I'm not much of a designer so basically MAR-6 with 100R from 5v supply
and 47nf caps for i/o coupling, the parallel tuned input just a ferrite
wound inductor (from a old TV board) and some caps to bring into
resonance on 136, it's not very high Q but it works to keep the
broadcast breakthrough out!
Nothing that complicated ... i like it to be simple!
I have replaced the wire on my Loop (now much lower resistance copper
wire, 2.5mm stranded) since last attempt and now is much sharper
response around 137 and much stronger signals than before too. The first
loop was about 20Ohms acros with the unknown 1mm wire i used ( shame
because i have miles of the stuff! ) now with the new wire is about 1Ohm.
Thanks to Alan about the tip on not connecting the sig gen directly to
the loop, it was quite a way out of tune! the simple coupling loop
worked much better..
Ready for some signals now....
Rob
Nick Mclean (SYD) wrote:
Hi Rob,
Do you intend to let others on the list have enough of a circuit
diagragm that they could replicate what you are building? I for one
would like to build a front end to "hot up: one of my rigs here.
73's
Nic McLean
VK2KXN / VK5ZAT
Tel: 02 99410619
Fax: 02 98139009
Mobile: 0417 822 728
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