[amsat-bb] Re: Trackbox interfernces

Enzio,

When I built my T_B years ago, I added some small ferrite chokes inside the aluminum box for the CAT, power, and rotator control lines. Since there should be no RF, the values are not critical. Mine came from my junk box. I did not need them, but some small bypass capacitors at the inputs might help. Using an aluminum box with good shielding resulted in no RF noise.

You might try a good external RF clamp on choke on the external lines. This should at least allow you find where the problem is. Don't forget to check the LCD display if it is not one or more of the lines. Some of them can also radiate. Finally, a conventional noise blanker is often effective with impulsive noise.

Good luck,

Alan WA4SCA