[Lowfer] My variometer resistance

[Peter Barick]

Gents,

Hmm, I have another take ... some of the previous ones were good information in general, but let's take a look at Andy's application in particular.

!) Paul calculates the variometer has 88 turns. That's too much to deal with if the goal is to optimise an 1750M loading coil. The idea is to use the vari. to fine tune to resonance, not roam the LF landscape. So, a) get the main bucket to resonance slightly higher that the target freq. Then a bit more L is added with the vari. coil.

2) At all costs keep the amount of wire resistance to a Min. A) use a proper 2D:1L former. If needed, beef up the 5-Gal pale with Dia boosters, like home Ins., that pink stuff cut in strips and glued to the bucket. B) I reco a min of no. 14 enameled or house wire.

3) Keep the inter connections to a min., and when needed use good connection practices, ie, soldered lugs.

4) Silver coated, Teflon Ins. wire (turns can be tightly together using it) is available on Ebay. Price is right and won't have to buy in 500Ft rolls!
--Peter
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>>> Andy - KU4XR <ku4xr at yahoo.com> 10/24/08 2:46 PM >>>
Learning as I'm going, My variometer was the single best thing
I have done for my beacon so far, bringing the greatest gain.
It's a 5 gallon paint bucket, wound with very small wire. I'm 
not sure of the guage, maybe #28 to #30 ( 6 stranded solid 
burglar alarm wire ). I know small wire has higher resistance,
So I thought it would take fewer turns for a needed inductance.
I measure 9.0 OHMs DC resistance across the variometer, and I am
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