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91
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eHam Forums / Misc / RE: RF Voltmeter
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on: April 15, 2012, 11:46:59 PM
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There's nothing cheaper than making a homemade RF probe for your own voltmeter; a simple diode and a 0.1uF disc capacitor. Your voltmeter will show peak RF voltage, minus the diode's voltage drop, but that can be converted to RMS volts by multiplying by 0.707. GL
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93
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eHam Forums / Misc / RE: David Clark Head set
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on: April 06, 2012, 07:26:24 AM
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Bob Heil specializes in ham gear; David Clark specializes in aviation stuff. That having been said, many hams have used or are using Clark headsets with their ham equipment, and probably with good personal reasons. I can see where they could come in handy at contest stations or during Field Day, but I find them somewhat uncomfortable for casual use in the shack. Heck, I didn't care for them that much when I was flying--but that's me. Your results may vary. GL
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94
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eHam Forums / HomeBrew / RE: Ernie wanted
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on: April 05, 2012, 11:56:22 PM
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A couple of ideas. First, ham helpers are Elmers, not Ernies. Second, look to the electronics courses at your local colleges and vocational schools, and talk with the counselors or, better yet, the instructors, and tell them what you are interested in and ask their recommendations. Your local library may have several books on electronics projects. If not, go online to the ARRL.org bookstore and get a Communications Handbook. It will cover virtually everything you need to know about radio communications and construction techniques, and includes building projects that include transmitters, receivers, power supplies, antennas, test equipment, etc. Theory is included, too, as are operating procedures, safety considerations, component datasheets, etc. It's well worth the money, and even an older handbook will teach you a lot. Of course, the bookstore has many other great theory and construction books as well. There are some good online sources, too. Google around for "online electronics course, "online communications course," etc. The Navy has a really good one online. You might also find some useful information in some of the YouTube videos (and some not-so-useful information as well). Another good source for construction ideas, although not necessarily ham radio, are the Make Magazine blog at makezine.com, and the do-it-yourself projects at www.instructables.comOne great online source for beginners is the "Elmers 101" course, which teaches the theory and construction of the nice, and inexpensive, SW40 CW transceiver. Take a look at the lessons at http://www.qsl.net/kf4trd/faq.html to see what it covers. You will also find a lot of good construction technique, projects to work on, and other tidbits from the the QRP Amateur Radio Club International and its quarterly magazine. See the web site at http://www.qrparci.org/Finally, use one of the online ham search programs that allows searching by city or zip code (e.g. ARRL's http://www.arrl.org/advanced-call-sign-search), then call some of the hams who are listed, and find out if there's a place they like to meet, or a club they are members of. I found 18 listings for your town alone, but a nearby larger town might have a larger listing. One of them might want to volunteer to be your Elmer, or put you in touch with someone who will.
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95
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eHam Forums / Misc / RE: QRZ Forums Down??
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on: April 05, 2012, 09:08:14 AM
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Once, when it was raining hard, someone asked Will Rogers if he thought it would ever stop. He replied, "It always has before." I'm virtually certain the forums will open up soon... 
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96
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eHam Forums / Elmers / RE: Upgrading to General Class
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on: April 05, 2012, 09:04:14 AM
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Yes, upgrade. You never know when you'll have the opportunity to pick up an HF rig, or even operate a Field Day station. What if an affordable rig shows up in a yard sale next month? It would be nice to use all its capabilities, not just its 10m SSB, wouldn't it?
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97
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eHam Forums / HomeBrew / RE: 40.08 MHz Crystals
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on: March 31, 2012, 05:16:06 AM
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From its web site, "ICM custom quartz crystals typically have frequency ranges of 32.768 KHz to 200 MHz. If your application requires higher frequencies, please contact our crystal engineers at 1-800-725-1426." www.icmfg.com
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98
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eHam Forums / HomeBrew / RE: Butane Soldering irons, like Portasol?
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on: March 20, 2012, 01:16:20 PM
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They tell us that leaded gasoline (tetraethyl lead) would ruin catalytic converters in cars--the lead contaminates the platinum in them. Could you have gotten a little solder splatter onto your iron's catalytic element? Just a thought....
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100
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eHam Forums / Misc / RE: Hams in Helotes, Texas
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on: March 17, 2012, 11:16:16 AM
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There are apparently 60 or so there in Helotes. Try using the callsign lookup at www.arrl.org, and enter W5GMT, or even a dummy call sign. Either it will find it or not, but it will give you a chance to search for call signs in any city or zip code area. My quick search showed 68 entries for Helotes, but I'm sure some are duplicates, some have moved, and some are now inactive. GL
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102
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eHam Forums / Elmers / RE: High SWR after replacing coax
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on: March 17, 2012, 11:02:53 AM
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Put a 50Ω non-inductive dummy resistor on the antenna end of the coax and report what kind of SWR you see. If the coax and connectors are alright, it should be 1:1. If not, then I'd suspect a bad connector fitting.
Another thing, really lossy cable can 'improve" SWR a lot, but doesn't do anything to help get the signal to the antenna. Is your SWR equally poor across the band with your new cable, or does it seem to be better at one end rather than the other? If it's the latter, then you may want to retrim the antenna. GL
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103
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eHam Forums / Elmers / RE: Dare I ask, Who does CB alignment
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on: March 14, 2012, 12:46:48 PM
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Crystal aging could be causing the problem, but a few kc's is a lot!
Depending on where you live, a local truck stop might host a competent CB repair shop. But before using it, I would ask several truckers for their impressions and ratings on the work done there. Then keep your fingers crossed.
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