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Re: Unresponsive VU Meter Needle Mystery

Subject: Re: Unresponsive VU Meter Needle Mystery
From: "greg.winterflood" greg.winterflood
Date: Fri Apr 2, 2010 12:21 am ((PDT))
Thanks Dan. This is the same machine which you helped me with about 6 years=
 ago. At that time the "Record" LED would not light if I were outside on a =
cold winters morning. I was tentative about opening the machine, but you to=
ld me how to remove the front panel, which gave me the courage to do so. I =
discovered that the Anode of the culprit LED had been left long at the fact=
ory, so when the chassis contracted in the cold, the Anode made contact wit=
h ground. A simple snip off the long leg fixed the problem.

So, this time, as you say, I went back in like a Bull in a China Shop! But =
not before checking whether I could access a replacement VU meter. I couldn=
't find a mention of a Varta made VU meter, but India is turning out replic=
as and selling them in the UK.

http://www.andersestore.com/C360VUS-Circular-Vu-Meter-p/c360vus.htm

Anyway, I don't need a new unit as the needle didn't bend and, happily, it =
still resets to zero.

I recently bought an Olympus LS-10 for about a third of the price I paid fo=
r the PMD222. I was showing my teenage son the Marantz to demonstrate how f=
ar things had come from the bad old days before digital recorders. He recen=
tly had one of his hip-hop songs broadcast on Australian national radio (AB=
C Triple J). He thought the Olympus LS-10 had to be rubbish, because it was=
 so small and didn't come with a couple of seriously big microphones at the=
 front end. However, he didn't complain once he heard himself on playback!=


Thanks again, - Greg Winterflood.


--- In  Dan Dugan <> wrote:
>
> >  I swapped the Fluke to continuity mode, which carries a small current,=
 and applied the probes to the terminals of the VU meter. The needle jumped=
 around as if it were possessed. It will now peg to the right, on record, b=
ut only goes to -4dB on playback.
>
> OK, so it was mechanically out of the bearing or stuck somehow. Pinning i=
t probably bent the needle. You're being a bit of a bull in a china shop.
>
> The difference between record and playback probably depends on other fact=
ors, like the type of tape the machine was calibrated for and how the tape =
type switches are set.
>
> > I'm not sure, but it may have always behaved that way. The unresponsive=
 needle problem is rectified, but the mystery isn't. I wonder if anyone can=
 tell me why the needle moved a small amount when shaken, but required 'car=
dioversion' to do its job properly? Is it simply a matter of spindle lubric=
ation or something else? Cheers, Greg Winterflood.
>
> No lube, it's a jewel-type bearing. You'll want to adjust the mechanical =
zero of the meter--where it sits when the power is off. There may be an adj=
ustment near the spindle bearing for that, or not...
>
> Matching record and playback levels is calibration, and that requires tes=
t equipment and a service manual. Refer to qualified service people.
>
> But digital recorders can be had for what it would cost to rehabilitate i=
t, and they will make much better recordings.
>
> -Dan
>








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