A Toshiba DK280 PABX system I'm supporting was delivered & installed 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 repaining 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 show 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 year.
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 ssytem 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.