[R-390] OT: Looking for TS-352 or AN/URM-105 or 1000ohm/v tester

[Roy Morgan]

At 09:35 PM 3/19/2005 -0500, Flowertime01 at wmconnect.com wrote:
>Gary KB1FBI.
>
>I think the TS-352 is a battery powered meter. If was surplused out
>as it used some non standard shaped batteries. If you find a meter,
>you likely cannot find batteries.

If *I* remember correctly the TS-323 is a very heavy, indestructible VOM 
with cover and handle.. fine for boatanchor work but you have to move the 
probe lead to change ranges on it.  Not all that convenient.  Neat meter 
however.

The batteries were two (?) three-cell batteries with screw terminals on 
top.. you can simply solder together three AA batteries and put them into 
the battery compartment.  The batteries are only used on the OHMS 
scale.  There may also have been a D cell for the lowest range.

If anyone has one of these and needs a manual, I think I have a copy 
here.  I also have a manual for the TS-505 VTVM mentioned in the R-390 
repair and alignment procedures.

The TS-223 is another animal, a much more modern, plastic cased unit that 
used mercury batteries.  You can solder two sets of three AAA cells and put 
them inside the meter case just fine.  The C cell it also uses is common 
and goes in the normal place for it.. The batteries are used on the ohms 
range, the mercury cells ran a single FET for the ohms detector 
circuit.  The FET is NOT used on voltage measurements, so hamfest hawkers 
who tout them as FET-input meters are stretching the facts.


   I thought a TV 7 was a tube tester. What are you doing that is so
>exact that you are worried about the voltage reading you are getting
>from you today's meters with there higher resistance per volt?

Adjusting the signal voltage in the TV-7 is the most critical setting, I 
think.

>  Did I say R390?

Yes, you did. AND, a proper checkout for any TV-7 is to test all the tubes 
in all of your R-390's.

So there.. :-)

Roy

Roy Morgan
K1LKY since 1959
7130 Panorama Drive, Derwood MD 20855
301-330-8828 home .... 301-975-3254 work
roy.morgan at nist.gov