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rack a pair of salvaged VU meters?

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August 29, 2004 9:47:48 AM

Archived from groups: rec.audio.pro (More info?)

Hi, I have an old Teac A-4300 r2r machine gathering dust. It weighs
too much to ship and no one wants it. (still works fine). I though I'd
salvage the meters and try and rack them with a handsome hardwood
faceplate for an extra reference, for something to do and so an older
technology might still live in some form. I have an old signal
generator, multimeter and scope. The Teac has RCA 1/4 jacks, it's not
a balanced setup. Can anyone make some suggestions as to how I can do
this at home in my spare time. Thank you, s.
Anonymous
August 29, 2004 12:48:41 PM

Archived from groups: rec.audio.pro (More info?)

In article <tuq2j0pte7599r5nvsmbgg5saqjodbehgb@4ax.com> nope@nope.com writes:

> Hi, I have an old Teac A-4300 r2r machine gathering dust. It weighs
> too much to ship and no one wants it. (still works fine). I though I'd
> salvage the meters and try and rack them with a handsome hardwood
> faceplate for an extra reference

> I have an old signal
> generator, multimeter and scope. The Teac has RCA 1/4 jacks, it's not
> a balanced setup. Can anyone make some suggestions as to how I can do
> this at home in my spare time.

Remove the meters. Put the tape deck back in storage. Use your
generator, multimeter, and scope to determine the sensitivity of the
meters, or more simply, put a pot (10K should do it) in series with
the meter and apply a signal at the level that you want 0 VU to
represent. If you're using a digital recorder or computer, this will
probably be in the ballpark of -20 dBFS. Then adjust the pot so that
the meter reads 0 VU. Then it's calibrated.

However, those meters don't have the ballistic characteristis of a
real VU meter and they'll bounce all over the place. You may have to
adjust the calibration experimentially in order to get a meaningful
indication on the meter. No matter what you do, it will probably
impress the visitors if you do a nice job of mounting the meters.



--
I'm really Mike Rivers (mrivers@d-and-d.com)
However, until the spam goes away or Hell freezes over,
lots of IP addresses are blocked from this system. If
you e-mail me and it bounces, use your secret decoder ring
and reach me here: double-m-eleven-double-zero at yahoo
Anonymous
August 29, 2004 1:21:12 PM

Archived from groups: rec.audio.pro (More info?)

spud <nope@nope.com> wrote:
>Hi, I have an old Teac A-4300 r2r machine gathering dust. It weighs
>too much to ship and no one wants it. (still works fine). I though I'd
>salvage the meters and try and rack them with a handsome hardwood
>faceplate for an extra reference, for something to do and so an older
>technology might still live in some form. I have an old signal
>generator, multimeter and scope. The Teac has RCA 1/4 jacks, it's not
>a balanced setup. Can anyone make some suggestions as to how I can do
>this at home in my spare time. Thank you, s.

The meters on those machines are not real VU meters. You can apply line
level signal to them with a shunt, and you may need to do some tinkering
to get the levels to be in the ballpark. But Teac really cheaped on the
metering... those things do not have VU ballistics or VU loading at all,
so it's going to be a matter of trial and error to get the ballistics and
the levels in the ballpark. With a normal VU meter, you just add a
3600 ohm series resistor and bridge it across a 600 ohm source and 600 ohm
load.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."
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Anonymous
August 30, 2004 12:23:35 AM

Archived from groups: rec.audio.pro (More info?)

mrivers@d-and-d.com (Mike Rivers) wrote in news:znr1093777132k@trad:

>
> However, those meters don't have the ballistic characteristis of a
> real VU meter and they'll bounce all over the place. You may have to
> adjust the calibration experimentially in order to get a meaningful
> indication on the meter. No matter what you do, it will probably
> impress the visitors if you do a nice job of mounting the meters.

And as an added bonus, you'll actually be able to see them in broad
daylight!. I've worked out where, in this day and age of LEDs which put
out thousands of millicandellas, where the old gloomy 3mCd ones go -
they put 'em in mixers, and they become invisible if you have to do a
job in the sun
(unless you carry a piece of black tatt and want to look like a 19th
century photographer) - which brings me to daft idea #1234 - really big
VU meters on really little mixers....
http://homepages.kcbbs.gen.nz/moby/wizvu.jpg
M
Anonymous
August 30, 2004 1:30:05 AM

Archived from groups: rec.audio.pro (More info?)

"spud" <nope@nope.com> wrote in message
news:tuq2j0pte7599r5nvsmbgg5saqjodbehgb@4ax.com...
>... I though I'd
> salvage the meters and try and rack them with a handsome hardwood
> faceplate for an extra reference,

They really aren't worth it, probably the weakest aspect of the machine. As
time gos by, SOMEONE is really going to need that machine. You might
approach a college music department or library.

--
Bob Olhsson Audio Mastery, Nashville TN
Mastering, Audio for Picture, Mix Evaluation and Quality Control
Over 40 years making people sound better than they ever imagined!
615.385.8051 http://www.hyperback.com
August 30, 2004 11:16:33 AM

Archived from groups: rec.audio.pro (More info?)

Thanks everyone.

On Sun, 29 Aug 2004 21:30:05 GMT, "Bob Olhsson" <olh@hyperback.com>
wrote:

>"spud" <nope@nope.com> wrote in message
>news:tuq2j0pte7599r5nvsmbgg5saqjodbehgb@4ax.com...
>>... I though I'd
>> salvage the meters and try and rack them with a handsome hardwood
>> faceplate for an extra reference,
>
>They really aren't worth it, probably the weakest aspect of the machine. As
>time gos by, SOMEONE is really going to need that machine. You might
>approach a college music department or library.
Anonymous
August 30, 2004 12:35:13 PM

Archived from groups: rec.audio.pro (More info?)

"spud" <nope@nope.com> wrote in message
news:tuq2j0pte7599r5nvsmbgg5saqjodbehgb@4ax.com

> Hi, I have an old Teac A-4300 r2r machine gathering dust. It weighs
> too much to ship and no one wants it. (still works fine). I though I'd
> salvage the meters and try and rack them with a handsome hardwood
> faceplate for an extra reference, for something to do and so an older
> technology might still live in some form. I have an old signal
> generator, multimeter and scope. The Teac has RCA 1/4 jacks, it's not
> a balanced setup. Can anyone make some suggestions as to how I can do
> this at home in my spare time. Thank you, s.

Whatever you do, be sure to ensure that the meters are effectively buffered
from the signal source. They have rectifiers inside them that are highly
nonlinear.
!