I have a 220V Micromega T-drive that I would like to convert to 110V. I've opened the chassis and next to the transformer there appears what looks like a jumper. I'd appreciate if anyone could offer any advice on how to convert this to 110V. Is it just a case of removing the 220V jumber and soldering in one at the 110V points?
Below is a photo of the jumpers. There are two 110V positions. Do I need to jumber both? Any US owners of a T-drive here that could check there units to see how they are jumpered?
Below is a photo of the jumpers. There are two 110V positions. Do I need to jumber both? Any US owners of a T-drive here that could check there units to see how they are jumpered?

It is quite certain that the *intent* of the circuit board is that you simply remove the 220V jumper & add the two 110V jumpers, making it 110-120VAC operation, it is VERY possible that the power transformer does not actually have split primaries that connect to those jumpers. Very common to have 220V-only trannies installed on jumper-select boards like that, especially after about 1985 or so. So, two choices to check: 1)Ohmmeter the resistance of the primary in 220VAC mode(from end of power cord w/power switch on or at the wire input terminals on board) and see if it drops in half when jumpers are changed. 2)Examine underside of board & see if actual trannie pins are soldered in to the traces attached to all jumper points, and if yes, change jumpers & try on 120VAC power.
Thanks Stephensank. I didn't consider that they may use a dedicated 220V transformer so will have a look under the board to see if the 100V points are connected as you suggest. I'll also do the resistance test just to double check.
I have the same issue on the T-Dac, however the transformer on that has a schematic printed on it which would suggest that it does have split primaries. What do you think?
http://www.diyaudio.com/forums/digi...elp-converting-micromega-t-dac-220v-110v.html
I have the same issue on the T-Dac, however the transformer on that has a schematic printed on it which would suggest that it does have split primaries. What do you think?
http://www.diyaudio.com/forums/digi...elp-converting-micromega-t-dac-220v-110v.html
Clearly, the dac absolutely will be 120VAC by 220V jumper removal & 2x 110V jumper installs. In my experience, printed schematics on transformers never lie. Does suggest that the transport will also have dual primaries.
Right, I checked the T-drive's transformer and it is soldered to the 110V tracks so it seems it's a simple case of adding the two 110V jumpers and cutting the current 220v jumper.
You can just see the tracks through the board connecting to the transformer.
Thanks for your help.
You can just see the tracks through the board connecting to the transformer.


Thanks for your help.
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