[Yaesu] 1000MP - Decreased Signal Strength on Low Bands

[Ken Claerbout]

I noticed during the CQWW CW contest this past November, that signals on 80
meters seemed unusually weak.  With all the solar activity going on that
weekend, I wrote it off to poor conditions.  Thinking about this a bit
further, I recall that over the past month or two, 80 meters has sounded
unusually quiet.  I decided to do a side by side comparison with my Kenwood
940 and promptly noticed that signals on 80, including power line noise,
were 20 dB weaker on my 1000MP.  No wonder I was having a hard time chasing
the weak DX stations!  Taking a closer look, I also see this happening on 40
& 160 although it was not apparent until now.
   I swapped the two rigs just to eliminate any potential problems with
cables, filters, or something specific to that operating position and the
problem followed the radio (1000MP).
    The radio is set for a tuned front end and when I switched it to flat,
using the broad front end amp, signals came back up on all three bands.
This would seem to indicate that there is a problem with the low band tuned
RF amp.  However, the diagram in the manual labels the range for this amp as
1.9 - 7 Mhz.  Is this front end section actually in use on 160 meters in the
1.8  - 1.9 Mhz range and also on 40 meters between 7 Mhz and 7.3 Mhz or is
the wide band amp used in these frequency ranges?  If it's the latter, then
that kind of kills my theory about the low band amp.  Is there anything else
setting wise etc. that I should be checking?
    In the event I have to get this repaired, I'd appreciate suggestions as
to where I should have this done.

73
Ken - K4ZW




--
FAQ on WWW:               http://www.contesting.com/FAQ/yaesu
Submissions:              yaesu@contesting.com
Administrative requests:  yaesu-REQUEST@contesting.com
Problems:                 owner-yaesu@contesting.com