Vintage Synth Repair

I just picked up a 200A tonight... very nice once I cleaned her up a bit. Once I have it turned on for a while, the output gets very scratchy, so I figure I have some tinkering to do. First things to check?

Deke The Geek

Does it get scratchy when sitting idle, or when you turn the volume control,
and is the "noise" level controlled by the volume control, and does the
vibrato have any effect on the noise? Is the noise present at the headphone
jack? When you play the keys, are there certain notes that increase the
"noise" and do all the keys work, and sound relatively in tune? 

Keith Niver
Master Certified Wurlitzer Tech

-----Original Message-----
From: Deke The Geek [mailto:deke@...] 
Sent: Thursday, January 09, 2003 2:37 AM
To: vintagesynthrepair@yahoogroups.com
Subject: [vintagesynthrepair] new to the group - 200A


I just picked up a 200A tonight... very nice once I cleaned her up a bit.
Once I have it turned on for a while, the output gets very scratchy, so I
figure I have some tinkering to do. First things to check?

Deke The Geek


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>Does it get scratchy when sitting idle, or when you turn the volume control,

The scratchiness isn't a result of a dirty volume pot (I don't think so anyway), but yes... it does it at idle.

>and is the "noise" level controlled by the volume control,

Yup!

>and does the vibrato have any effect on the noise?

I don't think so.

>Is the noise present at the headphone jack?

Yes. It's present on internal speakers and externally through an amp.

>When you play the keys, are there certain notes that increase the
>"noise" and do all the keys work, and sound relatively in tune?

I think there is one key that needs I little more clearance... the second F key from the bottom. It's not bad, though. Other than that, all the keys work well, and sound in tune. This is a very cool piano. I took it apart last night and checked out the insides... the keying mechanism is amazing. When I put it back together I had no vibrato... took it apart again and realized I had a loose ground connection on the left end of the metal cover over the tines (is tines right?). I secured the ground and it works properly again. BTW, I only have two of the legs... does anyone have spares to sell?

Deke The Geek

I just got your return message tonight, but I am leaving early tomorrow
morning for a weekend conference. I'll look up my notes and schematic when I
get back. Try removing that one reed and see if it has any affect. It could
be a noisy input transistor or resistor before the volume control. I'll do
more checking later.

Keith  Niver

-----Original Message-----
From: Deke The Geek [mailto:deke@...] 
Sent: Thursday, January 09, 2003 4:17 PM
To: vintagesynthrepair@yahoogroups.com
Subject: RE: [vintagesynthrepair] new to the group - 200A


>Does it get scratchy when sitting idle, or when you turn the volume 
>control,

The scratchiness isn't a result of a dirty volume pot (I don't think so
anyway), but yes... it does it at idle.

>and is the "noise" level controlled by the volume control,

Yup!

>and does the vibrato have any effect on the noise?

I don't think so.

>Is the noise present at the headphone jack?

Yes. It's present on internal speakers and externally through an amp.

>When you play the keys, are there certain notes that increase the 
>"noise" and do all the keys work, and sound relatively in tune?

I think there is one key that needs I little more clearance... the second F
key from the bottom. It's not bad, though. Other than that, all the keys
work well, and sound in tune. This is a very cool piano. I took it apart
last night and checked out the insides... the keying mechanism is amazing.
When I put it back together I had no vibrato... took it apart again and
realized I had a loose ground connection on the left end of the metal cover
over the tines (is tines right?). I secured the ground and it works properly
again. BTW, I only have two of the legs... does anyone have spares to sell?

Deke The Geek




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vintagesynthrepair-unsubscribe@egroups.com

 

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<<I just got your return message tonight, but I am leaving early tomorrow
morning for a weekend conference. I'll look up my notes and schematic when I
get back. Try removing that one reed and see if it has any affect. It could
be a noisy input transistor or resistor before the volume control. I'll do
more checking later.>>

Actually it's working fine now. I opened the case to clean everything up once more, and to check all the connections, especially the ground wires. Of course, all of these were still tight from when I tightened them last night... LOL! But just as I was about to put the cover back on I bumped the little PCB board with the amp and such on it... it moved! I tightened the offending screw, plugged her in and she works like a champ.

While I was so excited about this development, I was reading the archives today and noticed it was recommended to use the AUX output for a line out to an amp. I had tried plugging mine in there before, but had no output. I figured that the pot next to the AUX outlet was for trimming the output, so I tried turning it to no avail. I got out the trusty socket set, pulled it loose and noticed the sheathing was pulled back a little, allowing the wires to ground out I assume. I pushed the sheathing back down and taped it up to prevent it moving again... now I have volume!

Now I was stoked! I hadn't taken the time to clean up the pedal yet, so I dove in. I assumed this was a plastic replica of the pedal... which is worth it's weight in gold if you don't have a pedal. So I was just happy to have a pedal at all. I pulled it apart to blow the cobwebs out and found that it was actually the original wooden pedal... the plastic coating or whatever threw me off. So of course I was happy to see the original pedal.

Then I came in to check my email and found a note from the guy I bought the piano from. When I picked up the piano last night, he had only brought two of the original legs, and said he didn't think he had any more but that he would look. I bet you guessed already what his note was about... he found the other two legs! So now my piano will be complete, with the minor exception of a seemingly aftermarket speaker that replaced an original.

All of this for $150!

Maybe I should go buy a lotto ticket or two?

Cheers, and thanks for all your advice.

Deke The Geek
-happy camper... er, player-