Ed,
Yes it is. Manually operated dual pole ceramic knife switch, closed makes
the circuit and open just leaves the leads not connected to anything. I got
it at the Miami Tropical Hamboree about ten years ago.
It is exactly the correct distance between the two blades for the 450 ohm
plastic coated twin-lead that the Wireman sold at that time and has a white
ceramic base. One handle works both blades.
I once toyed with the idea of putting it on a different base and adding
another set of contacts to ground the lines when not in use, but it would
have been a difficult homebrew project. I decided to use the sparkplugs on
the outside of the wall with a 4" copper strap and solid #4 copper wire to a
20ft ground rod on the outside of the house for static discharge and DC
lightning ground.
I'm not sure if it keeps a constant 450 ohms across the device when closed,
but I work full legal limit with it no problem ever.
The only problem I ever had was on 75 meters, one phone in the house would
get interference, but I found that phone line was directly under the 80m
loop in the attic and was about 66 ft long. I shortened the phone line by 2
feet and eliminated the interference on that phone. I had a 75m antenna
going to that phone! <Har!>
I believe he sold all he had and that was it... discontinued. I wish I had
bought a dozen. Or two dozen. Over the years I could have helped a number
of other hams who asked about it. Well, hindsight 20/20.
Have you looked to Nebraska Surplus?
There's a big one on this page. Not the same as the one the Wireman had
tho.
http://www.surplussales.com/Switches/SWAssort-1.html
I googled "ceramic" "knife switch" and found this.
http://www.electronicsurplus.com/objects/catalog/product/image/img74716.jpg
http://www.electronicsurplus.com/commerce/catalog/product.jsp?product_id=74716
PEACE
Scott / W4PJ
As Tommy WD4K wrote, I'm the "other" Scott, not the "nice" one.
----- Original Message -----
From: "Ed Malmgren" <email address deleted to prevent spambots from culling
it and flooding Ed's inbox with spam>
Subject: Re: [TenTec] Remoting TT auto tuner
> Howdy Scott. is the knife switch you use a manual unit? I didn't find it
> in the Wireman. I am looking for the manual type. Thanks. Ed K7UC
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