atcomsystems.ca/forum Forums Other TDM Phone Systems 1A2 and Comkey Telephones & Systems Chaining 66 blocks with AMP connectors

A bit faster than swinging x-connect and the footprint of the KSU is a wee bit smaller too; however, the station cable remains the same.

I can give you a big thumbs up too 👍🏻

Nicely done!

Sam

> dude wrote on 03/02/18 05:19 PM:
> look at three way amphenol bridging adapters. cpc or pcp.

Ah, replying to this very late (>1year). Yes, those are a good solution actually.

I did buy one of these; found a "KS-19252 L1", C-P-C (Connector-Plug-Connector, or I suppose Female-Male-Female bridge/splitter) on ebay for about $30. Came in the original Amphenol box with paper documentation. Needed it for my Comkey416's, but works for 1A2 as well. A little hard to find in quantity though, but perhaps there's a commercial source. I like to think of them as a "Y-splitter" for 25PR Amphenol connectors, but I guess the correct term in this context is a "bridging adapter". Seems C-P-C is the most useful, since this allows one to have lots of M/F ended cables to layout a large system.

Even made a KS-19242 L1 webpage for the little device so I could link it into my Comkey416 docs, the page showing an all sides view of it, including the inside, and included a scan of the aging paper docs that came with it, along with some example wiring layouts for a KSU. Some pics from that page:

Make sure those phones are not 2564's, and not 2565's. The 65's have their violet pairs configured for a speakerphone, and bridging them together will cause odd problems with lights on phone 1 when phone 2 has buttons depressed, even if hung up.

Tom, I think you meant make sure that the phones ARE 2564's.

@TouchToneTommy.. oh, good point -- that's interesting. Looking at the wiring diagram for the 2565GK:



..I highlighted the violet pairs in violet and the signals they affect in cool blue.

I can see the violet pairs get involved with various important circuit paths (highlighted in blue), including all the T/R pairs on the phone side of the pickup keys (PU) on 23 (G-V) and 24 (BR-V), and through the dial button pad on 40 (V-G).

Looks like there's also stuff going on with the A leads and ground on 50 (V-S) and 25 (S-V) via the line switch and pickup keys.

At the head of 502-543-403, in section 2.05 it mentions this:


So I'm guessing those modifications to the inside of the 2565 phone sets might prevent problems with a C-P-C bridge?

Yup, Ed, you're right! it's been a while (a long while, like 30 years) since I ran into it

So this single board 1a2 KSU project continues to move along; I'm at revision H now (progressing through the alphabet). Thought I'd update with some pics related to these board's assembly process.

Regarding the large amount of cabling when interlinking two of these cards for a total of 8 phones, I found if I simply arrange the boards side by side, one board's connectors can act as a wire comb for the cables of the board above it, making for a nice clean/flat cable run for all 8 phone cables:




Here's what about $350 worth of press-fit amphenol connectors looks like from the supplier (there's actually two levels here, for a total of 40):



When you have that many connectors to mount, one has to get formal with the board assembly procedure.
Had to buy a small drill press to press-fit the Amphenol connectors onto the board, as it was getting to be a real problem to press them on just using a clamp and a jig. Here's a pic of the drill press with the two jigs used to press all those connectors onto the boards (I used 4 per board):



I put the board on the lower jig, put this onto the drill press, and then wind the drill press handles down so that the upper hardwood board presses the connector down onto the board.
Here's a closeup of the two jigs:



It takes a lot of pressure, which to be expected so they don't pop out when the phone connectors are connected/unconnected during use.

And here's 1 of the 2 boxes of relays 50 relays each ordered recently (4 of these relays are used per board), the two boxes together was about $400:

QUESTION: Aren't amphenol cables suppose to have 2-3 pounds of ty-wraps?

Sure wish those boards were available 30-40 years ago. Wouldn't have taken up a 4' x 8' backboard.

I think...since you are 'getting with the times', you shouldn't use the nomenclature of revision H, perhaps use rev 1.002 or 2.6b.

Good that you asked about the revisions.

Yes, I'd considered using #.## universally, but quickly stuck with letters for the boards for a few reasons:

Brevity for one, and to avoid confusion between board revisions and firmware versions, the latter uses #.## with optional letter suffixes.

For instance, it's entirely possible a single board rev (REV-H) can use a wide range of firmware versions, and vice versa.

So I specifically wanted to avoid having a situation like "v3.05 board with v1.37a firmware", as it'd get confusing quickly which number is which.

I did have use number suffixes on board revs a few times, as e.g. REV-G became REV-G1 when I caught a small problem in REV-G.

I'd thought about using model#s, like 1050, 1060, etc. which is how one would handle real products. And perhaps someday I might, once I get out of R&D, which I keep thinking is "this board for sure will be the final one!", lol. Which is exactly how I'm thinking now about the current REV-H.