Steinberger GL User manual

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Replacing the potentiometers on a Steinberger GL: passive HazLabs board
original
board
new pot
After facing a number of HazLabs boards with a crackling or other-
wise defective volume pot, I started a desperate search for pots that
might be used as a replacement. Without sucess, no pot available in
stock anywhere had the required values and dimensions. So I had
them made on custom order from STATE Electronics, the providers
of the original pots. It was not possible to get the exact length of
the bushing (no longer manufactured as an option), so the most
important question is: WILL THEY FIT?
I had already successfully tested them on the active HazLabs EQ
board, so the next project was mounting them on a passive board
of a 1986 Steinberger GL-4T. The length of the bushing is a critical
factor there. This is how to replace the pots on such a board:
1. Open the housing of the GL, take o the knobs, and remove
the nuts and washers holding the two pots. The board comes
loose now.
2. Unplug the two connectors. Do NOT just pull on them, they
have a locking mechanism you have to press down before
removing them.
3. Remove the nuts (usually two per pot) which hold the pots
on the board (see right hand pic on top).
4. Now to the dicult part: you need to unsolder the three pins
of each pot.
CAUTION:
If the soldering pads get too hot, they will separate
from the board. Be careful not to apply to much heat or
mechanical force with the tip of the soldering iron a!
I’ve used a mechanical desoldering pump to remove the
solder from the pads. If you don’t have such a pump, use
solder wick to get the pads (or better: the holes) solder free.
You can also cut the pins of a defective pot before using the
soldering iron, in order to remove the pins individually from
the board. This is less dicult than desoldering the whole
pot with all three pins at once.
5. Mount the new pots. Stick the pins through the holes on the
PCB and fasten the pots with one toothed washer and one
nut.
6. Solder and cut the pins. Again, take care not to overheat the
pads.
7. When done, mount the board on the faceplate of the guitar.
The remaining length of the bushings should be about 8 mm,
which is sucient for the GL faceplate.
connectors
soldering pads

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8. Fasten the board using the corresponding washers and nuts.
9. Plug in the two connectors.
10. Mount the knobs and re-attach the faceplate.
11. This list has only 10 steps. Done :-)
Bernd Meissner • [email protected]
http://www.headless-europe.eu/Bernds_Guitar_Pages/Parts_2.html