[Hallicrafters] SX-42 S-meter blues

[Steve & Sharon Nordentoft]

Hi Rich,

Thanks for your insight!   
I too, thought about static build-up.  My experience with static and a meter was discovered on my Sencor, which is very sensitive to static.  The "breath" on the meter is a good idea, however, it didn't work for my case  Yes, my s-meter will park (zero) to the right side of the scale when powered off.  Unfortunately, I'm resolved to look further into it's bowels

73,
Steve
KA0BMQ


----- Original Message -----
From: Rich Oliver
Sent: Wednesday, August 31, 2005 10:01 AM
To: Steve & Sharon Nordentoft
Cc: Rich.Oliver at lowell.edu
Subject: Re: [Hallicrafters] SX-42 S-meter blues

Steve,

I don't know if this is the problem but it could be.  Most meters can be  
influenced by a buildup of static charge on the plastic or glass cover.  
  Back in the good old days when commercial broadcasting was heavily  
regulated and the operating engineer (usually the DJ with his Third  
Phone license) had to log meter readings at frequent intervals, it was  
well known that a reading slightly out of tolerance could usually be  
corrected by rubbing the meter face with a cloth until the static charge  
produced the 'right' reading.  A strong charge can 'nail' the meter in  
one spot with little regard to the actual parameter it is supposed to be  
reading.  One clue that electrostatic charge is affecting readings is  
when the meter doe not zero when power is off.  You did not say if that  
is happening.

If your goal is to get a true reading form the meter rather than the  
'right' reading, you need to kill the static charge.  The fastest and  
easiest way to do this is to breathe on the meter face and let the  
moisture in your breath drain the charge away.

Hope it is this simple!

Cheers, Rich, KC9GQ

Steve & Sharon Nordentoft wrote:
> Hi All,
>
> Sadly, after a full cosmetic and partial electrical restoration of my
> SX-42, it's s-meter now reads erroneously.  I replaced the zero-set
> pot and doubled checked the circuitry.  After proper calibration
> using the pot, the meter will not zero down and only will fall to
> about 7 on it's scale.  One stronger signals, the meter will only peg
> at just above 40 on it's scale and the needle tends to be a bit
> bouncy.  I'm somewhat baffled since the meter was operating properly
> even after my re-cap job.  The AVC operation does appear to me to
> operate properly.  The meter seems to work properly when using the FM
> function.  I replaced the zero-set pot with a new 500 ohm, 3 watt
> part.
>
> Any suggestions from the group as to what to look for would be
> appreciated!  Thanks!
>
> 73 Steve KA0BMQ
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