bounty hunter 10" search coil

[serhatsehri]

Hello
how to make 10" search coil for bounty hunter land star model.
can you send me how wire and how turn and how mH .
thanks

[Unregistered]

Coil Measurements

The coils on my Land Star's 8" measure as follows: TX = 3.23mH (yes, mH) and RX = 3.36 mH. Inductance was measured in parallel mode. They show a Q of 1.7 for TX and 2.9 for RX. Resistance is 8.6 Ohms TX and 606 Ohms RX. During operation, TX has a 5Vdc bias on one end and a 20Vp-p sine on the other which is at 6.5 kHz. Rx shows "no" signal until metal object is introduced and then a small sine wave will show up. With no coil connected, there is a ramp present at the TX coil connection that switches off every 164 ms (~6.8 Hz). I hope this helps! I'm in the process of designing a coil that may be drawn behind a horse. Hopefully, it will be far enough from the metal shoes!
Jeremy

[Unregistered]

errata

Sorry, that should read 6.6 Ohms for Rx, not 606.
Jeremy

[Jeremy]

'scope of Land Star TX


Land Star TX output, 1k Ohm load (no coil)

[Jeremy]

TX output with 1k Ohm resistor, no coil. I was pinched for time in the lab but this is what I could do really fast. DC coupled probe, ground is center graticule. Opposite polarity pulses 27 ms apart.

OK, I'll try pasting this jpeg one more time and then I'll shrug it off..
See attached?
Jeremy