sundance-communications.com/forum Forums Other TDM Phone Systems 1A2 and Comkey Telephones & Systems Looking for a tech to install my 1A2 515

Thanks Art, thats why I mentioned the flashing light speeds in hopes he could learn the difference.

Is there a compatibility chart for 400 units? Mix and match allowed, not allowed, features etc.

I looked on ebay and saw a lot of 400's for sale and remember when we were told to try and match the 400's on an install or at least keep them within a couple of letters of each other.


Thanks,
John O

All 400-types (and the SanBar 4000-types) are compatible. You should not dwell on the KTU's. They are not your problem.

You need to understand what happens before and after the KTU, and how the telephone itself works. These are not things that can easily be typed, as you are asking for an entire lesson in 1A2 key telephony.

Instead, do what the other people have recommended: Get a traditional (non Logic) key set and plug it in. Then, if you get troubles, use your butt set and trace out where the failure is.

1. System idle. Using a butt set, see if there is dial tone on the COT & COR. If no, trouble shoot dial tone to the KSU. If yes, go off hook. Can you break dial tone? If no, trouble shoot dial tone source. If yes, proceed on to 2.

2. System idle. Using butt set, see if there is dial tone on the T&R set side. If no, replace 400 KTU. If yes, go on to 3.

3. Set up an incoming call to KSU. Using the butt set, see if there is ringing on COT & COR? If no, trouble shoot incoming line for ringing problem. If yes, go off hook. Can you stop ringing and establish a talk path? If no, trouble shoot incoming line. If yes, go on to 4.

4. Remove all set side wiring from T&R, A, A1 L and LG of the KTU under test.

4a. Set up an incoming call to KSU. Using butt set, see if there is ringing on T&R set side. Go off hook. Short A and A1 of the line being tested. Maintain short. Did the ringing stop and do you have a talk path? If no, trouble shoot wiring and KTU. If yes, KTU and incoming line are working properly.

5. Connect set side wiring to T&R, A, A1, L and LG of KTU being tested. Repeat 4a. If no, trouble shoot set side wiring. If yes, trouble shoot connected phone. When 4a is being done, you should see a visual indication on the connected phone. The flashing lamp will turn solid.

Rcaman