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In article ,
Bob Miller wrote: For balanced line, it has a "broadband toroidal transformer" according to the review in a 1980 QST. When I place a VOM multi-meter across the two balanced line terminals, it shows continuity. Is that normal, or is the balun cooked or shorted? Very probably normal... or, at least, to be expected of many types of balun and thus not diagnostic of a failure. You're probably reading the DC resistance one or more of the windings, which would be rather less than an ohm. Based on what I see in Sevick's book on baluns and ununs, both the Guanella 4:1 current balun and the various Ruthroff voltage balun configurations would exhibit this behavior. A Guanella 1:1 with the center of the load un-grounded would not, nor would a Reisert or W2DU 1:1 balun. Now, for something completely different. If you want to revisit an old controversy, and if you're not adverse to modifying a classic piece of equipment, you might want to review the various debates about the pros and cons of the Ultimate Transmatch vs. the SPC configuration. See if you can locate a copy of the August 1981 QST, and review the Technical Correspondence column on pages 42-43. As I understand it, the SPC configuration can be shown to have some significant technical advantages over the Ultimate Transmatch, in terms of matching range and harmonic attenuation, when the same component values are used in each. It is reportedly possible to re-wire an Ultimate into an SPC configuration little or no cost, as both use a split-stator capacitor (just in different places in the circuit). -- Dave Platt AE6EO Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
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On Sat, 4 Jun 2005 14:01:25 -0700, "John Smith"
wrote: Bob: If you don't mind me asking--how much did you pay for it, I have one in the barn here I bought as lot with other gear from an estate sale--just wondering... John The eBay bidding started at $100. There were 20 bids, and it finally ended up at $171, plus $20 for shipping. The case is a little scratched up, but the front panel and inside components look good. Bob k5qwg |
#5
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WOW, that makes me smile... I am going to dig it out!
Warmest regards, John "Bob Miller" wrote in message ... On Sat, 4 Jun 2005 14:01:25 -0700, "John Smith" wrote: Bob: If you don't mind me asking--how much did you pay for it, I have one in the barn here I bought as lot with other gear from an estate sale--just wondering... John The eBay bidding started at $100. There were 20 bids, and it finally ended up at $171, plus $20 for shipping. The case is a little scratched up, but the front panel and inside components look good. Bob k5qwg |
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