[R-390] Meters

Thu, 08 May 2003 23:50:31 -0400

Scott and other Gents,

The amplified meter gambit has been discussed in "Solid State New" a few years
back, complete with a picture of the mounting system on per board.   But yes, it
has been done before...and opens the door to comparatively easy metering up of
those 'pure' rigs with the big holes in them...

Keep an eye on the boxes under the tables gents...the meters are out there...and
are very usable...as are occasionally the back lighted meters...about half of
those found are center scale meters so not as usable...

For the purists out here...My five of my R-390X's are up an running now, some
are with all original metering, some with mixed meters, and one with mixed
meters that is documented  "original retro fit by the Navy under at sea
conditions....that don't match...one white face (Db) and one black..."

So whatever pure is...enjoy...but don't get your shorts in a knot over it . . .
In fact, no one has ever seen my R-390X stable and been able to tell whether my
paint jobs are new out of the box or re done, or some with battle scares ....
and like wise for the metering, or the now customized dial skirts...on my
favorite ST. J Blue...with it's freshly machined shaft clamps...that are 'not
original'...

Have fun gents...es 73,

Gene

"Scott, Barry (Clyde B)" wrote:

> Not original, but better than two big holes in the front panel  :)
>
> Anyone been there / done that?  I seem to recall someone doing this.  If so,
> can you repost?
>
> Thanks,
>
> Barry(III) - N4BUQ
>
> -----Original Message-----
> From: pete wokoun, sr. [mailto:[email protected]]
> Sent: Thursday, May 08, 2003 10:49 AM
> To: [email protected]
> Subject: RE: [R-390] Meters
>
> Ahhhhh, therein lies the problem!  This meter only requires 17 millivolts
> across it to achieve full scale deflection.  This makes it a very sensitive
> meter.  Typical meters of this size are higher resistance and require 60-100
>
> millivolts or more for full scale deflection.  You can get the right
> resistance or current but getting them both together is what makes these
> meters 'special'.
> One trick used is to get the right resistance with a shunt and use a small
> DC amplifier on a piece of perf board to drive the meter to get the right
> current.  But then, this isn't 'original', is it?
>
> pete KH6GRT
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