[Boatanchors] Weirdo!

[mikea]

On Mon, Jun 18, 2007 at 09:59:10AM -0700, Ken wrote:
> Fellows,
>
> Here is one for the books! I don't begin to try to explain it. You
> figgure it out!
>
> My Midland Model 23-126 Standing Wave Bridge quit reading reflected
> power! In "Forward" it adjusts ok but when I switch to "Reflected"
> the needle goes to about midscale and remains there regardless.
>
> I discovered by experimenting, that in Forward if I dipped the two
> tuning condensers on the Johnson Antenna Tuner, not the KW model,
> the signal reported was good, best I had been getting. By bringing
> the needle up with the adjust potentiometer and then dipping,
> stations report my signal up and good. The transmitter is a Central
> Electronics 100V. Reminds me of "dipping the final plate on an
> amplifier".
>
> Something in the SWR Bridge circuit has changed that results in this
> weird effect I presume. It is not acting like a field strength meter
> which you would tune for maximum reading!
>
> Puzzled! Take care,
>
> Ken N5CM

Check the diodes in the bridge; I suspect you'll find that one of them
is a monode or a nonode.

Or I may just be showing the effects of a sleepless night. GL anyway.

-- 
Mike Andrews, W5EGO
mikea at mikea.ath.cx
Tired old sysadmin