03-13-2018, 05:03 PM
>Any recommendations on a more permanent filter solution?
I'm glad you asked that... [Image: http://philcoradio.com/phorum/images/smi...on_lol.gif]
A couple of things come to mind. On some of the older FM sets the fm ant is connected the ac line thru a small value cap. At rf frequencies this cap looks like a short and couples all the noise that's on the line into the rf amp stage. So if your set has this configuration removing that cap would help.
More of an experimenter than a break out the slide rule and calculate kind of guy. If that being said I think something that looks like this may be helpful:
In terms of turns would start with about 5 and perhaps up to 20 choosing the number that give the best attenuation. You can also try connecting a wire from chassis ground to earth ground. This is made simple if you have hot water baseboard heat. You can just clip the ground ware on the one of the heater fins. Using the 3rd wire on the outlet isn't a good idea as you'll probably find more noise there. I'm sure there's someone smarter than I that has some better ideas.
GL
I'm glad you asked that... [Image: http://philcoradio.com/phorum/images/smi...on_lol.gif]
A couple of things come to mind. On some of the older FM sets the fm ant is connected the ac line thru a small value cap. At rf frequencies this cap looks like a short and couples all the noise that's on the line into the rf amp stage. So if your set has this configuration removing that cap would help.
More of an experimenter than a break out the slide rule and calculate kind of guy. If that being said I think something that looks like this may be helpful:
In terms of turns would start with about 5 and perhaps up to 20 choosing the number that give the best attenuation. You can also try connecting a wire from chassis ground to earth ground. This is made simple if you have hot water baseboard heat. You can just clip the ground ware on the one of the heater fins. Using the 3rd wire on the outlet isn't a good idea as you'll probably find more noise there. I'm sure there's someone smarter than I that has some better ideas.
GL
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
