Someone asked a while back for information on sources of RFI Suppression
Ferrites. Here are some places I am aware of:
Very large selection of ferrites -- have very helpful Hams on staff. They
will send you a catalog and RFI tip sheet upon request. I have ordered from
Palomar and am satisfied with them.
Ocean State Electronics
Fair selection of ferrites and better prices. I have ordered from Ocean
State and am satisfied with them.
Kits and Parts Dot Com
Fairly small selection of ferrites, but some great prices on FT114s (5 for
$5) and FT240s ($5 each)! They only accept mail orders or Pay Pal. I just
placed an order for a few FT240s, but haven't received it yet.
Very good article on the use of ferrites for RFI suppression:
I've been told that material 43 ferrites are good for general HF RFI
issues. However, I've also been told that material 77 is best below 5 MHz
and material 43 is best 7 MHz and up (within the HF spectrum).
73, Michael N9BDF
PS The "Amateur Radio Emergency Communications Consistency Act" (HR 1417)
and the "Amateur Radio Spectrum Protection Act" (HR 713 & S. 537) have been
reintroduced in Congress. Please contact your Congressmen to ask for their
support of these bills! See the following ARRL link for details:
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