Novelty "Retro" Cell Phone Handset in an Acoustic Coupler?

I have a similar, but rather older (:-)) device on my bench. A 'Telephone Network Simulator' made by 'Telephone Analysis Systems'. It's a 3U high rack unit, packed with electronics (there must be over 300 ICs in there [1]) it does what you describe. It has 2 telephone line sockets to which you can assign telephone numbers, you can then dial one from the other. You can configure it to give the dialing, ringing, etc, tones for just about any national telephone network (so you can make sure your modem will correctly work, say, on the real French network), you can set the ringing single frequency, votlage ,on/off times, etc. And the line current. It iwll monitor the signal levels in both directions, it will let you degrade the signal (add noise, etc) to see how that messes things up. Mine is the base model, it only lets you degrade the signal in one direction at ta time. I has both RS232 and GPIB ibnerfaces on the back, so far I've not figured out how to talk to it, what the commands are, etc. Docuemtnatio nfo said device does not seem to exist :-( [1] Inclduing 6 microprocessors/microcontrollers. An 8085 to control the whole thing. Anotehr 8085 to control the telephone lines. An 8049 to do tone generation. An 8041 to run the VF display. Yet aonter 8085 to boot the SSP. adn a TMS320 DSP to handle signal degredation, etc. Why do I ahve it? Well, I wanted something to interconenct a pair of dial-up modems, much for the reasons you suggested. I sketched out a simple design (state machine, line control relays, etc) and found t omake it -- includign the PSU bits, etc, would cost as much as a cheap uniut on Ebay. Of course the latter owuld probaly not last as long, and would be a lot harder to repair. And then I saw this thing on E-bay, described as non-working. For $25 (+4 times as much to ship it), it was the cheapest. And even if I couldn't fix it, I guessed there would be useful bits inside, like the PSU. Well. after re-assembling it correctly and repairing the pwoer switch (which had been mangled by the wrong screws beign removed first), it would power up but fail the self-test. Re-seatign al lteh socketed ICs got it to past the tests, but it didn't work. Replacing a couple of ICs on the line interface board got it going. I then had to replace the backup battery (used to store the user configurations, nothing too important) and make up various cable adapters. Oh yes, it wil lalso simualute 2 and 4 wire privae lines, if you need to test that flavour of modem. In a sense it's total overkill for what I _need_,one of the simpler modern units would be fine. I don't need signal degredation, the ability to add external balance networks, , the ability to generate the correct tones and rignign signal for various countries, etc. But it's a nice unit, and I guess I also collect classic test gear. -tony