Having thought long and hard on the subject I have just built and tested a
noise blanker with exceptional results.
The phase shifter with it's high Z input and output would not suit my low Z
noise aerial.... I also decided that the IMD of the map would be improved by
the use of a better amplifier.
For the phase shifter I used two Toko 3333 coils, the output of which drove
a MAR6 amp. Output level adjusted with a 1K carbon pot (in junk box).
I could not see the point of the added complexity of a quad filar
transformer, (coupled with the fact that I have suitable trifilars in
stock!) so used that.
First test to check sufficient gain in the system I fed the sig gen into
both inputs and monitored output on the scope.....perfect balanceobtained.
On the aerials and receiver a 9+10 signal could be nulled to S4.
Unfortunately we have had dry weather for weeks not and the power lines not
making a noise!.... I have to be patient!
Thanks to everyone for all the help and suggestions.
When I have learnt how to upload to my website (friend does it for me....
cannot understand computers!!) I will upload my circuit to there
73
Ian.... G3ROO/KG3ROO
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