While reading up on tungsten filament life, I came across this interesting article. This was written for ordinary lamps with tungsten filaments but I imagine the recommendations may be applicable for
This brings to mind another question I have always wanted to ask, and I believe that it is on-topic when we start talking about DC on 3-500Z tube filaments. If you power your filament with DC, wouldn
73 Peter G3RZP I don't think it is possible to make a Class E amplifier linear in the way that a Class AB amplifier is linear. One practical way to use a Class E amplifier to amplify SSB is to config
Tomm KD7QAE Fiberglass tubing is good material to wind an anode choke over. 73 Todd WD4NGG _______________________________________________ Amps mailing list Amps@contesting.com http://lists.contestin
United States Plastic Corp. ( www.usplastic.com ) has a very good selection of plastics that we would be interested in for high-power RF circuits. They have phenolic rods - tubing - sheets Grade XX u
Here are some nice pictures of the aspidistra transmitter. It was made by RCA for WJZ in New Jersey but the FCC would not allow use of a 600 kw transmitter in the US AM BCBand which had a top power l
U.S. Marine Corps awards $75 million contract for AN/PRC-150 (C) high-frequency radios Apr 26, 2005 4:12 PM I have a Harris RF-590 receiver and last summer I had sent it to Harris for service. I had
I like to find a circuit of a 50 volts 20amps power supply...can any one help.. many thanks joe 9H1GT Joe Francalanza Don't forget that with a few simple precautions you can wire several 13.8VDC regu
Greetings, has anyone else seen the new SGC Mini Lini 500 watt output Linear Amplifier using Class-E Technology and Envelope Elimination and Restoration to amplify an SSB signal with 90% efficiency?
Your statement puzzles me. A house powered by AC mains of about 1 kHz or higher is shockproof. The human nervous system does not respond to frequencies that high or higher. I realize someone could co
I wonder if anyone else has seen the article in the July/August 2006 QEX on the combination Class AB1/F linear amp using EER ? He drives the grids in Class AB1 at low levels and when drive increases
I can understand why ranges, heaters, AMPLIFIERS and other high power devices need a 240V supply, and I can understand why in North America that supply is balanced around neutral. What I don't unders
73 Bill wa4lav SGC states in their website that they ran into connectivity problems with the plug-in amplifier modules for the different bands for the Mini-Lini. They said the plug-in connectors were
In a message dated 7/7/2006 8:20:14 PM Eastern Standard Time, k5and@austin.rr.com writes: The tubes used were PL509 or PL519; the article interchanges both numbers, so go take your choice. The switch
In a message dated 7/9/2006 8:57:13 AM Eastern Standard Time, jbigham2@kc.rr.com writes: I have never used one of these, what do you do? Hook it up to the item to be checked and begin increasing the
In a message dated 8/11/2006 1:25:35 PM Eastern Standard Time, ke6cvh@yahoo.com writes: I was wondering if there is a "next size larger tubing" that will fit over it like telescoping aluminum tubing
One way I have done it is to make my own AC panel voltmeter using a low ac ma range meter and variable resistor and calibrate it with a good quality AC RMS DVM like a Fluke. Likewise you can check th
Start with the 1500 watt peak output amplifier described in the old APT application note, APT9701, which posits 25¢/watt for a Class C amplifier section with 70% efficiency at 27 MHz (ISM band,
In a message dated 11/20/2007 4:23:05 PM Eastern Standard Time, K7FL@arrl.net writes: I need to construct a 35uH air inductor using .250 copper tubing. D is around 5"; L = 10 inches. I can play with
In a message dated 12/7/2007 6:05:15 PM Eastern Standard Time, sccook1@cox.net writes: Where can an individual purchase core material, paper, wire, etc? We may need to get serious about winding our o