seeburg 480 scans twice??

Hi Guys,
I'm a real newbie at jukebox's.
I've got a seeburg 480 lpc thats scanning twice. I've got an read the manuals but am a little baffled!
When it's scaning i've no glow or flicker from the 0a2 tubes? could this be a weak/shorted 6x4 tube?
it was working.but since I've recapped the auto speed unit(it selected records and once clamped stopped!)
it no longer picks selected records up just scans twice and stops at U1?
Hope you can help.
Rich

Hi Rich,
Welcome--Since you are a Newbie, I'll cut you a "little slack"---however the answer to your question could well be in the phonograph model number. "LPC-480", only tells me the basic cabinet design, you are talking about--need the full model designation from the ID tag, on the outside rear of the cabinet, to give you a good answer--Ron Rich

Hi Ron,
Many thanks for your reply.
The console number is ELPC480 07 290 H5
When it scans I can manualy trip it and it will play the record.
But I do think I need go away and to research my juke box further and read the schematics.It was an ebay purchase and was couriered here laid on it's back on a pallet!
I have noticed that tormat control Centre has been partly recapped,It also has issues with the record reject button(dosn't work)
Also the left channel amp output is low and over all sound is distorted. So guessing I need to recap both units and go from there.
best wishes
Rich

Hi Rich,
As it appears you have surmised--"on it's back" is not a good idea--OK- IF-properly "bolted for shipment".
Quick check--the small 32 ga. wires that ride the contact block (aka "frog"), under the TMU, are often broken--
This will cause that problem--and since it was so transported, that's the 1st thing I would suspect--
Ron Rich

Hi Rich,

I fully agree with Ron, re transportation and re the fine wires that connect to the pins under the tormat.

When we used to work on these (far too many years ago) we always looked at the above first, followed by the battery test and worked from there. It is not always a case of just changing capacitors and hoping all will be ok.

I suggest that you contact Ron and purchase his trouble shooting books.

Regards
Alan

Alan Hood
ami-man
UK

Hi Alan, and all,
Thanks for the "plug", but I really want to keep the record straight-- I have written two Guides, one of which, "The Seeburg Mechanism Guide", is intended to explain how the Mechanism section, ONLY, operates, and while there are trouble shooting "tips", and a few "procedures", it was NOT intended to be a step, by step trouble shooting process, for the "whole" phonograph. Seeburg published a large trouble shooting guide for the LPC ,and most other models.
The other one, "The Seeburg MicroLog (Digital), Trouble Shooting Guide" was written as a step, by step trouble shooting guide for all of the "160 selection models" (TM "MicroLog"), made by Seeburg from the "LS-3" thru The "STD" series models. I wrote this one, as Seeburg failed to provide anything I considered adequate.
( Should anyone wish to purchase either, please PM me)
Ron Rich

Hi Rich & Alan
Many thanks for your replys and sorry for my late reply.
I have checked the wires on the contact block ( aka Frog) and all they read continutity. I have had a pro recapp the amp and the Tcc as I know little / nothing about capictors.
I've noticed when the juke is cold after scaning twice it rest's on U1 (record playing indicator). But when it's warm it rest's on S1.After reading the manual, i have also noticed the mech when resting (after scaning twice and warmed up) has about 1/4" of lateral play. Hence i guess why it rest's at U1 cold and S2 warm? I've also washed the mech and cleaned the contacs and re-lubed.
I know I also need to make sure that the record magazine, tormat, frog and detent are within tolance's. Once I've corrected these would this make the oa2 tubes/valves glow as they don't at the moment when the scanning? I have bought 2 new raython usa tubes.
Any advise would be greatfully recieved.
Rich

I know I also need to make sure that the record magazine, tormat, frog and detent are within tolance's. Once I've corrected these would this make the oa2 tubes/valves glow as they don't at the moment when the scanning?

WHOA! Are you saying that the 0A2s stop glowing when the mech scans? The tubes should always be glowing. They should dim slightly when mech goes from right-to-left and dim (actually flicker too fast to see) when going from L-R.

Here is the schematic for the readout ckt: http://s1192.photobucket.com/user/Rob-N ... ort=2&o=18 Click the box at lower right to enlarge.

The 0A2 section is at the top. A frequent failure point is the 56k-ohm resistor. However this at the load side and thus could not kill the glow in the 0A2s unless it has gone radically lower in value -check it's value.

More likely it failure of the 2.7k or 3.3k earlier in the ckt. Failure there would be extremely rare, but it would cause what you are seeing.

Rob/NYC

Rich,
Did the 0A2's "glow before ? Most. but not all glow. Remove the TCC from the phono, and plug it in--check voltages--tubes should glow ( if the glowing type) after a minute of warm-up. As for stopping on S or U-1--no big deal, as it "coasts" to a stop,after power is shut off to the motor. Ron Rich

Hi Guys,
Many thanks again for your replys and advise.
When I got the phono in January it did work ( selecting records ect) at that point I knew little about the workings of the phono but guess the 0a2 tubes were working / glowing then.After about a day or so the autospeed unit stopped followed by the amp distorting. So decided to get them all the units recapped including the TCC.
I can now manualy trip the mech and it sounds great with the amp capped and with new needles. So i have faith with the guy who recapped the units. But the oa2 tubes still do not glow / flicker at all. Regardless if the mech scanning or not.I have tried two lots of 0a2 tubes to no avail.
I've included the schmatic of all the caps (highlighted in yellow) that was replaced in tcc (purchased a kit from jukebox friday nights).

I see that the R529 56k-ohm resistor, R519 2.7k and the R511 3.3k have not been replaced and was not included in the kit of caps / resistors. So I will get them replaced and work from there, whilst he is replacing them i will get the voltages checked at the oa2 sockets. Could the fault i have be caused by a weak 6x4 tube?
Also the record reject button on the rear of the cabinet fails to work, i have checked that there is continuity when it is pushed.
Any advise would be most usefull.
Rich

Rich,
On the rear reject switch--need the model number of that phonograph, from the ID tag on the outside rear, to answer you question ! Ron Rich

Hi Ron,
many thanks for your reply,
The console number is ELPC480 07 290 H5
Rich

Rich,
On that model, it should not make any difference if the switch is connected to the TCC, or the amp, UNLESS, "someone" has changed the wiring on the small three position mechanism plug. If there are three "pins" in the plug, it should work. If the center one is missing, you will need to connect the two red wires to the amp --black and white labeled screws, near the volume control.
Ron Rich

All else aside, you have to have proper voltages in the TCC for anything to work beyond scans-and-stops.

Assuming you have original 0A2s there must be a dim purple glow inside the anode (can-like structure in tube) for either write-in or readout to work.

At the end of the 56K-ohm resistor that connects to the "top" 0A2 you should rad approx 300vdc. The is the readout source. The write-in source is derived from the junction of the two 0A2's @ 145-150 vdc.

If the 0A2 tubes do not glow, replace the 6X4 tube. If they still don't glow check resistor values and voltages that lead to the two 0A2s. When checking for voltages in this situation, it is a good idea to remove all external plugs from the TCC -except of course the AC input.

Do be careful in working on a hot chassis, there are voltages of 400+ at the input to the filters.

Rob/NYC

One "other caution" when working on a TCC--Do NOT be tempted to "reach around behind" the edge of the TCC after you have "pulled it" partly out by the ring--If you do become tempted--make sure you have at least 20 feet of open space behind you, as it WILL, knock you back, at least that far (DO NOT AXK !!--yep, slow learner--done been hit twice ) Ron Rich