PC-100 US Version

[Duane Hess]

I often type stuff in notepad over several days & paste into posts. Didn't notice Albertofenini and Maximilian's latest posts. I'll check my unit again. Maximilian's voltage measurements are very close to the schematic mentioned below.

Since Albertofenini has 110V & 220V versions, it'll be interesting to see what he finds. After all, we all know service manuals/schematics often often are not complete or different version levels.

Already typed the below, so now you must be punished! For your reading pleasure, but after the last 2 posts mine appears unnecesssary.

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I'm in the USA and most consumer electronics from the 70's did not have universal power supplies. i.e. if its rated 115VAC on the product label it will only take that rating. i.e. using a plug adapter to convert physical types would blow stuff up.

I have a PC-100C and looked inside. There was no evidence of additional tap points on the transformer; i.e. not convertable between 115/120 & 220V.
*** note the transformer always runs when the power cord is plugged into the wall. i.e. some circuitry is live with the power switch off. This allows the spare battery charging feature to operate. Wanted to point out the internal supply (mains) connections are not well covered should you forget its plugged in & open it.

I found schematics at:
ti58c.phweb.me/download/system/PC-100B_Printer_Cradle.pdf
airy.rskey.org/CALCDOCS//TI/ti59-pc100-schematic.pdf
airy.rskey.org/CALCDOCS//TI/ti59-service-manual.pdf

One of the schematics has the voltage ratings on the secondary (circuitry) side of the transformer. I'll dig it out again and measure the voltages on my unit. Which you would expect to match the schematic voltages on the secondary sides. A cursory examination of the two schematics (one was a user supplied UK 220V PC-100B) show my unit is identical/very close to the schematics.

Have errands to run & will take a while to dig in my spare room again. So maybe later tonight I'll have voltage values. Hopefully they match the one schematic. That imply there is no difference in power with 100B/C models.

I feel funny making a TI post. Having about 200 calcs, I have one whole TI setup (TI-59 and the PC-100).

It will be interesting to see what you all find.