Metropoulos Forum

Hi. Looking for some assistance please. I am a rank amateur when it comes to this but am handy with a soldering iron and a multi meter and have successfully worked on Mesa amps to swap them over to 240 volt from 100 volt. Recently I have got into Marshall JCM800 amps and have a 1982 year Marshall 1987 model 50 watt amp that I imported from Japan. Its running 100 volt from a DRAKE 1202-324/2 Power Transformer and from my research I believe that these are a multi tap transformer and I should be able to change over the voltage from 100 volt to 240 volt. I would like to learn how to do this successfully and any assistance is greatly appreciated.

I have searched on the internet but cant seem to find the definitive how-to in order to change it over to 240 volt.
I know that I will need to change the power cord to a 240 volt cord and earth the cord to the chassis. I also know that when I double the voltage I need to halve the Mains Fuse amp. What I don't know is how to rewire and solder the correct wires from the switches and PT to change it over to 240 volt. Is it even possible with the DRAKE 1202-324/2 PT?

If it is possible how do I do it and is there anything else I need to change apart from the cord and the mains fuse?

Happy to provide further pics and information.

At the moment I cant load any pics, will I have to reply to my own post to do this?

Regards
Dane Z

Not saying this is 100% right but, this seems to be a similar issue.

Just be careful, I don't want you to blow up your amp.

The transformer is 1202-324/3 instead of 1202-324/2. Don't know if color codes changed?

Check it out anyway, it might help.

viewtopic.php?t=38194

There is also the post for 1202-324. No number after the /

https://forum.metropoulos.net/viewtopic ... 22&t=32287

Hi Paul

Thanks for the advice and links.

I ended up taking it to my amp tech, just to be on the safe side and this is what ended up happening. It was fairly straightforwarded but only for this particular amp. Other Marshall amps may be different.

I was discussing this on another marshall forum and here is the link where the issue was resolved.

https://www.marshallforum.com/threads/m ... pt.123867/

Thanks again. It is always reassuring to know there are people willing to give their time and experience to these forums.

Dane Z