"Crazy George" wrote in message
...
I suspect someone replaced a failed movement in your original
meter with a standard movement.

Hmm, a light bulb flickers dimly in my brain. That would explain why it
looks stock but works backwards. The case of this meter is split to heck all
around and bound together with friction tape, but I figured that was not
that unusual for such old meters. When I opened the smallest electrolytic
can to restuff it, the danged thing split into about five pieces in my
fingers! But I could believe that somebody pried this case apart with a
screwdriver.

If you can engage a meter repair person, that movement can be made
right resting, and the leads reversed inside, and you will be back to
where you want to be.

Is this something a fumble-fingers like me could attempt? What's involved in
making a movement right resting? I have little to lose at this point . . . .

Check carefully and see if the leads to the meter are reversed on the
back. If they are, then
the second step above is not necessary, just return the wires to their
correct locations. But the mechanical internal
adjustment is still required.

Living dangerously, I reversed the leads on the back of the meter. Now it
behaves the same, but instead of zeroing at the middle (OK, the 7 marker)
and deflecting to dead left (the 1 marker), it zeros at dead left and
deflects off the scale farther left. So I assume further surgery is
indicated.

Thx again for any advice.

Regards,

Phil Nelson

Phil Nelson wrote:

Is this something a fumble-fingers like me could attempt? What's involved in
making a movement right resting? I have little to lose at this point . . . .

Assuming you're not serious about "fumble-fingers" - it is likely
"doable" - though it takes a LOT of patience and you will sacrifice some
accuracy (though IIRC the S-meter system in those radios were "relative"
anyway).

First you want to determine what type of meter movement it is -
hair-spring (likely), taut-band, or other (not likely). If it's a hair
spring (spring that spirals in - in a flat plain) and has both a front
and rear adjustment- then it's likely you can successfully "re-zero" it.
The front spring mount usually has a large loop adjuster that is often
engaged by an eccentric pin from the face that allows external zero
adjustments- the rear usually also has an adjustable spring mount - but
far more "dainty" as it's not intended for frequent adjustment - in fact
most are never touched after first calibration when made. It's this back
adjustment that you want to CAREFULLY turn until you zero the meter at
the right. Be very careful to not kink the spring, etc. - most meters
will have enough play to run them fully across using only the back
adjustment - though with some - you may have to use some of the front
adjustment as well. Since the meter will now be "unwinding" the springs
rather than winding it - the meter's linearity will be less than it
should be - but in this application - I doubt anyone would notice. Just
be sure and check for clearance around both springs as they flex as the
needle swings -- as again - the springs will be "un-winding" now rather
than "winding".

Once reversed - you'll have to experiment some to see how it reacts -
whether it appears that the indicated reading is what you would expect -
or if you need to "adjust" the circuitry a bit to better "calibrate" the
system.

HTHs -
--
randy guttery

A Tender Tale - a page dedicated to those Ships and Crews
so vital to the United States Silent Service:
http://tendertale.com

Phil Nelson wrote:
"Crazy George" wrote in message
...

I suspect someone replaced a failed movement in your original
meter with a standard movement.


Hmm, a light bulb flickers dimly in my brain. That would explain why it
looks stock but works backwards. The case of this meter is split to heck all
around and bound together with friction tape, but I figured that was not
that unusual for such old meters. When I opened the smallest electrolytic
can to restuff it, the danged thing split into about five pieces in my
fingers! But I could believe that somebody pried this case apart with a
screwdriver.

The meter enclosures in some variants of the SX-28 were famous for
cracking. Crap probably got inside the original movement after the case
cracked, and that's why it was replaced.

This problem is common enough that someone is actually producing a kit
to fix it. For more info:

http://bama.sbc.edu/Lloyd%20Godsey's%20Blooming%20Meter%20Fixer.htm





If you can engage a meter repair person, that movement can be made
right resting, and the leads reversed inside, and you will be back to
where you want to be.


Is this something a fumble-fingers like me could attempt? What's involved in
making a movement right resting? I have little to lose at this point . . . .

I'm not sure I would attempt it. I had a friend once that did this on a
replacement movement on a radio he was fixing (an SX-24, IIRC). The fix
involved reversing the little spring on the base of the needle AND
reversing the internal wires. Nerves of steel doesn't even begin to
describe the economy of movement required to do this. This guy was an
orthopedic surgeon, so it was something he did everyday. Mere mortals
such as ourselves shouldn't even try it. I would definitely take it to a
pro, or look for a replacement meter on eBay. They do pop up from time
to time there.




Check carefully and see if the leads to the meter are reversed on the
back. If they are, then
the second step above is not necessary, just return the wires to their
correct locations. But the mechanical internal
adjustment is still required.


Living dangerously, I reversed the leads on the back of the meter. Now it
behaves the same, but instead of zeroing at the middle (OK, the 7 marker)
and deflecting to dead left (the 1 marker), it zeros at dead left and
deflects off the scale farther left. So I assume further surgery is
indicated.

Thx again for any advice.

Regards,

Phil Nelson




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Nerves of steel doesn't even begin to describe the economy of movement
required to do this.

Well, that leaves me out!

I would definitely take it to a pro

Any recommendations?

Regards,

Phil Nelson

"Phil Nelson" wrote in message
ink.net...
Nerves of steel doesn't even begin to describe the economy of movement
required to do this.

Well, that leaves me out!

I would definitely take it to a pro

Any recommendations?

Regards,

Phil Nelson



Phil

If the replacement meter works properly,
and the modification was done neatly,
why not just leave it alone? If a good meter ever becomes
available, then change it out.

Not many folks would know, or care about the difference.

Pete

If the replacement meter works properly,
and the modification was done neatly,
why not just leave it alone? If a good meter ever becomes
available, then change it out.
Not many folks would know, or care about the difference.

I guess the honest answer is . . . that it bugs me. The replacement is
functional. On the other hand, it not only works backward but zeros near the
midpoint rather than all the way to one edge. So it can't be as responsive
on weak signals as if it had the full range of travel.

My plan for this SX-28 is that it'll be my "keeper." It's a one-owner rig
that worked well as found, unabused and unmodified except for this meter.
I'm taking pains with all the work to make sure that it's as squeaky clean
as I can manage. (Everything is easier the second time around!) I even went
so far as to restuff paper caps for a while, until I got impatient and
noticed how hard it would be to cram some of those big paper cases back into
the crannies whence they came, without disturbing lots of other components.

I suppose I could always change meters with my first SX-28 and then keep an
eye out for a replacement or just dispose of that set as-is. The thought of
having two of these beasts open for surgery on the same workbench is a
little daunting, tho' :-)

Regards,

Phil Nelson

"Phil Nelson" wrote in message
ink.net...
If the replacement meter works properly,
and the modification was done neatly,
why not just leave it alone? If a good meter ever becomes
available, then change it out.
Not many folks would know, or care about the difference.

I guess the honest answer is . . . that it bugs me. The replacement is
functional. On the other hand, it not only works backward but zeros near
the
midpoint rather than all the way to one edge. So it can't be as responsive
plan for this SX-28 is that it'll be my "keeper." It's a one-owner rig
that worked well as found, unabused and unmodified except for this meter.
I'm on weak signals as if it had the full range of travel.


Then it was a hack job and doesn't work right. It would bug me too.

Pete

On Wed, 08 Dec 2004 22:04:31 GMT, "Phil Nelson"
wrote:



I suppose I could always change meters with my first SX-28 and then keep an
eye out for a replacement or just dispose of that set as-is. The thought of
having two of these beasts open for surgery on the same workbench is a
little daunting, tho' :-)

Check this out:

http://cgi.ebay.com/ws/eBayISAPI.dll...sPageName=WDVW


Not an exact replacement, but pretty close. Only purists would see the
difference.

If you're not a stickler for historical accuracy, this one would
probably work too:


http://cgi.ebay.com/ws/eBayISAPI.dll...sPageName=WDVW

or this one:

http://cgi.ebay.com/ws/eBayISAPI.dll...sPageName=WDVW

or, perhaps you could buy one of these and take the cosmetics from
your old meter and mate them with the new one for a more authentic
look.

Just a thought.....

-Scott

Hey, and the price is right (at least so far :-). Earlier today, I received
mail from Doug M. indicating that an SX-23 meter should also work. So I have
a couple of alternatives to look for.

Thanks!

Phil

Hey, and the price is right (at least so far :-). Earlier today, I received
mail from Doug M. indicating that an SX-23 meter should also work. So I have
a couple of alternatives to look for.

Thanks!

Phil