Seiscor T-84A Phone Tester

[DavePEI]

I dug another item out from the treasure trove in the barn that came from Don Woodbury last fall. I know this was there, but just hadn't gotten around to doing anything with it, It is a Seiscor T-84 phone tester. I really didn't expect it to still work, but this morning, I got brave, plugged a phone into it, plugged it in, and lo and behold, it still does. Not that I have tested out all of its functions, but it will ring a phone, pass dial tone, check cords, etc. Still to be checked out is its dial speed and percent break functions, and a number of other less commonly needed functions. The only drawback to this instrument is its size - it is about two feet wide, probably over a foot tall, and a foot deep. I will do more testing  later today and make sure all functions work. Still looking for a manual for it, but chances of finding one may be very small, as it is very old.

I found an old BECO advertisement featuring the Seiscor T-84A. It states it will test for: loop current, 500 volt breakdown, rotary dial speed, rotary dial percent and break, transmitter and receiver output, normal ringer response, ringer connection, long loop ringer response, bell tap, tone dialing, and provision for continuity and noise testing for modular, Trimline handset, and cords. This model was for 20 cycle ringers, but there was a type 84R for harmonic, synchromonic, and decimonic ringers.

[rdelius]

That tester was the one I used at COT.It was from the ITT plant in Raleigh NC.It was slightly modified with the acoustic patrs removed. I put them back.

[DavePEI]

That tester was the one I used at COT.It was from the ITT plant in Raleigh NC.It was slightly modified with the acoustic parts removed. I put them back.

Do you remember how the dial speed test was performed. I will probably figure it out, but I haven't had a lot of time to play with it....  The rest of the tests I have pretty well tried, only didn't have a dial phone handy to try with it handy in the barn..

Just a matter of setting it for dial speed, and dialing 1 through 0? Same for checking % break?

Dave

[rdelius]

Just dial zero and the speed or break should fall in the black ranges. The number of pulses are counted and if wrong, the fail lamp will light.You might need to work on the push button assy. If I remember it needed work

[AE_Collector]

That tester was the one I used at COT.It was from the ITT plant in Raleigh NC.It was slightly modified with the acoustic patrs removed. I put them back.

Oh! You don't mean that you used a tester of this model when you were at COT....you mean that you used THIS tester when you were at COT!  Cool!

Terry

[DavePEI]

Just dial zero and the speed or break should fall in the black ranges. The number of pulses are counted and if wrong, the fail lamp will light.You might need to work on the push button assy. If I remember it needed work

Hi Robby:

I also echo Terry's comment! The only externally damaged switch I can see it the TT switch on the far right. But some of the other switches are sticky. It works, but is missing its outside plexiglass lens.

The main fuse which I believe was originally on the front panel was removed, and an inline clip type fuse holder was relocated inside the cabinet and taped in place. As I do have several of the correct type fuse holder, I will replace it and return it to the front panel.. I must try out the dial tests. Not that I don't have any dial type phones in the barn, but none of the ones I had handy had cords... So I quickly tested it using a 2500 I had handy there. Too lazy to go into the Museum to get one of my many dial sets.

I notice there is an Amphenol cord and connector coming out the back. It appeared on a quick glance to be connected to the row of LEDs close to the top of the panel. What was this for? I thought the set was for single line phones only....

Incredible it was the exact same one you used! It quite likely is, then, as Don bought out Chicago Old Telephones, and this stuff came from Don.

Dave

[andre_janew]

In the picture, I see a touch tone phone hooked up to the tester.  Is it made for testing such phones? 

[DavePEI]

In the picture, I see a touch tone phone hooked up to the tester.  Is it made for testing such phones?

It will do most tests on a Touch Tone phone, but not tone accuracy. Al speech tests, ring test, etc. it will do. Robbie could give more information here, since he used the exact same unit when he was with COT.

The only reason it is shown with a TT phone, is it was the handiest phone I had in the barn when I dug it out, and I was able to check most of the tester's functions with it. I was to darn lazy to go over to the Museum to get one of my good dial phones. I had lots of dial phones in boxes in the barn, but none I could get at easily which had line cords 

Dave

[rdelius]

I do not think it tested tone sets.It might have needed repair or a card was missing.All we sold were rotary sets.There was a manual for the set or the older  version T-84.when they were sold.The ring button lens was missing when I got it from ITT so I switched the T Tone lens for the missing Ring one
.Cut a piece of plastic to put on the tone button and put a hand written ring label  to replace the ring button. Make sure fuse holder in installed or intact .It was damaged and clean out the oil resudue in the bottom.I will check to see if I have the manual

[DavePEI]

I do not think it tested tone sets.It might have needed repair or a card was missing.All we sold were rotary sets.There was a manual for the set or the older  version T-84.when they were sold.The ring button lens was missing when I got it from ITT so I switched the T Tone lens for the missing Ring one
.Cut a piece of plastic to put on the tone button and put a hand written ring label  to replace the ring button. Make sure fuse holder in installed or intact .It was damaged and clean out the oil resudue in the bottom.I will check to see if I have the manual

Hi Robbie:

Well, the fuse holder was missing, but someone at some point put an inline holder inside the cabinet, but I am going to replace it and return it to the normal type, as it is only the clip type holder and could short against the case.

Unless i am very mistaken, the right hand button says TT, but doesn't appear to do anything. What I am curious about is the cord and amphenol jack which runs out the back. It appears to be connected to the line of LEDS close to the top, but I haven't really looked at that part of the circuit closely. If I could find a manual, I could likely repair the TT part of the circuit if I can find a schematic for it - the boards all appear to be there - at least no empty board sockets inside. But, I so far have been unable to find a manual for this early model. Most I have been able to find are people who have the version with the upright acoustic coupler, though I don't know it there would be any circuit changes made after that.. It would be nice to find the exact manual for it, though, or any manual, for that matter.

I may use this unit in the barn as I sort through the phones and stuff which came down from Don last year, and keep the mess in the barn as I triage the stuff there. I do also have the B&K 1045 I use in the Museum workshop. I gave my old RS tester away some time ago to Terry.

There doesn't seem to be any question that this was indeed the same unit that you worked with - yes, there is a handwritten ID on the ring button as you said! What an incredible coincidence!

Also, Robbie - Here are a couple of photos of the pushbuttons and the black block with LEDs below - what was the block for? Is that for testing spade cords, or at least half modular cords? In other words, plug the modular end into the line jack then insert the spade ends into the appropriate colored slot in the block, and if good, the LED above the wire will light? I haven't tried this, so just guessing.

Dave

[rdelius]

I assumed that the block was for spaded cords but I never used it. I think the colored dots were just that and did not light.you could test trimline cords though.

[DavePEI]

Hi Robbie:

Thanks. I was thinking that afterwards it was far too early for anything but red and green LEDs. However, I think the dots represented the wire color which corresponded with the ring, tip, ground, etc., and is so, one could use it do diagnose crossed pairs in a half modular cord.

I dug up a new fuse holder for it, but will have to ream out the old hole slightly to get it to fit.

I wil need to find a manual, or at least a schematic for it before I diagnose the problem with the TT circuit - I did remove all boards today and visually inspect them; all are there, and none show any obvious signs of failure. However, the TT Button doesn't appear to do anything more than light when depressed.

Any idea about the cord with an Amphenol connector on the back (what it was used for - it is perfect fit for that on a multi-line set, but  thought these were made for single line??

Dave

I assumed that the block was for spaded cords but I never used it. I think the colored dots were just that and did not light.you could test trimline cords though.

[rdelius]

I never tried the Amphonal connector.This tester was owned by ITT and might have been modified.I un modified some things to get it working to replace an older t-84 set

[DavePEI]

I never tried the Amphonal connector.This tester was owned by ITT and might have been modified.I un modified some things to get it working to replace an older t-84 set

Thanks! I think that I have found someone with a manual, and he is scanning it for me. When I get it, I will have a PDF copy available... I got the new fuse holder in, but ran out of time and didn't get it wired today. It is awkward, as the lip of the case gets in the way of soldering it, so I think I will pre-attach two wires to the holder, tighten it in, then splice the new wires to the old with solder, then heat shrink tubing.

Dave

[DavePEI]

I now have the following three manuals for this unit, thanks to Jeremy Walters.....

Seiscor_T84_Calibration.PDF
Seiscor_T84_T84R_Op_Manual_i_1.PDF
Seiscor_T84_T84R_Op_Manual_i_2.PDF

They will certainly answer some of the questions i had about the unit.

The manuals date the production of this unit to sometime in 1977 or 1978, after which they produced other variations of the set. This manual is for exactly this version of the set.

Dave