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so if i have a stock tesoro coil with an rx inductance of 6.95 and a tx of 6.45 or so because i have to mesure at the connector end what caps and resistors would work to use it on my tesoro like king cobra or should it just work
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Just change the caps in this picture. Set TX to a frequency you like and RX to
1.5 khz more by using a calculator like this one;http://www.siversima.com/rf-calculat...FfB3cAodsAgAzg
(put inductance and Capacitance to find frequency)
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ok after checking I found to have to change tx to 200n from 22n and rx to 150n from 15n does that sound right or is something that I am doing wrong.Comment
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and befor changing caps would the rx if not wired right as in the end and start backwards cause it to not ground balance out ferrite and have low detection on everything but ferro magnetic items. or is a cap change what i need anyone?Comment
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Hello calebsone,
I'm no expert, and some may say this is possibly not the right way,
But,
I recently built Carl and george's raptor,
The way I did it was :
Change TX capacitors to get the right TX frequency you require,
Then,
Leave alone,
Job done.
Start with basic suggested value of RX capacitors,
And check on scope,
Try to get a good shape of sine wave,
No funny slopes.
Then "peak out" the RX for highest amplitude by
Either adding 1nf capacitors one by one,
Or,
Lowering by using 2 smaller capacitors and working
Back up.
IE: if the starting point of 33nf is to high for your coil,
then Use 2 x 15nf and work back up.
I ended up fine tuning using 0.75nf 's
And was quite happy with the results.
Wildly changing caps from 100nf to 10nf
May get you there by chance,
Eventually.
Hopes this has helped.Comment
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