clocking off disabled T1

[coniglio]

I had an T1 card w/ clock controller daughterboard card for AT&T T1. We installed new MCI T1 card but left daughterboard on AT&T T1, as the MCI T1 was running concurrently w/AT&T T1. (so two T1 cards, installed, cc card stayed on AT&T T1 card.). Per our request, AT&T disconnected their circuit after we ported our #s over to MCI's T1. Once they did that, the MCI T1 kept running errors and disabling. Our maintenance vendor got the alarms and dispatched a tech who said that because the daughterboard was still on AT&T T1 card and AT&T disco'd the circuit the MCI clock was in free-run and the cc card needed to be moved to the MCI circuit(which we did last night).However, vendor contracted to do original job says even if AT&T discod circuit that should have no effect on MCI T1 running framing errors. (eventually tech was going to go back and remove AT&T T1 card and put cc on MCI T1 card). I need to know which tech is correct, as I don't want to have same problem in subsequent locations. Thank you.

 

[johnpoole]

you can't clock off of a disconnected t1..your not getting battery let alone clock pulse. move it, and change your clock ref in 73. then in 60 trk pck, to get it off free run. your switch needs to clock off of something, freerun works great if you don't have t's

john poole
bellsouth business
columbia,sc

 

[coniglio]

i can't do any of this, as I simply don't know enough about T1s, but since tech did move cc card last night I am going to hope he did this. I'll try and figure it out w/NTP. thanks.

 

[johnpoole]

ld 73
REQ prt
TYPE ddb

PREF 3
SREF 17
ld 60
ssck 0

trk pck

ssck 0

that's pretty much it, let me know if i can help, i don't run down vendors but did he say you can track off of a dead t1?.. that might make me nervous


john poole
bellsouth business
columbia,sc

 

[coniglio]

Well, original tech is supposed to be pretty good and the other tech who went out there last night happened to know original tech and also said he's one of the best tech he knows...thank you for your post. I cannot begin to tell you how much i've learned from tek-tips. So the fact that old T1 card w/cc is still in slot in PBX is irrelevant if carrier disco'd it?

 

[johnpoole]

yes it is dead, then i must have misread your post, let me knowif i can help any further

john poole
bellsouth business
columbia,sc

 

[coniglio]

i don't think you misread it. What part do you think you misread? old T1 w/ cc is still in PBX but carrier disco'd circuit and new tech who was dispatched said that's why T1 kept going down, because cc card was still on disco'd T1.

 

[johnpoole]

i thought i read that the tech stated that you could clock off of a disco'ed t1

john poole
bellsouth business
columbia,sc

 

[coniglio]

The first tech did. The second tech who went to site yesterday for unrelated issue noticed the cc card and brought it to my attention, as the circuit had dropped twice the night before. When I asked first (original) tech he seemed to feel that even if AT&T disco'd circuit MCI T1 could still clock off AT&T T1 card that still had cc on it. Anyway, cc card is now on MCI T1 card and all is well. thanks for your help and i'm going to look at LD 73 just to better understand all this.

 

[McGruff753]

Okay I have a question here on this. Do I need a second daughter board for a second clocking source? Here is my printout:

CC0 1
PREF CC0 1
SREF CC0 FREE RUN

TRSH 01
RALM 128
BIPC 0
LFAC 0
BIPV 4 3
SRTK 24 3600
SRNT 1024 1024
LFAL 17 511
SRIM 1
SRMM 2
ICS

Loop 1 is Sprint local area and Loop 3 is MCI long distance. We lost our DS3 a while back and the PBX kept crashing due to Slipp Errors. Our vendor moved the daughterboard to Loop 1 from Loop 3 but I see the second source is free run. Can I still use the DS3 as a secondary clock source without another daughterboard?

 

[johnpoole]

yes if you want a second clock from the world you'll need a clk on that card.. you don't need one, use the sec choice as free run.. that clocks internal. not usually a problem but may cause slips.. ie..start of frame from source is not in sync with your rec side. i have seen 2 and 3 year old switch with the clock source not set.. i always use my ld carrier for a clock. the local carrier clocks off of ld routes to the next office

john poole
bellsouth business
columbia,sc

 

[McGruff753]

Yeah, the problem we had was the darn thing would slipp so much, the calls were dropped after about 30 seconds while the loop reset itself. So I guess I need to price another daughterboard for this thing then cause Free Run is not stable enough.

 

[dixiedogger]

you cannot have another clock card in a 11 system. It only supports one card unless you are using ip cabnits. then you can have 1 in each cabnit. You can still define the secondary reference if the primary goes down it reached accross the backplane to the other t for the clock.

 

[McGruff753]

Cool. So with Loop 1 being Sprint and Loop 3 being MCI, would my programming need to look like this compared to above?

CC0 1
PREF CC0 1
SREF CC0 3

TRSH 01
RALM 128
BIPC 0
LFAC 0
BIPV 4 3
SRTK 24 3600
SRNT 1024 1024
LFAL 17 511
SRIM 1
SRMM 2
ICS

 

[johnpoole]

that is the setup i would use in my 81, trck pck in 60 will lock it to your pref. didn't know you couldn't add a cc to a loop and still ref it in clock ddb, but i don't get to play with 11's much. you can ref off of any t1 in a larger switch but it needs a clk cable in and out

john poole
bellsouth business
columbia,sc

 

[hawks]

McGruff you are fine the way you have it set up assuming sprint is your primary clock source. The clock card uses the back plane of the system to go to your secondary T1 for clocking if needed. So as long as the T1 with the clock controller is in the system and has power you can clock from either span.

 

[McGruff753]

Woo Hoo. Thanks guys.