/archives//html/Amps/2009-04/msg00129.html (8,996 bytes)

69. Re: [Amps] filament transformers (score: 1)
Author: ToddRoberts2001@aol.com
Date: Sat, 16 May 2009 10:29:45 EDT
What has happened to "roll your own" custom filament transformers? I have never purchased a commercially made filament transformer after building more than 40 amplifiers over 25 years....I still roll
/archives//html/Amps/2009-05/msg00085.html (10,579 bytes)

70. Re: [Amps] HV switch-mode power supply (score: 1)
Author: ToddRoberts2001@aol.com
Date: Sat, 23 May 2009 13:28:33 EDT
That is impressive, but IMO, it needs to be done by the utilities, not by each homeowner. Barring some technological breakthrough, they have an economy of scale that we individuals can not match at p
/archives//html/Amps/2009-05/msg00173.html (8,816 bytes)

71. Re: [Amps] Cleaning Cigarette tar....? (score: 1)
Author: ToddRoberts2001@aol.com
Date: Fri, 31 Jul 2009 19:27:57 EDT
Picked up an amp the looks like its been around smokers.....Any thoughts on best way to try and clean up most of the tar / residue? Thanks... Rich N7TR _______________________________________________
/archives//html/Amps/2009-07/msg00452.html (8,281 bytes)

72. Re: [Amps] SGC-Mini Lini (score: 1)
Author: ToddRoberts2001@aol.com
Date: Sun, 9 Aug 2009 22:54:16 EDT
Does anyone out there actually own a Mini Lini? 73 Bill wa4lav ______________________________________________________________ I don't think SGC ever actually produced any of the Mini-Linis for sale.
/archives//html/Amps/2009-08/msg00191.html (7,121 bytes)

73. [Amps] QEX Article on EER (score: 1)
Author: ToddRoberts2001@aol.com
Date: Sat, 22 Aug 2009 14:16:40 EDT
Hi All, Wanted to pass along there was an interesting article in the new Sept-Oct issue of QEX magazine by Mike Hamel, WO1U called Phase Controlled Differential Drive for EER Amplifiers. He came up w
/archives//html/Amps/2009-08/msg00383.html (6,703 bytes)

74. Re: [Amps] Silver Plating Tank Coil ?? (score: 1)
Author: ToddRoberts2001@aol.com
Date: Sun, 20 Sep 2009 00:10:03 EDT
Hi All, If the main goal is to prevent tarnish on a tank coil and keep it looking nice, wouldn't gold plating be the best to use? Even silver will become blackened with tarnish after a few years out
/archives//html/Amps/2009-09/msg00250.html (7,972 bytes)

75. Re: [Amps] Silver Plating Tank Coil ?? (score: 1)
Author: ToddRoberts2001@aol.com
Date: Sun, 20 Sep 2009 04:42:07 EDT
Hi All, Thanks for the comments on Gold plating a tank coil. I think one thing that was overlooked is Gold plating is usually extremely thin, on the order of 1 or 2 microns, or 0.04 to 0.08 mil. At H
/archives//html/Amps/2009-09/msg00254.html (7,762 bytes)

76. Re: [Amps] Vernier knobs? (score: 1)
Author: ToddRoberts2001@aol.com
Date: Sat, 3 Oct 2009 14:27:22 EDT
It sounds like for what you are looking for you will have to make something up from parts. A vernier knob turns counter with a center knob marked with perhaps a degree wheel to count the increments o
/archives//html/Amps/2009-10/msg00047.html (7,270 bytes)

77. Re: [Amps] PTFE dielectricum variable cap (score: 1)
Author: ToddRoberts2001@aol.com
Date: Mon, 15 Mar 2010 18:33:11 EDT
Hi, I would like to get the opinion of this group on constructing a homemade variable 500 pF/1nF capacitor for my new 160mtrs amp. To get sizes down I am considering using 1mm (40 mill) thick teflon
/archives//html/Amps/2010-03/msg00282.html (9,236 bytes)

78. Re: [Amps] PTFE dielectricum variable cap (score: 1)
Author: ToddRoberts2001@aol.com
Date: Mon, 15 Mar 2010 20:19:49 EDT
Teflon is rated for 1500 kv per inch. .040 thickness is good for 60,000 volts! You can find the info at google "teflon voltage". A typical application is for a plate bypass at VHF or UHF where 5 to 1
/archives//html/Amps/2010-03/msg00288.html (9,512 bytes)

79. Re: [Amps] Teflon Caps (score: 1)
Author: ToddRoberts2001@aol.com
Date: Wed, 17 Mar 2010 13:28:11 EDT
Tesla Coil builder sites are good places to read about different builder's experiences with high voltage caps. Their advice is to limit the voltage across each capacitor to no more than 5KV. Many of
/archives//html/Amps/2010-03/msg00346.html (7,934 bytes)

80. Re: [Amps] Cleaning air-wound coils (score: 1)
Author: ToddRoberts2001@aol.com
Date: Wed, 5 May 2010 20:23:57 EDT
Based on everthing presented in this thread, then, at HF would a *very* thin layer of plated gold decrease performance in any significant way? If not, that might be a long-term method to keep things
/archives//html/Amps/2010-05/msg00065.html (8,823 bytes)


This search system is powered by Namazu