Seeburg AY160 selection problem

I am in the process of testing out a AY160 that I have just rebuilt and I am having a selection problem that I need help figuring out. I have gone through the troubleshooting section of the manual and still cannot pinpoint the problem. When I make any selection, the mech scans twice without selecting a record. I have done the battery test and it selects all the records as it is suppose too. All the tubes are good and all connections seem good. Any help would be appreciated.

Thanks,
Mark

Mark, you seem to have isolated it to a write-in problem.

Go here:

http://s1192.photobucket.com/user/Rob-N ... sort=3&o=2

D_L it from the "media options" at the right. This is the write-in circuit for a TSR-3. The only difference with yours is that the 193 ohm thermistor is inside the Tormat in the later units such as yours.

Check voltages and continuity.

Open the credit unit and clean the write-in contacts. BTW: What credit unit do you have? The write-in contacts become carbonized as time goes by due to the high voltage attracting dirt.

With power off; open the E-D link. Connect an ohmmeter to D and chassis. While looking at the meter go down the line pressing a letter and number simultaneously and, remembering the presence of the 193 ohm thermistor in the tormat, look for a reading at each letter/number as close to 193-200 ohms as possible.

If you find much higher readings wiggle the large Jones plugs that come from both Tormat and keyboard an note if resistance drops to desired readings. This is a typical problem that requires cleaning of the plugs.

First, make sure the voltages are correct and that Write-in contacts in the credit unit are clean.

Rob/NYC

Thank you Rob. I will try your suggestions tomorrow. The pricing unit is a USPU1. I have thoroughly cleaned it, but I will check those write in contacts tomorrow and get back.

Thanks,
Mark

Wont have much time to dive into this until Monday, but here is what I have done/found so far. Checked and cleaned the write in contacts, I had already cleaned this unit, but I did it again and they seem fine. Disconnected the ED link and hooked up the ohm meter. I get a very high reading from D to Chassis. 19.23K ohms ? When I press the letter/number keys I usually get around 185 ohms. Sometimes a little higher 300 - 400, sometimes a little erratic depending on the keys ? Jones plugs have been previously cleaned and the readings do not change when I wiggle them ?

Thanks,
Mark

Going to look more into this today, but I still haven't been able to isolate the problem ?

Mark,
What I would do, if you have not already done--is check every resistor in the write-in circuit. Change the WI cap, (and all lytics), change the "clamp diode" (1N0004, or better). You say you have cleaned the WI contact in the PU--which PU is installed--how did you "clean it" ? Did you properly " re-adjust" it ?
Check the TES latter circuits with an Analog meter. If poor contacts are noted, remove TES, clean with hot ammonia water--rinse well, and dry well prior to using. Ron Rich

Hi Ron,

I am about to pull the TSU5 selection unit again and check it. I have already replaced all the caps, but I am going to check everything in the write in circuit again. I have not changed the diode. I f I have one, I will switch that too. The PU is a USPU1I have cleaned the contacts thoroughly and checked operation and continuity, but I will do that again too. I have not re adjusted them. I have pulled the selector unit TES167 and cleaned it thoroughly as you described. It seems to be functioning fine. I will post again later and tell if I find something. Thank you for you post !

Mark

Mark,
What is the exact model number of that phonograph ? Which model TJU is installed, which model TES is installed ?
Ron Rich

Hi Ron,

Well, this is certainly frustrating. Still no success. I have re checked all the resistors. Caps are all new, changed the diode, and it still scans twice. can't figure out what I am missing here. The phono is a AY160UH. The components are:

Amp - SHFA$
Selector - TES167
Memory unit - 160TM1
Selector Unit - TSU5
Pricing Unit - USPU1

Your problem might be the TSU-5--It is not interchangeable with the TSU-7/USPU, unless updated.
Also--Which TJU/RCSU is installed ??

Only has a TJU3. No stepper

Mark,
CAN only have one or the other--TJU-3 should work fine
Once again HOW did you "clean" the WI contacts ???

I cleaned the W I contacts with contact cleaned and a title strip. Very soft artist brush as well.

Could very well be your problem--///////////they MUST remain dry--the INSULATED side is the only side in need of cleaning--if it has had any chemical on it, it will need to be sprayed with a plastic safe-safety solvent--and totally dry before using. The other side is gold flashed--if the gold has been removed under the contact wipers, the mounting holes must be elongated and the contact "fingers" re-positioned ( clean this side only with that solvent). See the Service Manual for contact position and pressure.
Hint-
Look at the post that the whole subtract arm pivots on. It should be held in place with an "e ring". There should be a very flat, thin washer under the e-ring--often lost ! (?) If not there, remove and use the one from the "add credit arm"--that one is un-necessary---also--oil the pivot points of both the sub arm and credit arm-20 wt.ND oil.
Ron Rich

OK. I will check it out and let you know what happens.

Thank you !