think it's a phone cabinet?

[raberding]

Hi - my son recently bought a 1928-ish home in Toledo. Wondering what this is. Phone is my best guess. I have not been there yet - will investigate further in a couple weeks.
Any thoughts?

 

[LarryFine]

Yes, definitely phone. The bar on the left with the terminals is a lightning arrestor.

 

[hbiss]

Yes, it's phone. 16 pair terminal. There was an old multi-line key system installed at one time. Very, very old but the new UR splices make me believe some of the wiring may be still in use. Do with it as you will.

No, no lightning arrester. That's merely a "splice" like we use the punch down blocks for today.

-Hal

 

[tortuga]

Definitely some type of phone, I agree with Hal it does look like a lighting arrestor but is not, but but I'd say its a part of 'key 1A' home phone system.

 

[zbang]

Not "1A' phone system, not an arrestor (no obvious replaceable parts), just a terminal block. If I went digging, I could probably find the part number.

 

[tortuga]

I am pretty sure its a 1A system, there is a fellow sparky near me that collects them.
he shows off his 1A system in this video you can see the terminal can @5min

 

[LarryFine]

Oops. I thought one of the top wires was a ground lead.

 

[zbang]

If it's part of a 1A, where's the KSU (relay box). Could be terminals for a key system, but it's still just the terminals.

 

[tortuga]

If it's part of a 1A, where's the KSU (relay box). Could be terminals for a key system, but it's still just the terminals.

Yeah its just the terminals, I'd look around for the rest of the system see if its still there, probably long gone.

 

[raberding]

thanks all!
Might be some more vintage electrical items yet to be discovered

 

[OldBroadcastTech]

1A2 systems used 25 pairs for up to 8 instruments, 3 pairs per device.

I think.........as I recall , it was 1970 when I learned this:

T, R for the talk circuit
A was ground
A1 was lifted from ground to put a line on hold
I for the 'intercom' buzzer
L to light up the in-use line

We used to punch the 'INT' button then dial 1 over and over as fast as possible and listen to the phones give the 'intercom buzz' all the way down the hall..........

 

[hbiss]

The 3 pairs

T
R
A
A1
LG
L

Tip & Ring= talk path
A & A1= A lead control
LG & L = lamp ground and lamp

1A2 systems used 25 pairs for up to 8 instruments, 3 pairs per device.

1A2 could support hundreds of stations and hundreds of lines. But when you need that capacity you go to a PBX instead.

-Hal

 

[LarryFine]

But when you need that capacity you go to a PBX instead.

Isn't that a motorcycle?

 

[OldBroadcastTech]

Thanks Hal

I knew I had something wrong.........

 

[zbang]

Typical (2)565 set (aka "six button" had five lines using three pairs each plus another for the ringer and some spares, the last five pair of the twenty five were designated for a speakerphone. If you had the ten button set (2580?) the A1 leads were re-purposed as A leads for other lines. (That's all from memory, I'm not going to dig out the BSPs at the moment.)

1A2 could support hundreds of stations and hundreds of lines

My first full-time employer* had a 1A2 system with somewhere north of 300 automatic-ringing private lines, spread over 4(!!) 90-button Call Directors and a bunch of 18 and 30 button Call Directors. (The 90 was three 30's in one chassis.) Those sets wired to concentrater KTUs to mux the control lines. One of the projects while I was there was building a replacement switch for the whole 1A2 system; off-the-shelf systems were far to expensive for what we needed.
*Kastle Systems, Arlington VA (late 70's early 80's)

 

[hbiss]

One of the projects while I was there was building a replacement switch for the whole 1A2 system

Were you successful? What did you use?

-Hal

 

[zbang]

IIRC, it was a stack of Candela concentrators terminating the PLs and some POTS lines with field-end dialers, then keypad terminals at the desks. Everything was held together with some custom code on top of the company's existing embedded OS which hooked into existing data (all on PDP-11's). The early versions worked well enough to continue development, I left the project, then the company, somewhere in there.

The basic problem was having the reverse number of ports of a PBX- lots of line ports (>300), few station ports (<30); converting all the lines and field hardware was cost-prohibitive at the time.

And as time went on and telephone tech improved, those private lines started to be replaced anyway.

 

[hbiss]

PDP-11's

And as time went on and telephone tech improved, those private lines started to be replaced anyway.

Yeah, that was the time where if you blinked they had something new. The Merlin, the first all electronic key system was being installed by AT&T to replace the 1A2. Instead of running 25pr (and multiples of) all over, all it used was 4pr. Thus was borne the RJ-45 and the 568A WECO standard.

-Hal

 

[zbang]

Ah yes, the Merlin. On the one hand, it did the job and was easier to wire. OTOH, the wall-to-set cables supplied later looked like Ethernet patch cables but were 8c in a jacket, no twisting/etc; needless to say, they did not work like an Ethernet cable .

There was definitely something new almost every month, for which we can thank Divestiture opening up the markets.

 

[hbiss]

the wall-to-set cables supplied later looked like Ethernet patch cables but were 8c in a jacket, no twisting/etc; needless to say, they did not work like an Ethernet cable

Still have a few left. The old Merlin is pretty much extinct but if you wanted to be historically correct you would want to use those original gray line cords. Whenever I saw a patch cord being used I would know some computer guy or DIY was playing with it.

-Hal