Need help with whites coil

[boficle]

Hello everyone, I recently purchased a whites 8" Concentric Prizm coil # 801-3221, I tried to check the Inductance and I don't like what I'm seeing, Does anybody know what the specs on this coil should be. Any help would be great... Thanks

[proscan]

The parameters should be (approx): R1=35 Ohm; L1=14mH and R2=1,7 Ohm, L2=2550uH.

Hope this helps.

Piotr

[homefire]

Whites have a cap and resister on the Tx side that messes up taking readings. I have a Prizm II I can give you the reading on if you need them.

[boficle]

Thanks proscan, My resistance are both same as yours but my Inductance are 13960 uH and 546 uH.

[boficle]

Thanks homefire, I would really like to get your readings to compare with mine.

[Dave J.]

In order to determine the inductance and capacitance separately you'll have to take the measurements at different frequencies and then apply the appropriate algebra. I don't think there are any resonating capacitors in the searchcoil but may be mistaken on that. If Prizm searchcoils are compatible with the MXT (someone here probably knows), then there wont be resonating caps in there.

The transmitter inductance is approximately 550 microHenries and the receiver inductance is approximately 14 milliHenries. The receiver resistance isn't important. the transmitter circuit DC resistance as measured through the connector does matter, and is somewhere in the vicinity of 2 1/2 ohms (someone here probably has a precise 4-wire ohmmeter measurement). I don't know what the capacitances are.

[homefire]

Measurements taken with WonderBar Chines Toy DIY M12864 Graphics Version Transistor Tester Kit LCR ESR PWM With Case
From BangGood ! Eaaa It works.

Prizm II stock coil in excellent working order.

Rx Pins 1 and 2 35.4 Ohms at 15.8mH

Tx Pin 4 and 5 1.7 Ohms at 550uH aka .550mH

Zero Connectivity between these pins. Open Capacitance only. Did not check Shield connectivity. Edit. Went back and checked. There is NO connectivity between any the five pins and the Connector housing. Must be using Tx and Rx as shield, Grnd ?


3/4 1335pF

1/5 1382pF

2/4 1298pF

2/5 1815pF

[boficle]

Thank you everybody, you have been a great help, thought I was having trouble with my counting, its all right now.