seeburg L100 selctions missing!

Hi All,
I have a selection problem with a Seeburg L100 and know very little about Seeburgs so hoping someone can help.
There are 5 selections that won't register, they are all along the Six row (Bsides) and alternate
The numbers are B6 D6 F6 H6 K6
I have checked the wirng on the button bank and button bank plug that goes on edge connector, inside the tormat and the tormat plug that goes on the edge connector.
At one stage all of the selections with a Six stopped working but now it is back to alternate, also another strange fault is sometimes (rarely) when I hold say for example F down and 6 down it will make all the selections that it won't normally make (B6 D6 F6 H6 K6)!!!!!!

I'm sure this is very confusing to most people but I can explain further if needed.

All the best Laurence

Laurence, the most common cause for erratic selections/missing segments on those machines is resistance in the edge connectors at the stepper board. The procedure here is to obtain a simplified write-in diagram and test for continuity from the write in source (on the tormat board) through the letter and number keys to the tormat loops and on to-ground.

it is very simple. Once you establish the two places to connect your meter, you just go through each letter and number pressing both at the same time and checking for low resistance. Power off of course.

The fact that you claim it is occurring in one region does bring into question the contacts on the tormat block. Pull down the block slightly and note if there is some degree of overtravel of the plungers. Check that all the wires are connected, breaks are common here.

There should be NO sparking of the center contacts that ride the plate.

These machines sometimes develop uneven wear or wobble on the star wheel that punches the detent switch at each record slot. If that occurs along with the normal slight tolerance differences in the spacing of the tormat rivets -and- the detent switch has worn contacts it will often produce a readout pulse that is either too short, or misses entirely. You can try backing out the adjustment screw on the detent switch approx 1/4th turn to make the contacts close earlier. I have old Seeburgs in commercial service and this has to be adjusted every 4-5 years if they get heavy service.

Again, the most likely cause is the edge contacts on the stepper board.

I trust that the tormat and amp boards have been rebuilt.

Rob/NYC

Laurence,
I would approach this as follows,
First determine in which section your problem lies--the read-out (RO), is easiest to check using a "battery"--Use a known good "D" cell --pull out the Tormat plug, ground the battery + end, on a spot of bare metal, and tap the tip of the RCA plug onto the bottom of the battery. Insert the RCA plug back in, and start the mechanism scanning--if the RO is good, it will detent at EVERY slot. Try this at least two times--
If OK, I would suspect the "C" switch on the ES, check this carefully, as the "carry-over circuit" is normally where something like shows up.
On the K/L models there is another factor--some of the printed circuit boards were not soldered well, and he "thru-holes" open intermittently-- solder a wire in any "thru-hole" that is involved--PCB edge connectors also loose tension, and must be replaced. I assume you have cleaned all contacts on the edge connectors --I use an erasure, followed by "DeoxiT on an "Que- tip", for this job--
HTH , Ron Rich

Hi All,
Many thanks to Ron and Rob for your quick response and great info.
Its FIXED!!
After a days searching and eventually going around in circles I had got nowhere - lots of "ah this must be the problem" but no joy, but after a good nights sleep and some more research things were looking up.
I tried the battery test but with the negative to ground this time not the possitive (it worked)- this tripped every selection so I knew the problem was not in the tormat.

Then i swapped the two wires on the number 6 button switch to the number 7 switch ( removing the number 7 wires) still no joy so this ruled out the number 6 switch.

I then I ran a wire from both tags ( not ground loop) of the number 6 button switch down to the edge connector and soldered the wires straight to the relevant edge terminals- still no joy so this ruled out the button bank and loom and edge connector.

I thought the problem could be in this curcuit board ( the stepper board top right of back door) so I removed this for closer inspection, I had marked the tabs where the two wires meet the board and traced them along the tracks, to my suprise they didn't run through any contacts or components but straight out to the tormat edge connector.
It turned out one of the tracks had no curcuit because the "thru hole" must have had a break in it ( well done Ron) - talk about finding a needle in a haysatck!
Anyway that sorted that out but in the prosses of fault finding a tormat ferrite loop got broken and I can see no way of easily replacing this so have sourced another Tormat ( from the wonderful Leon of Jukeboxparts UK ) Its not the same one but is 100 select and I'm told the only difference is the wiring and plug so hope to have afew hours soldering tomorrow and my first happy Seeburg.

All the best Laurence

Laurence, it is relatively easy to repair a Tormat.

If a wire is open due to stress you can often just scrape off the doping and tack solder the two ends.

Idiots often used that as a handle and broke wires, three machines I bought and two that belonging to friends had required "surgery' but all are in service now.

Just be careful opening the unit, it's easy to add stress.

Rob

Hi Laurence,
Glad you found --sorry about the reversed battery--it's opposite when done on "tube", vs, "solid state" machines---I just had brain freeze--Why, oh why, did you open the TMU --sometimes you can see the two ends of the broken wire--it's almost always around the end of the unit, when someone forces them open--"fish" around--damage is already done ! Ron Rich

As I said the machine is working but has a broken ferrite ring, this causes the same selction to play every scan so not great!
I rewired the new tormat from a later jukebox using the old edge connector and rca plug from the original ( changing the wires at the tormat block) - this is a bit tedious and took a while.
Bad news is it doesn't work, I was told all 100 select tormats are the same apart from the plugs/wiring but I'm not convinced, the mech tripped as soon as a selection was made then scanned to near the end and went on to play selections one after the other. I then swapped the loom back over- enough soldering for a lifetime! I thought I may have made a mistake and got a wire around the wrong way on the new tormat but put the wires back the same on the original and it works fine ( apart form the one selection)
I think I've located a correct tormat and am collecting tomorrow, there won't be any profit in this Jukebox but lots knowledge.

You may have been given a Tormat from a solid state machine.

If so, the polarity of the W-I and R-O is different (as Ron pointed out) but the sensing loop goes twice around in order to increase gain. This was necessary because the S-S units had a much simpler pulse amp and couldn't amplify the pulse as much as the original 12AX7 based circuit.

The apparent polarity of the pulse loop wiring is different, but I don't see why that would matter in a floating circuit such as this.

That -may- have been the problem. Normally there is a small amount of noise produced at each rivet when a pulse is applied but this is below the 'knee' of the input tube and filtered by the L-C-R input to it. I've had cases where a 12AX7 with hot spots on it's cathode caused one selection to play along with whatever else was selected in a certain number group. For instance "E1" plays if anything in the "1s" is selected and "R0" if anything in the "0s" is chosen. In both cases replacing the 12AX7 cured this and one tube when tested did have quite a light show on it's cathode when under load the other tube's heater died so no test was possible.

It's a dead issue now but, did you let the mech scan out with the pulse amp plug removed and see if it did this again from a fresh start?

BTW: You have the patience of a saint. I converted a K to use 201+ backdoor back in 1998. I had to trace and chart all the wires. Doing it once was enough....

Hi Again, still one problem with the Seeburg.
Fitted a new tormat all good but the juekbox is not selecting properly and can't seem to find anything in the manual that relates to this problem.
When A sides are selecting Bsides are one slot out and visa versa, I have tried the tormat in it seems like every position and even put the old one back in.

I have noticed that on Bsides it will stop as soon as it makes contact with the correct rivet but on A sides it over runs nearly on to the next rivet, is there an independent adjstment for A and B sides? I'm pretty sure I didn't have this problem originally before removing the tormat but as said I have tried the tormat left to right in every position!

I see there are clutch adjustments that can be made- could this be the ? it's as if the mech doesn't stop quickly enough on the a side scan ( scanning right to left )

All the best Laurence

You may just have the Tormat misaligned.

Bring the mech over to the second record slot from the left and detent it, let the lift arm come up to make sure that the mech is fully locked into position. That will be A3-A4, the -rear- contact plunger is for A sides and it should be slightly on the -next- rivet which is A5. The other plunger closest to the front of the machine should be equally slightly on it's next rivet: A2.

Given all the rewiring you had to do it is possible that an error exists, but from your description, the problem is alignment.

Rob/NYC

Hi Laurence,
My peanut brain won't "kick-in"--only one smoke,and a half cup of coffee--but I think, what you have done, is wired the pug wrong.
You will probably need to look at schematics for both TMU's and figure out what the difference is--sometimes it depends on which end the TMU wires exit the TMU--
Good luck--keep us posted !
A "slow clutch" CAN cause the mechanism to "slide by" one or more selections, but I doubt this is the case here.
Ron Rich

Hi All,

Lots of adjusting and head scratching but the fault is still with us! I am suspecting a part on the mechanism known as the dash pot - anyone had problems with one of these ? It seems a bit slopy to say the least.
To recap the fault is the mechanism stops too early and picks out the wrong record on B sides.

Thanks in advance Laurence

Hi Laurence,
As I understood it, prior, it played the wrong side of the record ? The fault changed ?
Yes--the dash-pot could cause it--but it would tend not to be just on one side of the record. Out of the 1000's of mechanisms I have seen, I can only recall seeing one "bad" dash-pot--it was frozen stuck, and would not allow the clutch to move at all. I have seen a few of them that have lost the damping fluid--in which case, it is apparent instantly, in the noise made as the detent coil is fired.
It would now be my guess that your problem lies somewhere between the alignment of the TMU, the contact block (frog) that rides the TMU ( look at the pins--silver still on top--flat tops?) and the detent switch itself--contacts adjusted correctly--not "burned", "pitted" or dirty ?
If none of the above--the only thing left is the clutch itself--gummy, dirty, improperly oiled, clutch fork binding on shaft, loose pin on the clutch fork.
Have fun ! Ron Rich

Laurence, Ron Is it possible that the contact plunger block has been changed to an older one designed for V-VL?

This could lead to the situation described.

So, again if the mech is tripped at A3-A4 are the plungers -both slightly onto the next rivet? Or, are they both on the same set of front/rear rivets. The latter would indicate an older in-line plunger block.

It's a long shot, but anyone who has been around this stuff for awhile has seen what the Jepettos and shade tree mechanics can get up to.

I personally saw an LPC that had the speed unit permanently in-circuit. The mech scanned like a bat out of hell, but remarkably it did work.

A gummy dash pot would slow the trip and cause the mech to stop later. A dry one has no effect other than noise.

Rob

Hi Ron and Rob,
Thanks for your time on this again.
Sorry if I'm confusing the matter but the fault is the mech plays the next record in the slot not the wrong side of the record.
If I adjust the TMU so it plays A sides correctly when I select A 3 the plunger is slightly on to the next rivet - this I pressume is correct.
Then if I select A 4 the plunger stops on the A 4 rivet as soon as it makes contact therefore playing the record in the slot to the right (A6)
The contact block plungers for A and B are offset - looking from the reart of machine the Bside plunger is maybe 1/4 inch to the right of the Aside plunger.
I have cleaned and slightly filed the tops of the plungers as they were not flat, I will spend some more time on these.
I have adjusted the detent contacts as the manual says and cleaned contacts but will check again.
I'm sure I have had the TMU in every position possible!

All the best Laurence