[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

*To*: tesla-at-pupman-dot-com*Subject*: Re: vac tube TC secondary design question*From*: Esondrmn-at-aol-dot-com (by way of Terry Fritz <twftesla-at-uswest-dot-net>)*Date*: Thu, 08 Jun 2000 16:44:46 -0600*Approved*: twftesla-at-uswest-dot-net*Delivered-To*: fixup-tesla-at-pupman-dot-com-at-fixme

In a message dated 6/6/00 4:54:35 PM Pacific Daylight Time, tesla-at-pupman-dot-com writes: << Hi coilers, I want to design a good secondary for my tube coil. My primary is 9" diameter and 5" high. The LC of the primary circuit resonates at 650kHz. I cannot really change this much - in particular I cant make it much lower. I believe the problem is to design a secondary that resonates at this frequency, has the highest number of turns and has the largest diameter possible so that the coupling is high. I was thinking of between 5" and 6" diameter, but this is difficult without building numerous prototypes. Has anyone wound a secondary that resonates at around 650kHz? What were the dimensions? Is there a good way of estimating the resonant frequency of the secondary without building it? I tried using the formula f (MHz)= (1175 * (h/d)^0.2)/(d*N) but it always overestimates the frequency when I build and test coils. Do you think it is more important to have a higher number of turns, or a higher coupling factor for a tube coil? I was thinking of using 16" length of #18 on 5" diameter, approx 380 turns. Does this seem about right? Simon BTW: My tube coil now uses a pair of 572Bs, a 4kv supply, one huge 1nF 15KV doorknob primary C, and a 16 turn copper tube primary L. >> Simon, I ran some numbers on your specs. Using #18 wire, 5" dia and 16" winding length will yield an unloaded frequency of 803 khz. It would be 536 khz with a 10 pf topload and 656 khz with a 4 pf topload. Ed Sonderman

- Prev by Date:
**Re: ignition coil for high voltage source** - Next by Date:
**RE: ignition coil for high voltage source** - Prev by thread:
**Re: vac tube TC secondary design question** - Next by thread:
**dc rotary motor** - Index(es):