Thanks, i'll try all that. I must admit I don't fully understand what the REX# does, as I've only use it to make backups of the RAM, but it's features go way beyond that, so it's unclear to me if - for example - the tsdos that comes with would be "US minded".
>From what I understand, the original owner (which may even be in this list) had to replace the belgian/european ROM with another ROM, most likely a US one, to be able to use the REX# ( that's what I got from what he told me, don't quote me on this ) All these changes could, maybe, break my modem. However i've been looking at the schematics of the modem part and all of this is as simple as can be, it's really purely analog in many areas, and there is no way on earth any of this is software controller. I mean : the thing doesn't care if the dial tone is 440, 600 Hz or anything (at least looking at the hardware I see no way this would be measured, even less handled by software) So if I take for granted my M102 is a Belgian.european one (it' has the sticker of the telco!), I guess the electronics where adapted to our particular voltages. What could be a possibility if that some of these are now out of spec One final comment ; if I hit F4 (TERM) in TELCOM, the M102 starts to emit an awful noise (like if it was connected to a data line !) it does that even when the M102 is not connected to anything ( I mean, no wire connected to it at all) It is also, afaics, completely crashed (i have to reset/reboot) Is that "normal" ? That would point to a problem with ROM/REX... thanks again for taking the time to help weirdo that wants his analog modem to work :) Le jeu. 3 févr. 2022 à 23:32, Brian K. White <b.kenyo...@gmail.com> a écrit : > I can tell you one thing for sure, the REX has no effect on the modem. > > But you can prove that to yourself by just removing it. It doesn't hurt > anything and it won't even lose it's programming. Just pop it out, and > see that it made no difference. > > Have you tested the line with a plain analog telephone? > > Have you verified the modem cable doesn't have a broken wire? > > Since you are talking about dialing vs answering, is the the ANS-ORIG > switch in the ORIG position? (Answer vs Originate) > > Measure the voltage between tip & ring when the the modem is on-hook. It > should be 48vdc > > Measure the current on either tip or ring when the modem is off-hook. It > should be about 20ma, at around 9vdc (actually a wide range from 3 to 12) >
