On Wed,4/20/2016 6:29 AM, Jim Thomson wrote:
### By the time I buy 4 x torroids from one vendor PLUS shipping, then a pair
of
those special one off SO-239s he uses, no Z bumps, silver /teflon
/gold...PLUS shipping,
then double shielded teflon coax, with silver braids + silver center
conductor...PLUS shipping,
then a UV /water proof enclosure... PLUS shipping, then 4 of the one off nylon
tie downs, that
are machine screwed down...PLUS shipping....and assuming I have the SS hardware
on hand
plus the required gear to silver solder and terminate the ends, I decided I
will save next to nothing.
In fact, I would save nothing.
You would save a lot if you did what I recommended about 8 years ago --
get together a group purchase and buy in quantity. I've been part of at
least half a dozen, two of which I've organized. Appendix One of my
tutorial lists Fair-Rite part numbers of some useful parts and lists
several good industrial vendors who sell in quantity at great discounts.
Remember - we need these parts not only for feedline chokes, but also to
kill the many RFI sources that most of us have in our homes, and that
are in the homes of our neighbors.
## sometimes mucking about, dealing with in this case, at least FIVE
different vendors, and shipping
on all FIVE, assuming no screw ups, and hoping it all arrives intact, I spend
more time rounding this stuff
up vs building it. Shipping from USA to canada is not cheap.
I've also organized several group purchases of Amphenol 83-1SPs, and
assorted audio connectors of the type we use around the shack. I'd be
very surprised if there are no distributors of Fair-Rite and Amphenol in
Canada.
## I don’t see any plug and play cook book designs by anyone, that covers
the 2-30 mhz
spectrum, with a sky high 8-12k Z, that fits into a very compact 6 long x
4.375 wide x 2 tall box,
that weighs exactly 1.8 lbs.
Don't you recognize an advertising claim when you see one? I'm not
trying to sell you anything, I publish measured data on the chokes, AND
tell you exactly what's in them and how I measured them. Do you see ANY
of that in the magic boxes you're buying?
## he offered FREE shipping to Canada on a completed, plug and play unit. It
was here real fast.
I wish I had the megabuck worth of test gear to do my own experimentation on
CMC chokes.
Nobody has managed to overheat a CMC-230-5k....yet.
It's a brand new product, Jim! And you really believe a mfr is going to
tell you about his failures?
You will literally melt the traps in any
Mosely pro-96 yagi long b4 the cmc heats up. Ditto with the xfmr inside the
stepir yagi.
## To increase power handling capability of a CMC, there is a few ways to do
it, and that depends on
how much spectrum it has to cover. More cores + less turns is one technique.
WRONG!
Cascaded CMCs is another technique.... or a combo of both techniques. Sky
high Z + RS is another concept.
I published my take on this 6 years ago, and what I wrote about it was
not smoke and mirrors. I also have written about specific single core
chokes that failed at high power.
73, Jim K9YC
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