Interfaker 4 RS232 test set

[Andrew Mawson]

A bit OT, but I know that there are several here who have worked in the comms environment for some years !

Has anyone any technical information on the Interfaker 4 MT25-IV from Modular Technology? I've just revived one that the previous owner had left the batteries in for years and corrosion was rampant. I was quite surprised how much electronics was inside hence the question. I've been using a different RS232 signal patch / monitor for years that has no electronics in it at all.

Nice unit but it's also be nice to know a bit more about it. (I've a Tektonix 834 for analysing more complex issues, but this Interfaker must have more capabilites than at first meet the eye.)

Andrew

[Andy Burns]

I thought it was just a 25pin to 25pin breakout with the usual LEDs, DIP switches and jumper wires? My Componodex Miniscope seems to have been trampled by an elephant ...

[Andrew Mawson]

Yes so did I - it has quite a few ic's - possibly they are just buffers to avoid loading - not easy to see what they are due to the sandwich construction. The Interfaker 3 took a 9 volt battery, and this Interfaker 4 takes three AA cells giving 4.5 v so another possibility is it has a charge pump inverter to generate +- 9 volts. Nicely made kit.

Andrew

[Brian Gaff]

Trampled? Perhaps you had it connected to a phone line while making a trunk call? Brian

[AnthonyL]

Maybe it's got the intelligence to auto join up two "randomly" connected RS232 devices rather than leaving it to the operator to work out what I recall was sometimes a bit of a black art?

[John Rumm]

I have a feeling I have used one a long time ago... I don't think they were particularly smart. Probably just had the ability to generate their own RS232 voltage levels (using a Max232 or similar device), and perhaps using battery power to illuminated the LEDs rather than line power.

[Andrew Mawson]

I think that you are right John - no intelligence as such just power generation and buffering. I used to use one and others of a similar ilk back in the 70's and early 80's but only as a temporary patch panel and monitor to prove handshaking and making up a final cable to the same spec. I think that the Interfaker was the one others tried to copy at a lower price as they were stupidly expensive even then.

Andrew

[John Rumm]

Indeed... I still have a couple of RS232 boxes - one with lights, another with switches and patch wires. Have not used them for years though.

I think the last time I used them was for working out the (very unorthodox) handshaking used by a HP7475 plotter so I could make a lead that would drive it.

[Andrew Mawson]

I'm still using RS232 to talk to three CNC machines I play with in my home workshop. (Beaver Partsmaster CNC mill, Traub 5 axis CNC lathe, and a Fanuc Tapemaster CNC Wirec EDM machine) I even have one with paper tape input (the Fanuc), and also have a paper tape reader / reperforator which itself has an RS232 interface.

Old technology rules :)

Andrew

[Chris Bartram]

That takes me back. I don't remember it being terribly complicated, a breakout with indicators and the option to pull lines high/low? It's been a while though.

[Bob Eager]

I have three UPS units that are monitored/controlled via RS232. Not to mention three VAXes and a PDP-11 or three.

[John Rumm]

I think I am down to a US Robotics sportster, and that is about it... Oh and a Wacom tablet that I am still trying to get to play nice with x64 windows.

[Andrew Gabriel]

I used to use them a lot when designing/building X.25 packet switches at GEC, 30 years ago. They didn't have a long life when constantly being connected/disconnected from 25-way D-type connectors - the connectors would fail after around a year's use. I took a couple of dead ones home and mended them, and still have them somewhere (although I couldn't find them when having a quick glance around just now). Mine are an earlier model than yours.

They buffer the signals so they aren't loading the lines. When used with clocked links (such as X.25), ISTR they also detect clocks on the clock lines and show them more inteligently than just red and green flashing too fast to see.

[Huge]

I have a big box of null modems, assorted adaptors, male-female adaptors,

25-5 way adaptors, A/B switches and the like which anyone is welcome to if they're prepared to come and get them.

[Andrew Gabriel]

Several components of my home automation use RS232 - interfaces to thermometers and thermostats, aircon, alarm, etc. Also some RS485 multi-drop.

[Huge]

[15 lines snipped]

This thread reminded me that Ubuntu (& hence Mint) have fixed the bug in udev that stopped the USB/RS232 dongle I have getting the correct permissions in /dev and hence stopped NUT from running properly & monitoring my RS232-only APC SmartUPS 2200.

So, I got halfway through installing NUT before I remembered that the UPS is broken. (Needs new batteries.)

Thanks, guys.

[Vir Campestris]

Several black artists here on this newsgroup!

The one I used to use had a PP3 battery. Suspect it was an Interfaker II

- but it was a while ago...

Andy

[p.lad.work]

Hello I would like to know how to remove the batteries out of the interfaced. I've turned the end using 1/2p coin but cannot get the cover to eject.

Thanks

[Brian Gaff (Sofa)]

Bit vague that message. Angle grinder? grin. Brian

[Paul]

The discoloration at the bottom of the hinge, hints at where the batteries hide. 3xAA battery of some sort.

Paul