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Old January 11th 04, 04:34 AM
Circuit Breaker
 
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Mitar G. Kolac wrote:

I am interested in building a simple receiver to listen on 6m band. I
have tried to search the net but without success. Any suggestion? I have
some experience in building things from kits but do not have deeper
knowledge in electronics.


Since it's purely for receiving, I assume you don't have a license for it,
and are interested in the hobby in more depth than just hearing a bunch of
old men talk about the XYLs ;-)

Probably the cheapest way to /build/ one would be to scour the internet
for any kind of receiver schematic... I saw some not too long ago - I'll
make a note here to try browsing for it again (but it will have to be
about a week from now as tomorrow I'll spend most of my time doing work
for my dad and homework for college, then next week it's alllll school).
I MIGHT get a chance to do some stuff Tuesday, dunno...

Anyway, it's real simple, if you don't care too much about knowing exactly
what frequency you're listening to. You find a receiver schematic on the
net (I'll try to find one for you if you want), then instead of using the
coils described, you experiment with your own - larger diameter, longer
length, closer turns, further spread apart, center tapped, etc.

You'll need a variable capacitor. Probably best to go to the Dollar
General and pick up one of those cheapie $5 rotary tunable (the kind that
use a knob) handheld AM/FM receivers. Then, just steal the variable cap
out of it. It will have six leads on it, for 4 possible pairs (the two
middle leads are tied together (common). There will be a 20-40 pf pair,
and a 20-120 pf pair. The 20-120 will give better frequency spread, but
very coarse tuning and maybe a touch of selectivity loss. Still, with the
right coils, the 20-40 pf pair should do nicely.

In fact, now that I think about it, you might be able to make do with just
one of those by changing the coils (there are usually only 2 or 3 of them).

Wow, a $5 portable 6m receiver that can also pick up low VHF TV channels -
excellent!


FWIW, I've built an FM Broadcast band transmitter... only 18 parts, not
counting breadboard/wire/antenna/input/LED parts, and I get 1/8 mile range
on it. Anywhoo, I have been able to interfere with my TV (only a few feet
away) by using different coils and capacitor leads, so it should be fairly
easy to get what you want for cheap if you're patient and don't mind
fiddling with coils and such. Of course, it's not going to receive
beautifully, nor very selectively, but it should be able to pick up ppl in
your area.

Let me know if you want help finding a simple schematic - and I'm talking
just like 20 parts or so that you can pick up at the radio smack.

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