seeburg AY 160 phantom selections

Hello all, I have a Seeburg AY 160 with a strange problem. When I start the mech. by pushing up the soleniod on the play control, the trip solenoid trips and the mech plays that record and 2 or 3 more next to it. this happens anywere the mech is sitting prior to start up.. I have done the following to the Juke so far: All contacts in juke cleaned, re caped selection receiver,cleaned bottom of tormat unit, added extra ground wire from tormat output cable at rca plug to ground, added extra ground wire from mech to selection receiver, checked all tubes--test ok,mech. cleaned and lubed. Hope someone has an idea why this is happening. thank you in advance for any help you can give. Norman

Questions--
Does it do this when cold, or warm, or both ?
Does it "stop" (motor shut down) at random positions along the record rack ?
Did you check solder job and "tightness" of the outer ring on the RCA plug ?
Ron Rich

solder job checked all ok, motor does NOT stop until after the double scan of the rack. problem was both warm and cold. one thing I forgot to mention in first post is that all resistors were checked, and replaced 5 off value ones. now problem seems to have gone away, however mech will still not pick up any selection. there is a diode near the regulator socket. could this be the cause of no write in? thanks for your help. Norman

Anything's "possible"--change it-1N4004 will work
How do you know you have "write-in" problems ??
Didja check that RCA plug, the TPA? The five amp fuse on the mech front, Tightness of the ground connection at that fuse-- the operation of the read-out plungers--alignment of--flatness and silver left on them --detent switch/choke ??
Ron Rich

Another hint the regulator tubes (older ones) do not flash as mech scans.fuse on mech is good

Sorry forgot to mention I tried test "C" with the battery and mech stopped at 6 reccords and i stopped test and unpluged tormat rca plug. Thanks again for your help. Norman

Norman,
You still have not answered my questions--I need answers in order to process where you are, if I am going to be of help --BTW-6 selections is not enough of a test--use a good"D" cell and check ALL selections.
Also, need whole model "number", of phonograph, and need to know if still properly equipped, as shown ?
What are you calling "older regulator tubes" ?
Ron Rich

Ok Ron I did the "D" cell test it picks up all 160 selections but does not cancel them. kept playing selections 2 nd time around. As to the "older regulator tubes I read on some other post--by Rob-NYC in the Q100 discussion on March 07 2013 that some of the newer regulator tubes do not glow. Here are all the model# on the machine:
on back of cabinet+AY 160 s2 R
on tormat selector unit=TSU3 code "A"
on pulse Amp.=TPA1 code "A"
on amplifier=SHFA 3 type "A"
on Tormat memory unit=160 tm1 type "A"
The 33 1/3 autospeed chassis is missing
will go to my eletronics store Monday to pick up the diode

Norman,
Did you check that RCA plug as I said earlier--did you check the condition of the plungers that ride in the contact block under the TMU--Did you check the condition of the silver plating on the TMU grounding bar?
I see someone has replaced the RCSU--which TJU is installed or did you just miss the RCSU? Did you replace the cap inside of the TPA--and check all resistors ?
Which pricing unit is installed ?
Ron Rich

Hello,Rich. Yes i checked the rca plug and added a ground wire from outer part of plug to the screw that secures the pulse amplifier to the main chassis. pricing unit is spu1 code C stepper unit is rcsu2 code "A"TMU grounding bar is very clean plungers are free and good condition with silver on tips ok. Onpulse amplifier, all resistors checked replaced 3, 2 caps replaced one of which is the .05 mfd one. Thank you Norman

Norman, these circuits are extremely simple but you need the basic schematics to speed things up.

If you want the simplified schematics of the write-in, read out and trip, PM me and I'll send you the links to D/L them.

This site is nervous about material, even 50 year old schematics that were never copyrighted.

Rob/NYC

Norman,
I would suggest the following be done--
Check that BOTH a single colored (usually green--but not always) wire is soldered, well, to the ring of the RCA plug, along with the shield. If so, separate the single wire from the plug and check that you get 4, or so, ohms between it and the tip of the RCA plug ( removed from the socket). Also check that the shield reads all the way to the TMU.
Check all internal voltages in the TSU--
I would also change both the 12AX7, and 2050 tube, in the read-out section. I would also remove any, all "added" grounds, as you may be causing "loop".
Ron Rich

Thank you Ron will check this out this evening Norman

Norman, Ron, adding a few inches of wire to insure a good ground is not going to cause a "loop" at that low impedance and short length.

I add this along with another such connection to the ground pins on the large Jones plugs on all my location machines. It has eliminated the "trips when a selection is made" problem.

Norman, remove the RCA plug from the pulse amp. Let the mech scan twice and stop (make sure the service sw is in the normal play position) Then plug the RCA back in and without making a selection pull up the scan solenoid (be careful -line AC here) -The mech should scan twice and come to a stop w/o tripping.

if it trips at all it is either not reliably reading out each toroid, or spikes are getting into the pulse amp.


You mentioned to Ron: "I did the "D" cell test it picks up all 160 selections but does not cancel them. kept playing selections 2 nd time around.'

In practical terms that is not possible since flipping the Toroid is what produces the pulse that trips the mech.

Something else is causing spikes to enter the pulse amp. On the two occasions that I had this problem is was faulty grounding plungers on the center plate under the Tormat. you may see sparks on those plunger as the mech scans.

In those cases I eliminated the connection to those plungers and added a separate ground lead to the cable going back to the main chassis. If this is done be sure to add a fast-acting 2-3 amp fuse inline.

If you want to try a quick test here just run a small wire from one of the screws on the grounding plate to one of the screws that secure the Tormat. --This is only for test -you must add a fuse and disconnect the original wires to the center plungers if you leave it this way.

There should be NO sparking at the Tormat rivets. If the detent switch is set to close too soon it will cause the readout pulse to be present at the plunger before it hits the rivet. this can cause erratic tripping.

Is the Tormat properly aligned? When tripped and detented the plungers must be approx 1/3rd onto the following rivets. For example, tripped @ A1 the plunger should be slightly on C1 when detented.

Finally, I have had three instances where the 12AX7 developed hot spots on it's cathode and that caused it to trip the mech at noise levels lower than normal. The joys of tubes in this section I've long eliminated....

Finally, are some small ceramic disk capacitors in the grid circuit (Pin 5) of the 2050 trip tube. these remove any vestiges of noise that get through the pulse amp. they generally don't go bad, but try adding a small cap of around 0002 to 0004 mfd across it and see if that stops the problem. On one of my earlier 2050 eliminations I had to desensitize the circuit by adding a .02mfd across that cap.

Once you have the mech only stopping when desired, we can see about the Write-in.

Rob

Rob,
On all Tormat models except the V, and maybe VL-VX models, in play position, near or at the record rack center, the plunger pin ( or "feeler contact" on late models), should be "dead center" between two rivets on the TMU, providing clutch 3 is correctly adjusted. On the V's ( and and VL-VX models, according to the Service Manual I have), it must detent with the plunger "dead center" ON the rivet. Ron Rich