was Re: [Johnson] More Valiant Progress now Meter Shunts

[C E]

John:
You may want to take a look at one of the back issues
of ER regarding the current situation (pardon the pun)
with the Valiant mA meter. Apparently, there had been
some issues with meter accuracy due to the errors
inserted by an incorrectly valued shunt. FWIW. Cal,
n6KYR/8

--- John Lawson <jpl15 at panix.com> wrote:

> 
> 
> On Sun, 27 Nov 2005, Kim Herron wrote:
> 
> > Hi again John,
> >        Ok, before you condemn the tubes, get out
> the REALLY accurate ohm 
> > meter and check your metering resistors.  I've
> never fouind any in either
> > a Valiant or Ranger that were right.  If those
> resistors are off, your 
> > current readings will be off and you'll condemn
> tubes that are just fine. 
> > You also load the rig
> > either too light or heavy depending on which way
> the resistors have moved and 
> > again, you get screwed up.  Oh, BTW, some of these
> resistors are NICHROME
> > wire, which make them look like a jumper on the
> terminal strip where they are 
> > mounted. PITA!
> 
>    This good advice, thanks!  The 6146s are all NOS
> - 'A's in the finals 
> and 'B's in the mod.  Throught this whole process I
> have been careful not 
> to let the tubes get red - one finger on the plate
> switch all the time. 
> So I think the tubes are OK - I'll give them another
> check on the Weston 
> 686 and see how they match.
> 
>    I don't know what the Valiant meter is,
> full-scale - anyone have the 
> meter terminal value in mA (I assume)....  I might
> have this info buried 
> in my Valiant Docs - or I could just put it in
> series with an mA meter and 
> resistor.
> 
>    I know where the shunt jumpers all are - and have
> a nice Shallcross 
> milliohm meter to check 'em with..
> 
>    Most of the 'problems' with the rig were cockpit
> error pure and simple - 
> not so much from a lack of Method, but were caused
> by the failure to 
> exercise Vigilance.
> 
> 
>    I'm ordering new capacitors for the RF section
> tommorrow.
> 
> 
> Cheers
> 
> John  KB6SCO
> 
> 
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