220V to 240V for 1541 / 1570
Project: Modify drive for 240V operation.
Target : 1541 (not 1541-II), 1570
Time : 20 min.
Cost : 0. Zero. Null. Nada. Zilch. Nothing.
Use : - Reduce/avoid read errors
- Enhance drive's lifetime
Connect the input line to the remaining input of the transformer.
The transformer of very many 220V-1541s and 220V-1570s is prepared
for 240V operation. You just have to resolder the drives voltage
input line to the 240V line of the transformer.
This can greatly reduce the heat generated, which is very often
the cause of read errors. Above that, it enhances your drive's
lifetime, since the European mains voltage has changed to 230V in
- Pull off all cables and open case.
- Remove the printed circuit board.
- Now you will see the transformer, the fuse holder and the
power jack. There are four wires leading from the transformer
to a plug which connects to the PCB. The remaining three
wires belong to the input of the transformer; one of them
should be soldered to the power jack, one to the fuse holder
and one unconnected.
If you have an ohmmeter, proceed as follows: Move the power
switch to the ON position (the drive should stay unplugged)
and measure the resistance between the two outer pins of the
power jack and write it down. Then measure the resistance be-
tween the unconnected wire and each of the other two wires
(one going to fuse holder, the other to power jack). When the
measured resistance is slightly above the value you wrote
down, you have found the wire which has to be unsoldered and
where you have to solder the yet unconnected wire. If the re-
sistance is way below the value you wrote down, you found the
wire which you should not touch :-)
If you have no access to an ohmmeter, unsolder the red wire
connected to the fuse holder and solder the black wire to
it instead. It is very likely that this is correct (at least
this applies to all my floppy drives), if it is not, replace
the fuse you have blown, resolder the old wire to the fuse
holder and replace the wire you did not touch yet with the
- Re-install the circuit board; close the case, but do not
tighten the screws yet.
- Plug in power cord. CAUTION! Do not open the case until
you pulled off the power cord again!
- Switch the drive on and see if it works. If it does, turn
it off and tighten the screws.
- You did not attach the wires to the right connection.
Updated: October 9th, 1997
Created: February 4th, 1997
Status : Verified on October 9th, 1997
Site copyright © 1997 by Marc-Jano Knopp
This document is part of MJK's Commodore 64 & LCD Page
Brought back to life by Peter Schepers, Dec 10, 2005 because I really liked this site!