Hi, Is anyone familiar with the "A-A1 Light Control Model for 1A2 Systems", made by the out-of-business TT Systems Corp? This is currently on eBay.

This device provides A-Lead control from station sets without the needed contacts. I'm looking for something that I can run multiple sets off of. There are 4 available on ebay for $50 ea (item number: 121209114950). Thanks for helping!

I never used that particular model. Depending on the unit you might be able to use one unit for each CO line, or you might need one unit per set.

Maybe someone else can chime in....


Sam

TT Products used to be located in Yonkers, NY and they supplied many different gadgets for the interconnect industry until they went out of business a few years ago.

www.Sandman.com has this product that does the same thing as the TT unit. Model # CID2N for $26.95 each.

There is no reason that you can't use one relay for multiple sets, because the accepted wisdom in these cases is that probably only one telephone, on each line, will be off-hook at one time.

If you just want the relay to activate the A-lead control in a 1A2 system, then you'll be OK. If, however, you want to take a line off HOLD that has been put there buy another user on the system, you'll be SOL unless you wire the T & R of the set(s) AHEAD OF the line card, rather than BEHIND it.

Refer to this thread for the explanation:

https://sundance-communications.com/forum/ubbthreads.php/topics/488492/A_Lead_control

If you can tell us what types of phones you want to use, there is more info that we need to share. For one thing, these simple devices (TT and Sandman) do not have slow-release relays, so using them with rotary sets will cause the 1A2 line lamps to blink when a single-line set is dialing.

If you plan to use conventional 500- or 2500-type sets, there is a method that allows you to convert the sets for A-lead control, and avoid the blinking and HOLD problems.

Thanks for taking the time to explain and share your knowledge! Additional information on the use is:

1. The single lines sets I want to use are 5 of the Bell System Design line series where there is no possibility of modifying the set for additional off-hook contacts.
2. The sets would be used by no more than one person at a time - this is in a residence.
3. All sets would be located less than 500 feet from the KSU.
4. If the KTU issue makes a difference, I have all the 400 series available (400D, G, & H) to use
5. All sets are home run wired - ideally the A-Lead controller is located at the KSU and the single line sets are wired from there.

Earlier I emailed Mike Sandman about his "HIGH SENSITIVITY LOOP SENSING RELAY" listed on his web site. He replied "The CID2N Modular Series Relay may work. You'd have to try it. $26.95 plus shipping. (The High Sensitivity model was discontinued.)

I wasn't sure if the TT Systems unit had field history on its reliability, since nothing came up when I googled it except that its Yonkers address was up for sale. Sandman's price is half the cost of the TT Systems on eBay.

OK, it sounds like you're OK if you use the Sandman units. One should be enough for all 5 phones. You can mount it at the KSU location, and create a multiple block that will feed all of your homeruns.

Are you sure that you can't convert the Design Line sets to A-lead control? I will admit I've never investigated that possibility. Do they really only have one set of contacts, or are you saying that there isn't access to the switch hook wiring? I thought that they had conventional Western Electric guts, which would imply a standard (500-type) switch hook contact arrangement. Is there a BSP you can consult to make absolutely sure? I'm not doubting your word, just curious.

https://wedophones.com/TheBellSystem/pdf/bsp/coquette/503-200-110-dec1975.pdf

This BSP for a typical Design Line set shows that the guts are typical 500-type and that it's possible to convert the set to A-lead control.

Paul Fassbender's comprehensive WE site:

https://paul-f.com/weDesignLine.html

has the BSP's listed for each Design Line set. "wedophones.com" has the BSP's in pdf form.

Maybe we can get you set up without needing the adapter...just sayin'.