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Jan Simons PA0SIM wrote:
Reading the schematics it is possible that the ANC-4 does not
fully cover the 360 degrees phase shift, just like the MFJ-1025.
But it is also possible that you experience more than one noise
source on 75 mtrs. A noise canceller (with two inputs/antennas)
can cancel only one noise source.
I have written about noise cancelling on my site, e.g.:
http://www.pa0sim.nl/Phaser%2080%20-%2010%20meters.htm
May be it can help.
73 es gl de Jan PA0SIM
Nice website, have you considered modifying the existing units (MFJ &
ANC)
to do what you have shown? Your idea would make either of these 2 units
much
better.
By the way, I took the sense antenna which is a short dipole and I made
one
leg vertical and the other horizontal. Now I have almost no noise on 75
meters. I haqve been playing around with this for awhile and it was either
all vertical or all horizontal. Now with this configuration the weak
signals can be heard.
Stan
AH6JR
Hi Stan,
I have considered it, but sometimes it is easier and better to start fresh.
First question is always: what phaser/noise canceller do you really want?
What do you expect from it?
Looking at the design of the MFJ-1025, it would take to much mods to
realize my needs.
When one of the antennas doesnīt hear the noise source, you donīt need
a phaser. But of course that antenna still has to hear your wanted signals.
Using a small loop antenna it is sometimes possible to null the noise
source.
I think playing with a short dipole, as you did, is the same as nulling with
small loops.
73 de Jan PA0SIM