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slug-tuned coils or substitutes?

I am trying to get some slug-tuned coils. I tried 4 different electronics stores and searched online. So far I can't find them. I found a few online, but not at the right uH value. I need them to make a notch filter to block out a radio station (or summat) that is interfering with channel 2 and 4 on my TV. The schematics and complete info are on this page:

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The last resort would be to buy an kit online for the notch filter, but it has lots of extra parts to make versions that I don't need. The coils I need are:

3.5 turn slug-tuned coil with aluminum core - 0.16 to 0.24 uH 5.5 turn slug-tuned coil with aluminum core - 0.06 to 0.09 uH

I can't even seem to find very many inductors of any kind that are under 1 uH in value. Anybody know where I can get these slug-tuned coils or what substitution I can make? I need to be able to vary the inductance so I can tune it to the right frequency to block out from my TV signal. Right now I don't know exactly what exact frequency it is, just that it's between 55 mhz and 72 mhz.

Reply to
wizzzer
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I forgot to mention I'm in Los Angeles county. So if you know a store I can get these at, that would be great. I've already tried All Electronics, Apex, and Radio Shack. I also went to where Panorama Electronics used to be, but they're out of business.

Reply to
wizzzer

Try Mouser or Digikey online.

--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida
Reply to
Michael A. Terrell

Have a look at:

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John

Reply to
jrwalliker

Toko makes that type of coil - S18 series, IIRC.

Leon

Reply to
Leon

Not being completely familiar with your situation (haven't read any replies either) - am just asking - might you consider (or have you) - a coax stub tuned filter? Put an appropriate "T" connector on the back of your set - place your actual TV antenna coax or whatever you're using on one side and a length of coax or equivalent of what you're using on the other side and cut it (the side NOT connected to your antenna) til it cuts out the interference. I had problems with a 2 way radio set up once and ended up doing that - took some cutting til I got to the right length, but BINGO - no more problem. I'm not sure if this would work in your situation - the system was more for 2 way radio issues - but easy enough to try without "hunting" for parts. Maybe it will work! I read about these in books, I've used one myself as I said. But oddly, I hardly ever hear of others using them.

There is a length you will have to start at - but I don't have the paperwork I had - in front of me to figure out the starting length. Maybe someone else here can toss in the frequency or formula. I've not used it in quite some time and it's TOO early in the AM for me to think. It seems to me (but don't quote me), it was a 1/4 wave of the frequency you're "correctly" receiving - not the "interference".

If the station is nearby - maybe the "engineer" can be of help. Usually - they are. If it is "cable" TV you have - maybe contact the Cable TV company - you "could" have leakage on your line.

Hope this might help - sure less aggrivating than trying to run down parts!

L.

Reply to
L.

With inductors this size, you can hand wind the inductors around a pencil or something of similar size and then spread or compress them after they have been soldered into some kind of board. The inductors in MOST commercial filters and tuners are made that way without coil forms.

David

Reply to
David

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