How Useful Are Antenna Tuners?
 

Hi, have IC-R75 with 30 ft random wire antenna. Would an antenna tuner such
as MFJ-956 significantly improve reception on 80-20meters.

Thanks

Martineau Gauda

No. The 956 is merely a tunable bandpass filter that allows a single
frequency through and rejects everything else. Being passsive, it has
insertion loss and will actually weaken signals.

It is very handy for receivers like the Lowe HF-150 which have no
front-end filtering, to prevent swamping the radio with strong local
MW, etc.

The R-75, with pre-amp 1 (not 2) on should hear everything on those
bands in your area.

On Fri, 24 Oct 2003 13:38:35 GMT, "Martineau Gauda"
wrote:

Hi, have IC-R75 with 30 ft random wire antenna. Would an antenna tuner such
as MFJ-956 significantly improve reception on 80-20meters.

Thanks

Martineau Gauda

Martineau Gauda wrote:

Hi, have IC-R75 with 30 ft random wire antenna. Would an antenna tuner such
as MFJ-956 significantly improve reception on 80-20meters.

Thanks

Martineau Gauda

I have an old Grove mini tun 3 that works fine with my ICR-70 and Drake R8. they
do help on the lower frequencies to match the antenna and receiver. above 14 MHZ
it is less useful here with my 155 foot longwire
--
73 and Best of DX
Shawn Axelrod

Visit the AMANDX DX site with info for the new or experienced listener:

http://www.angelfire.com/mb/amandx/index.html

REMEMBER ON A CLEAR DAY YOU CAN HEAR FOREVER

BTW, the 956 is a preselector, not an antenna ''tuner''.

On Fri, 24 Oct 2003 13:38:35 GMT, "Martineau Gauda"
wrote:

Hi, have IC-R75 with 30 ft random wire antenna. Would an antenna tuner such
as MFJ-956 significantly improve reception on 80-20meters.

Thanks

Martineau Gauda

On lower frequency bands, you can sometimes see an
improvement..............the reason for this is because you will be tuning
out the reactance in your antenna system, at the receiver end. If you have
capacitive reactance, you can insert inductive reactance of an equal
magnitude............if you have inductive reactance, inserting capacitive
reactance will cancel out that component, leaving just the resistive factor.
You can sometimes see a difference of 1 or 2 S-Units.
Because you are providing some selectivity with this tuned filter network,
receivers with a less than optimum front end can benefit, because of the
rejection of out of band signals that could otherwise cause some IMD
products.
With a good receiver, the benefits will not be so apparent.

Pete

David wrote in message
...
BTW, the 956 is a preselector, not an antenna ''tuner''.

On Fri, 24 Oct 2003 13:38:35 GMT, "Martineau Gauda"
wrote:

Hi, have IC-R75 with 30 ft random wire antenna. Would an antenna tuner
such
as MFJ-956 significantly improve reception on 80-20meters.

Thanks

Martineau Gauda