Hi Roger,
Am 24.11.2010 21:43, schrieb Roger Lapthorn:
Hi Stefan,
I am unclear about the connection back to the shack. Are you using
three wires (in the CAT5 cable) then to feed power, ground and signal
back to the shack from the FET?
No, i use 2 wires. One is GND and the other one is between drain of the
1st FET and its 390 Ohm resistor.
No isolation transformers etc?
In the first attempt, so now, i am using no isolation transformer. Since
i do not want to change the "official" grabber system but using the VLF
grabber PC for the tests, i am using the internal soundcard of the PC
(the official grabber uses a USB soundcard (5 Euro!)). This internal
soundcard's GND is the GND of the PC and circuit, so no difference with
an isolation transformer, just in this case!
Do you use this also on 136kHz and 500kHz with different filters?
Currently just on VLF but i plan to do some tests on 137 kHz as well.
Will inform you about the results.
73, Stefan
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