[ICOM] PW-1 Problems and a solution

[Jim M.]

Seems like a better design for the Icom family is for the power amp to have 
a control line back to the 746 (or 775 or whatever) that automatically 
disables the driver's tuner when connected.  They should start treating 
their drivers and linears as a SYSTEM, not just individual pieces.


----- Original Message ----- 
From: "Tony Visco" <ahv73 at verizon.net>
To: "'ICOM Reflector'" <icom at mailman.qth.net>
Sent: Saturday, March 25, 2006 9:47 AM
Subject: RE: [ICOM] PW-1 Problems and a solution


>
> Hello Fellow Hams,
>
> As usual, the learning process continues.  My PW-1 is on its way home from
> the Icom Headquarters after being repaired - Power Amp failure.
>
> First just a little background.  I have been a ham since 1970 building 
> many
> earlier pieces of equipment from scratch and later many Heathkit products.
> This is a hobby not my line of business.  I'm no dummy, but I was away 
> from
> ham radio for about 10 years and came back into the hobby last April 
> trying
> to get up to date on all the new technology that is now available.
>
> My station started slowly and gradually grew with the purchase of a used
> PW-1 in September/October to go with my Icom 746pro.
>
> Now I did suffer a problem with the PA's no longer being in sync. 
> Therefore
> no output.  Sent in to Icom and when I received the estimated cost I
> authorized the repair and asked to speak with the Service Department 
> Manager
> (Dan).  I really needed to know what would cause this situation since my 
> use
> of the PW-1 is very little.  With this failure, I was now considering
> selling the PW-1 for something less complex.
>
> But Dan was quite helpful and renewed my confidence in keeping the PW-1 
> for
> my compact shack.  Now I will admit I never gave it a thought but using 
> both
> antenna tuners seems to be the cause for my failure.  I normally work
> barefoot most times but when power is needed, I would merely turn on the
> PW-1 and keep going.  Most times tuning was no problem.  Now thinking back
> there were times when the 746pro and the PW-1 were fighting each other in
> trying to tune the antenna.  I might add that I have a Caroling Windom,
> Steppir Vertical, and a set of phased verticals on 80m.  Dan says that the
> internal fighting of the two tuners could blow diodes in the PW-1 and
> causing the eventual PA shutdown.
>
> His recommendation, use the PW-1 tuner only and not the exciter when the
> PW-1 is on.  Duh - go figure.  Makes sense to me, but I am a little
> disappointed that there absolutely no information in either manual to
> express this feature or caution for proper operation.  Some of you may
> consider this a common sense thing, but I bet there is a bunch of you out
> there that are doing the same thing.
>
> Anyway, that is my confession for today - I will always admit to my
> mistakes. Ham radio is still a fun hobby even if it costs a little for
> repairs.
>
> Tony W3EW
>
> ----
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>