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## [Towertalk] Tailtwister won't turn.

 To: [Towertalk] Tailtwister won't turn. k2av@contesting.com (Guy Olinger, K2AV) Mon, 5 Aug 2002 23:54:09 -0400
 ```Can't seem to find it at the moment, but seem to remember something like the following gut speculation.... Two electrolytic caps of equal value connected like terminals in series will act as an AC capacitor of one half the value, because: Since one electrolytic cap by itself will conduct a dc voltage one way, I think the combination would quickly develop a charge, as in electrons check in (because both caps only conduct DC one way, an ersatz diode) and they don't check out (because BOTH DON'T conduct the other way). Model it by placing a diode across a regular capacitor of the same value (in parallel). Do the same for 2nd identical regular capacitor. Now connect the two combo's with both diode anodes together. Electrons check in but they can't check out. This bias would match 1/2 the peak-to-peak voltage of the AC, and quickly, as mostly in the first quarter cycle starting either direction. This would have the effect of "biasing" BOTH caps with a DC voltage to the point where no DC current flowed, making it REALLY two caps in series This would also mean that BOTH caps have to be DC rated by at least the AC peak to peak. No splitting of the voltage drop. In either direction at peak you have the sum of the bias and the AC together across one cap (AC p-p) and the AC minus the bias (zero) across the other cap. You should be able to measure this bias after you take the AC off for a bit if the Caps aren't real leaky. If the positive terminals are connected together, the bias will be positive relative the outside terminals. Will keep looking, or maybe this will stir someone's memory. 73, Guy. ----- Original Message ----- From: To: Sent: Monday, August 05, 2002 3:23 PM Subject: Re: [Towertalk] Tailtwister won't turn. > The recommended / described use of electrolytic capacitors > for replacing an AC motor start capacitor is a SERIES connection > so the effective capacitance is HALF (unless the reverse biased > side acts as a short on each half cycle...then the effective capacitance > would be equal to the marked value...anybody know?). > > Tom N4KG > > On Mon, 5 Aug 2002 "Mike & Coreen Smith" writes: > > Yes, you can stick two electrolytics together like that. > > Remember that the value will double if you parallel 2 identical caps > > together like that. > > > > GL > > > > Mike-VE9AA > > ----- Original Message ----- > > From: "Dale L Martin" > > To: > > Sent: Monday, August 05, 2002 12:49 PM > > Subject: RE: [Towertalk] Tailtwister won't turn. > > > > > > > > > I heard/read/dreamed/made up somewhere that, in the absence of a > > replacement > > > motor starting capacitor, a TEMPORARY motor starting capacitor > > substitution > > > (for testing purposes only) can be made by putting two > > electrolytic > > > capacitors of about 250Ufd/100VDC back to back (plus-neg-neg-plus? > > > neg-plus-plus-neg?) to see if it is indeed the motor starting > > capacitor that is the problem. > > > > > > Does that actually work? > > > > > > 73, > > > dale, kg5u > > > > > > ________________________________________________________________ > GET INTERNET ACCESS FROM JUNO! > Juno offers FREE or PREMIUM Internet access for less! > Join Juno today! For your FREE software, visit: > http://dl.www.juno.com/get/web/. > _______________________________________________ > Self Supporting Towers, Wireless Weather Stations, see web site: http://www.mscomputer.com > Call 888-333-9041 to place your order, mention you saw this ad and take an additional 5 percent off > any weather station price. > _______________________________________________ > Towertalk mailing list > Towertalk@contesting.com > http://lists.contesting.com/mailman/listinfo/towertalk > ```
 Current Thread [Towertalk] Tailtwister won't turn., (continued) [Towertalk] Tailtwister won't turn., W0UN--John Brosnahan [Towertalk] Tailtwister won't turn., Chris BONDE [Towertalk] Tailtwister won't turn., Mark [Towertalk] Tailtwister won't turn., Mark [Towertalk] Tailtwister won't turn., W0UN--John Brosnahan [Towertalk] Tailtwister won't turn., Steve Katz [Towertalk] Tailtwister won't turn., Dale L Martin [Towertalk] Tailtwister won't turn., Mike Gilmer, N2MG [Towertalk] Tailtwister won't turn., n4kg@juno.com [Towertalk] Tailtwister won't turn., Don Hall [Towertalk] Tailtwister won't turn., Guy Olinger, K2AV <= [Towertalk] Tailtwister won't turn., Steve Katz [Towertalk] Tailtwister won't turn., Jim Smith [Towertalk] Tailtwister won't turn., Mike Gilmer, N2MG [Towertalk] Tailtwister won't turn., Steve Katz [Towertalk] Tailtwister won't turn., Bill Coleman