Good morning Hugh,
Tuesday, April 19, 2016
Thanks for the detailed reply, I have some good info to try there, I
need to improve my reception, for sure
Best regards,
Chris 2E0ILY mailto:[email protected]
> For LF reception there's no great secret. A decent communications
> receiver tuning down to 30kHz combined with a wire aerial broadly (or
> sharply) tuned to 136kHz, a correct loading coil should do the same job,
> this reduces broadcast signals to more acceptable levels.
> The receiver should have no attenuation below (say) 550khz, most of them
> have a bandpass filter on the front end, the older ones with a tuned
> front end were good but not stable enough. If you can get a circuit of
> the front end and re-draw it in a software program such as Tina it will
> display the frequency response and allow modifications to be set. I
> altered one inductor only. Beware of the remaining stations on Long
> Wave, it may require a notch filter, this is where software helps again.
> I think many transceivers for Amateur use have very poor, mediocre or
> just average receiver response at LF so I'm not sure if a preamplifier
> would help unless it's tuned.
> A notch filter on the receiver is essential and a good USB filter as
> well. It's worth buying extra filters according to the receiver as
> supplied. There is some choice but an internet search may help.
> Hugh, M0DSZ
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