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and very rarely ever needs repairs, once you fix them." - Dan/Panther

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Looking for BSPs on a WE 24B8 Busy lamp field

Started by Key2871, March 18, 2021, 03:37:28 AM

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Yes I've come across met sets before. But since I didn't know much about them, I just left them be.
I have seen sets like comkey and horizon that 25 pair cables. Or was I just smoking something I shouldnt have.
Around my area, 1A2 Comkey 416 were fairly common then came Merlin. Then other digital stuff of various makes.


Ok, some pictures of the unit, outside in.
The resistors that are probably for power the board looks cooked a tad, by the resistors look fine.
No end on the cable, and the panels on front and back are held by magnets. The front hold the line designation strips.
Kinda cool unit.



I was thinking the KSSM Volume 3 could help, But I don't have a copy and don't know if it covered these old parts... once you get into the 1A2 systems, you loose me... I flunked Electronics as a kid, so when it comes to these parts, I'm no help... anyway, you might look through the KSSM and the Specialty services manuals... I'm pretty sure these were made AFTER the bell breakup.... so ATT had the practices... check the TCI Library.... thats the only place I can think there would be help...


Hi Ken
You have a fairly simple circuit there.
It would not be too difficult to get some life out of it.
First, though, the two resistors in pic 14a, need to be replaced.
and prob that transistor too. they have burned.
Next, find the numbers on the chip tops, and use a ttl page to discover how they work.
Your circuit is a simple ttl circuit, so it will be a set of pull up/down resistors hanging on the input of a ttl gate, prob with a qualifier.
The gate opens/closes with either a voltage in, or a ground applied to the inputs.
And prob a blinker timer. pretty simple...for the most part.
once you find which package you have, the rest is following the inputs back to the cut cable.
You will find one wire going from the cable to a resistor, to the gate input.
This will repeat the same way for each input.
once you get power to the board, you can prob use a 5-12 volt power supply to drive each input to simulate the phone going on/off hook.


Thanks RB I knew it looked pretty simple, but the reason I got it was to use as a 1A2 station busy field.
So all I really need is the LED display with the resistors and then I'll  back track to what pin I need to apply I'm thinking a 5 volt source to illuminate the LED. Then I'll have to figure out how to best get the correct voltage from the 24 the KSU will send to operate the correct LED for that station.

John, KSSM in the 1A2 series vol 3 doesn't cover dimension sets at all. It does cover the comkey stuff.
In fact dimension has their own manuals for everything to connect the stations etc.
I believe there is a separate manual for programming.

In the conversation I had with the guy from ATT he worked for ATT and with a few other guys was working on a smaller system to replace the 1A2 stuff and use smaller cables and be user installable as well.

So these guys came up with the Merlin system, and he told me about the dimension system that was in use in some larger business where he was from.
And ATT wanted to phase out that as well for a smaller system again to get away from using the 25 pair cable because it was so expensive to make.
Plus they wanted it to be easily programmed from each station that was used.

Once they came up with the smaller 206, 408 and the I think the 810? Then they set out to design the larger Merlin plus system, and that also used the 4 pair cable.
And then it started as cat 5 cable and grew from that.

Now I worked for him a few years and learned he was quite a BS artist. But he and his wife were AT&T executive, she was a operator supervisor and she looked it. We called her stone face because she was all business all the time. Hardly smiled and was a hard Ass.
So I have no idea if what he told me was true or just made up with what he heard. But he too was sort of a collector.


Quote from: Key2871 on March 21, 2021, 10:08:25 AM
KSSM in the 1A2 series vol 3 doesn't cover dimension sets at all. It does cover the comkey stuff.
In fact dimension has their own manuals for everything to connect the stations etc.

Dimension was covered in BSP division 554-. A partial listing is in this index document:

Most of the info currently in the TCI Library is more general:

There's a copy of 554-010-110 here:
Visit:         WE  500  Design_Line



Thanks Paul. Your a wealth of information.
But John was saying he thought vol 3 of the BSP manuals for 1A2 systems covered dimension systems.
It only talks about Comkey systems and sets.
No dimension stuff in vol 3 1A2 manuals at all.
It might mention but I have looked through that manual over a month ago and there is no dimension stuff.


Darn it! This darned computer just lost my reply.... UHG! anyway, I downloaded the BSP for later reading... interesting stuff!


I knew a guy who worked for ma Bell, he had all sorts of manuals, you wouldn't believe what he had.
But he offered me a few dimension manuals, I declined as I wasn't into those, I was into the 1A2, he had the set of three and I got those for a steal.
I went to his house, and in his barn was a room off to the side, he had file cabinets full of nomenclature of all bell stuff, he had a 1E set manual hanging on the wall, along with a plethora of other sets. The 1E was practically NOS it was used in the co for checking the lines the co used those on.
I'm the barn were boxes and boxes of Comkey sets, and all sorts of stuff removed from service ocmver the years. But I guess he was too attracted to that stuff, because other things I got for diet cheap, that stuff was out of my price range. But I really enjoyed his stories and history he had filling each corner.
He even had a bit from a bit brace drill, with a electrical entrance cable it was fused to, he was drilling for a wire run in a house and hit the entrance cable, caught the house on fire... Oh boy that must have been a story for his supervisor. But he learned to check both sides of the sill before he drilled another hole.
RIP Dick. Glad to know you.


well, lets see if this reply works... anyway, I was trying to say that it seems we had VOIP even back in the 70's. Except it wasn't called that then... and computers....and Electronic telephones... todays VOIP phones are pretty much like what the dimension system was ages ago... a data set... anyway, its funny to look back on history and see stuff that we had versus what we have now.  how things have changed.... I was reading in the manual, that because of the technology limitations, you could only have so many sets on the system due to the memory limitations at the time, not to mention the limited data that could be sent.... how things have changed.... I remeber back in 1980 when I was taking a business machines class, they actually had a computer in the classroom.... what would life had been like had we had computers available to the masses back in to 1970's.... these systems were fancy! but, reserved for the large businesses... and what replaced these systems? or are they still in use today? interesting stuff, these "Electronic Telephones"  or, EKT's as they were called. this is an area I don't comprehend... at least unless someone explains it to me.... were these system driven by a computer? what OS was used? or was it all built into the circuit boards... I know IC's existed back then, but, how were they used in this setting?