TELECOM Digest OnLine - Sorted: Help: Hookflash and Ground Start Analog CO Trunks From PABX

Help: Hookflash and Ground Start Analog CO Trunks From PABX

John Bartley (
Wed, 02 Mar 2005 13:37:59 -0800

"Help me Obi-Wan Kenobi, you're my only hope."

A Toshiba DK280 system I'm supporting was delivered in 1994, and then
configured for loop start CO POTS lines into a Centrex in liew of
more exotic trunking arrangements. It has four (4) Toshiba RGLU
four-port line cards.

Recently, we changed seven of the 16 CO lines, (which are all part of
a hunt group to answer calls dialed into one number, and to make
outbound calls), from loop start to ground start, to solve a problem
with the lines being reseized, and the phone desk operator getting
loud 120ipm reorder tones in her ear.

So, we changed seven of those lines from loop start to ground start.
That solved the reorder tone problem.

Since then, however, the Toshiba RGLU cards for those seven lines
won't send a hookflash to the CO trunk when a user does a hookflash
from a deskset. If the user, on the same phone, hookflashes on one of
the nine remaining loop start lines, the hookflash passes OK.

Swapping cards does not solve the problem; the cards pass a hookflash
OK if they're configured for loop start, but fail as ground start.
Other cards which work OK as loop start fail when reconfigured as
ground start. Both s how the cards have not failed, but instead
poiunt to a design defect.

Toshiba's techs, after three calls in which they denied any problem,
on the fourth call advised our local dealer supporting the DK280
that, well, yes, there _is_ a problem, they've known about it for
some time, and we should buy the Version 3 PKDU cards which will
solve the problem.

I think it's the best use of taxpayer $$ to stretch this system out
another year until our new facility and its new system is ready, for
it really is quite useful. Except for the one problem we have, it's
perfectly servicable , and we don't have funding to replace it this

It's my recollection that the use of hookflash signalling, opening the
tip-ring connection on the CO line, even for ground-start lines, is
decades old , yet the local Toshiba dealer (which shall remain
nameless) has a repair clerk who's asserting that is was *not* a
standard in 1994 when the sytem was delivered.

I want to build a case for hookflash on ground start lines being a
normal practice, something any line card sold for ground start use
should be able to do when sold, even back in '94.

May I ask the collected wisdom here for help?

Ideally, I need sources predating September 1994 (Bellcore manuals,
FCC Part 68 regs & rulings, et al.), should you know or have them,
which I could then wave under the noses of the local rep as well as
Toshiba's gummint rep. , to encourage them to replace the defectively
designed cards at no additional cost, as those cards were not fit for
the duty Toshiba represented them to be fit for.

Thank you kindly, all. Replies, if you please, either to the list, or
that's impractical, to K7AAY [at} ARRL {daht] NET instead of the spam
trap address from which this is posted.

John Bartley, K7AAY, USBC/DO, PDX OR, USA
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