While preparing to make a group purchase for several local clubs, I've
learned that Fair-Rite now makes a 1.4-in i.d. #31 clamp-on. It's 2.5-in
long, and is the equivalent of five of the 1.4-in i.d., 2.4-in o.d. #31
toroids. A big part of the great news is cost -- we're buying 390 pieces
at a cost of $9.30 each. We were quoted $10.34 for 60 pieces (two boxes
of 30). The last time we bought toroids we paid about $4 each with
shipping for 1,100 pieces. That means that we're buying the big
clamp-on for less than half the cost of the equivalent five toroids!
And it means that we have a clamp-on large enough to hold 7 turns of
RG8/RG213-size coax without removing the connector.
The new part number is 2631181381. Although it's listed as a
suppression part, it carries the part number of an inductive component,
so there are no impedance curves on the online data sheet. I asked, and
they promptly sent me a pdf of Z for 1, 2, and 3 turns. 3 turns shows
the resonant peak of 2.8 KOhms at about 24 MHz.
I got quotes from Mouser (very high), Kreiger (better), and Arrow. Arrow
didn't know about the part and couldn't find it in their catalogs.
Dexter gave us the best price and got our order.
73, Jim K9YC.
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