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RFI from outside my radio ?

Jan 3rd, 11:47

N4AAB

Joined: Jan 16th 2013, 01:39
Total Topics: 0
Total Posts: 0
Looks, and sounds, like I am getting RFI from sources outside my apartment. I turned off all electrical items in my apartment except the fridge and my radio. So I know it isn't my flat panel television.

Sounds like standing next to a waterfall trying to hear a whisper.

I bought and added two RFI chokes to the power cord to the power supply, and two RFI chokes to the coax leading to my antenna.

I looped the power cord around them, they are squares, and they are touching.

If it reduced the RFI... I cannot hear the difference.

Any suggestions on how to fix this ?

Thanks !

Edit: I have an Alinco DX-SR8T, MFJ 936B loop tuner.
Jan 3rd, 19:45

W1VT

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0

http://www.arrl.org/radio-frequency-interference-rfi
You may find this page helpful.

Some noise on HF is to be expected--even in rural settings. Those in suburban and urban and urban areas typically have to put up with even more--when I lived in Philly the noise level was quite high on all bands--as it is in any major city.

Typically, for an those square ferrites to work at HF, you need to loop it around 15 or 20 times--with just a turn or two you don't get a significant amount of choking action.

Zack W1VT
ARRL Senior Lab Engineer
Jan 4th, 13:21

N4AAB

Joined: Jan 16th 2013, 01:39
Total Topics: 0
Total Posts: 0
Okay, I'll try that. I'm moving later this year to a semi-rural area. I don't remember much in that area in the way of street lights.
Jan 4th, 23:16

N4AAB

Joined: Jan 16th 2013, 01:39
Total Topics: 0
Total Posts: 0
The squares I have aren't big enough to do that with, but I did find that they can be connected together. I'll try that when I next get the chance.
Jan 17th, 11:20

N4AAB

Joined: Jan 16th 2013, 01:39
Total Topics: 0
Total Posts: 0
I tried making the 1:1 choke balun mentioned in 'Stealth Antennas' and it did reduce my RFI. I can hear some SSB chatter now on 20m.

The RFI is still there, but the AF volume control has an effect now.

Yes, the book that is available via the ARRL store.

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