Yamaha t-7 issues

Drum

Active Member
Just picked up a Yamaha t-7 that wasn't working. It looks like the battery leaked all over the circuit board and caused issues. It powers up partially.

My first two questions are
1 - Can I replace the nicad battery with a nimh or lithium ion? Not sure if the charging circuit will damage the other types.
2 - in cleaning up the battery leakage the solder pads from the board are gone. How do I get around this? Also having a hard time getting solder to stick on some of the nearby joints I am redoing.

I'll post some pics in a bit.
 
t-7 1.jpg

Here is a picture of the area under the battery, after some cleaning. I have since cleaned it further.

Tried to solder a few of the bad joints and the solder just balled up. I sanded the area and cleaned with alcohol. Would lead solder help? Also should i buy some extra flux to help the process - if so, what kind?

Thanks.
 
So I took some voltage measurements. I get 50 volts at -B, +B near the power caps with the power on. With the power off I get 12 volts. Doesn't seem normal. Still trying to decipher the schematics (can be hard to read in places and I am not an EE.

Below is the leakage area cleaned a little further. You can see the solder balling up and not really sticking. I have been cleaning and scraping, but still need to do more.

IMG_0634.jpg

Here is what the panel looks like with power on. Only one half lights up - nothing on the tuning indicator or the signal strength area.

IMG_0633.jpg
 
Measured the voltage (finally found the right spots)

+12 i get +2
-12 I get -2
+9 I get +2
9B I get +24.

Way off, so looks like problem in the power supply area as suspected.

One of the diodes (a zenner) that was near the problem area is a RD10EB2 and I can't find this on mouser or digikey. How do I cross reference to find an equivalent?
 
It's a shame no one chimed in on this. I have recently acquired this same tuner. The battery in mine did not do as much damage to the pcb as yours did. I plan to relocate the battery installing a holder remotely on the frame then wire it into the circuit. That way the battery is more accessible to change out if needed down the road. On mine the solenoid will bring the tuning wheel in but the motor does not appear to be functioning. Just started searching thru AK to see if there is any info out there on this.
 
One of the diodes (a zenner) that was near the problem area is a RD10EB2 and I can't find this on mouser or digikey. How do I cross reference to find an equivalent?
Old zombie thread. Must have missed this one way back when.
For future reference RD10EB2 is a 9.48 - 9.9 volt ,500mw zener diode
 
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