I'm not sure what the exact mech. is, until I find mine + look inside. But I recall it was a fairly narrow (approx. 2" wide) one - similar size to Anritsu MD6420 Data Transmission Analyzers built-in printer, compared with wider (approx 4"?) type built into some old large Gould DSO's. However, the Microdoctor case is quite low-height, so probably has much-smaller mech. as till-roll is external - as no room to hold it in unit.
But, from quick search for Dataman Microdoctor Printer Paper, I've found a Dataman advert sold 10 rolls of
Thermal paper for £9.
https://worldradiohistory.com/hd2/ID...-Page-0081.pdf - Wasn't a bad price, but I hadn't thought output looked like thermal paper.
(I'm sure my keypad was more of a membrane, so maybe there was more than one version of it).
I also see it had a built-in disassembler for the various processors, that I'd forgot about - just to use up your paper rather faster!
I'm sure I had a range of 'conversion card' adaptors with it, but don't recall having alternative ROM's that's supplied with each of these.
These are the details copied from the OCR'd magazine-page advert:
BUS EXERCISER/DIAGNOSTIC AID
RAM and I/0.
Prints memory contents in HEX, ASCII or ASSEMBLER MNEMONICS.
Prints MEMORY MAP of addressing space. Performs CHECKSUMS. TESTS RAM, prints addresses and bits which default.
Tests data lines for SHORTS to rails, other data or address lines. Tells engineer of address/data faults impossible to find with other tools
Easy to program: retains sequences for testing up to fifteen different
products in permanent memory.
Microdoctor is supplied in Z80, 6500, 6800 and 8085 format with appropriate disassembler (say which you want). MICRODOCTOR £295.00
Conversion card & ROM (Changes configuration and disassembler e.g. Z80 to 6500 say which) £35.00
Clip-over PROBE only needed if uP is soldered -in) £35.00
10 Rolls Thermal Paper £9.00