In article ,
Lostgallifreyan wrote:

Hello. I've seen many 'boosters' for radio reception, none of which do what
I'm hoping for, so either my aim is foolish beyond imagining, or really
interesting. Please tell me which.

I hope to boost the incoming signal to override the ocal RF mush from nearby
flats, and to do this for a portable receiver so I want no cables attached to
it at all. I have considered two possible ideas:

1. Take a feed from my existing outdoor antenna and make a dipole indoors,
for passive re-radiation of whatever the outdoor one picks up.

This might help a bit, depending on how good a signal your outdoor
antenna gets, and on proximity between your indoor antenna and the
portable receiver.

2. Same thing, but using a small preamp I built once (uses a MAR6 I think,
about 22dB gain), but instead of feeding the RF input on a tuner as usual,
drive a small dipole to allow any small receiver with a whip or a wire to get
enough of the externally derived signal to beat the indoor mush.

(I think that feedback would be a problem, with any serious power, but
perhaps something as small as the MAR6-based booster I mentioned might work
ok, given that the outdoor antenna is several tens of feet distant.

This *might* work, but as you note it has some problems. Feedback
could very well be an issue (and could be quite unpredictable as it
could change from day to day or minute to minute depending on the
presence or absence of signal-reflecting objects near the retransmit
antenna).

Also, it may not be strictly legal. Your "booster" would be, in
effect, a miniature broadcast station, (re)transmitting the whole
spectrum (not necessarily just the radio stations that you care
about).

A single-channel (re)transmitter might be legal here in the U.S. under
Part 15 regulations... but boosting and transmitting everything that
got into the outdoor antenna could really be problematic. You could
end up making reception worse for your flat-neighbors, if the system
you were boosting/repeating interfered with direct reception of the
same signal.