[1000mp] Mark V high SWR with amp

[J. C. Mc Laughlin]

Dear Michael:
    As I recall, the Alpha 99's input is a 50 ohm resistor.  If you see
anything other than a small SWR it suggests either the resistor, its
connections, or the connectors/cable between FT1K and Alpha 99 are
defective.  Since straight through seems to be normal (amplifier off), that
suggest that the 50 ohm resistor or its circuitry is now defective.

    The overload circuitry in the Alpha 99 is so fast that it seems unlikely
to be able to burn out the resistor.  I use the same connection/combination
and the one time that I inadvertently drove the input with too much power,
the amp cut off right now.

    Nye Viking Tuner, even if the "big" one, has been known to arc under
power.  Even so, if the tuner is on the output of the amplifier, one should
still see the 50 ohm resistor on the input of the amplifier.

    Good luck and tell us all what you find.   73   Mac   N8TT
J.  Mc Laughlin;   Michigan  U.S.A.
Home:  JCM at Power-Net.Net
----- Original Message -----
From: "Michael W Elliott" <kq0b at sbcglobal.net>
To: "All about Yaesu 1000mp" <1000mp at mailman.qth.net>
Sent: Sunday, February 06, 2005 11:41 AM
Subject: Re: [1000mp] Mark V high SWR with amp


> Well let me replay the descriptiomn.
>
> The amps are Alpha 99 and Alpha 89.
>
> These are modern amps.
>
> Next:
>
> The swr on the out meters of a Bird and Nye Viking Tuner show output swr
fine.
>
> Swr on amplifier says ok
>
> SWR when running barefoot no problem on the rig.
> Once I switch on the amp the problem occurs.  Seems like there is a
mismatch back to the input side althought the output side says everything is
ok.
>
> I will call Yaesu on Monday and describe the situation.
>
> Only other thing  I can think of is NKE Viking tuner being in line.  Gonna
take it out of line and run and see what happens.  Would sound strange if
the tuner but could be possible.
>
> Mike
>