sundance-communications.com/forum Forums TDM Business Telephone Systems Comdial Telephones & Systems DX-120 T1 Glare

I installed a T1 about a year ago and the customer just now mentioned this to me saying they have been disappointed in having to deal with this, what we would call "glare".

When they are part way through dialing a number and an incoming call comes in, they are connected to the caller. This happens for both phone set for incoming ring and not set for incoming ring.

They are not dialing 9 for an outside line, they simply press a line key (817, 818, 819, etc).

In case this makes a difference, the Dial Wait and Dial Delay are at default settings of zero and 100 mS, and Call Completion set for 10 seconds.

This gives the *appearance* (but not a conclusion or explanation) that they are hearing an artificial dial tone generated by the DX-120 or by the T1, that really isn't an outside line dial tone. So when a call comes in, they are dropped into that call.

Any thoughts?

Verify your hunting opposite of the other end when selecting trunks. Changing to GS trunks will also correct this, but you still want to hunt opposite of the far end.

Probably they are actually being connected at the exact same time they are pushing the line key, not after they have seized dial tone and started dialing. Once dial tone is actually seized the CO marks the trunk as busy and will not pass a call through that channel.

If in fact this is really happening then the CO has some sort of issue. If dial tone is being provided by a soft switch there is a possibility that the SS is cutting off the initiating call before it is completed and handing the system the incoming call. I heard of this a few months ago from one of our other vendors here in town that had a Toshiba behind a dynamic SS.

Like Justbill mentioned I would change over to ground start but some of the SS dial tone providers go spastic when you mention ground start. They've never heard of such a thing.

I would ask your customer to make sure they are actually hearing dial tone before they start dialing. Whatever the issue is, it's not the DX-120.

JustBill -
I can see where using GS might fool the T1 into busying out the line. But they aren't under a dial 9 access, they are pressing the line key associated with the particular T1 channel/line.

Deltron -
"Probably they are actually being connected at the exact same time they are pushing the line key, not after they have seized dial tone and started dialing." - This is happening so frequently, I can't imagine that many people dialing before they don't hear a dial tone (yes, it can happen with perhaps a few power users, but I don't think this is the case). Nevertheless, that's why I have the Dial Wait set to zero.

"Once dial tone is actually seized the CO marks the trunk as busy" - is what I would expect to happen, but for some reason it isn't.

When I was referring to "artificial dial tone", I should have described it as a soft switch dial tone generated by the DX-120, unless the SS is actually coming from the telco. I'll try GS and see what happens.

I didn't read your whole post, my fault. I guess if there is a reason they feel they need to direct access the lines then they will have to be trained to pick up the lines in reverse order of the incoming hunt. I don't know your system, I was just talking trunking in general. You could always designate a set number of trunks for outgoing only also.

By that logic, any key system user would have to be trained to do that. I've never heard of key system users express that complaint as being a serious problem.

I'll try to duplicate the problem tomorrow.

Sorry was just trying to explain how to get rid of glare problems they way I've seen the problems corrected in the past. Maybe this system is different than others I've seen.

I don't think the call is coming in after they start to dial, I think that is when they realize the incoming call is there. If so then as Deltron stated the CO has an issue.
Why would anyone with a T-1 be pressing line keys instead of dialing 9? :shrug:

I was wondering the same thing, Larry. What was their reasoning behind wanting to use it this way?

Justin

CMDL_GUY -
"I think that is when they realize the incoming call is there" - You may be right. I don't know how many of the sixteen users have complained, but considering that only three are set to ring on incoming calls...I bet what might be happening they are pressing a line key just as a call comes in. But still, why has this come a problem for my customer with so many other key systems in use today.

"Why would anyone with a T-1 be pressing line keys instead of dialing 9?" - They had POTS lines in the past, so I wanted to "preserve the dialing experience" [don't laugh]