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Lprimary tuning calculation

Original poster: Terry Fritz <laptop@xxxxxxxxxxxxxxxxxxxxxxx>

Hi All,

We know that the primary system needs to be tuned about 5% lower than the secondary due to streamer loading. While playing with ScanTesla, I realized that the streamer loading and how it affects tuning is fairly straight forward. A very good estimate (1%) of tuned Lprimary inductance is:

Lp = Ls x (Cs + Ca) / Cp

	Lp = Primary coil inductance
	Ls = Secondary coil inductance
	Cs = Secondary capacitance
	Ca = Arc capacitance = 1pF / foot of streamer
	Cp = Primary capacitance
Almost all of the secondary frequency drop is due to the capacitance of the streamer and the 220k part of the streamer load is fairly insignificant. Thus we can simply add 1pF/foot of capacitance to Csecondary for the calculation.