Ye Olde Korg Chromatic Tuner WT-10A

[oc disorder]

korg chromatic tuner WT-10A service manual
I know this is just about the first thing Korg ever made.
Keio Electronic Lab,Corp Tokyo Japan
This one is in perfect nick even the vinyl pouch - unfortunately it got dropped
recently by an over enthusiastic user and would like to get it going again for the owner.
The oscillator/tone functions ok but no meter reading.
Cannot see a crystal although there is a black sealed component which I suspect is some kind of resonance device...
I guess as the tone function works the osc circuit is working.
Suspecting the meter itself so even the specs of the meter may help.
Thanks

[vintagekiki]

Korg WT10 Guitar Tuner

[Enzo]

Before spending time on it, do check the meter. Meters are meters, so it should be easy to see if it deflects or not with a small current applied. The meter movement by far is the most fragile part of it.

160uA movement? There is one I don;t see in catalogs.

[FenderJ]

Korg WT10 Guitar Tuner

Awesome!

Hey, what are the chances you've got the original users manual someplace? I just inherited one of these bad boys and I'd like to learn its quirks before I play with it.

[Enzo]

Don't have, what do you need to know? Tuners are all kinda the same. SOme make tones to tune against, some don;t. There'd be a SOUND selection somewhere on it. WHatever note you want to tune, you select with the knob or on newer units by stepping. Many have an internal microphone, so you can just sit it there. If you plug a guitar into the input jack, it turns off the mic part. SOme have an output jack so you can just leave the tuner in between the guitar and amp. SOme will have a note adjustment so you can set the reference pitch. SImpler units will just have A = 440Hz, but fancier ones will allow you to set the A to a range. SOme guys tune down to A=400 or something to accomodate the singer or to allow the guitars to tune down some for string action.

[vintagekiki]

Korg WT10 Guitar Tuner

http://elektrotanya.com/Korg_WT10.GIF/download.html

[oc disorder]

A postscript four years later.. You were spot on Enzo. It was the meter.
It had been dropped and one of the fine springs that keep the needle centered and provide the supply to the armature
had come adrift at the actual solder point.
Well at that point I should have quit but considering I had nothing to loose except perhaps another attempt I dived in !
Was like trying to do smd work with a plumbers iron !
With toothpicks and sticky globs I managed to hold it enough to re solder it and after a bit of a tweak to put it on zero
I called it finished ! Don't know if its still going but as I haven't heard I assume so.
Moral to the story.. don't drop devices with moving coil meters!! aka next time tell him to buy a new one !