July 30, 2025

STD Madness Part II

A quick recap: I got the mech working to my liking on the STD3 and re-installed in the juke. I had gone through the power supply board in the DCC recapping it and testing for correct voltages at the DCC test points. For grins I took the selector keypad apart, cleaned it, and tested it on the STD4. It was now time to make some selections and see what happened. From habit the first selection is always 266, this lets me know quickly that write-in and read-out are working. The mech stopped at 244. Now the madness began in earnest. It took me three weeks of working 1-3 hours a day to finally find the problem. A combination of bad luck and wrong assumptions lead me on the long path.

That first selection of 266 resulting in selecting 244 was all I needed. No need to pick several more selections. I had a problem. First thing is to pull the black and gray boxes and test them on the STD4 test box. Tried 266 first and nothing. Selected some 100’s and they played. So, no 200’s. It’s tough when the test jukebox starts misbehaving. Put the originals back in-no 200’s. Pulled the contact block, both wires in place for A or B side selection. Cleaned the contact block points out of habit. Double-checked the vertical and horizontal adjustment. NO 200’s. Will it pick up anything? Yes, still picking up 100’s. Dove deeper into the contact block and the right side actuator screw was not hitting the contact block enough to switch it fully up to make contact with the tormat. As a matter of fact it was screwed all the way in with no adjustment left as the screw head takes up a fair amount of space. Instead of installing a longer screw I just reversed the one I had with the screw head hitting the contact block and now had adjustment and selecting the 200’s. I put a nut on the backside to hold it tight. In fact all selections were now being properly picked up. The STD3 black and gray boxes are good.

Pulled the STD3 DCC boards one at a time and tested them. I started getting one-off selections as in 123 played 124, 147 played 148. Back to original boards and same thing. Turned out the STD4 tormat needed just a hair of adjustment-messing with the actuator screw I had gotten the tormat out of position slightly. So, I triple-checked all the tormat adjustments and got it properly aligned so that the mech picked up “the corners”, selections 100/200 and 179/279. Back to business at hand. Put all the STD3 stuff into the 4-black and gray box and all three boards. Wanted to see it all work together. Now, this all occurred over a period of several days. Of a sudden no Selection Playing indicator lights. Oh no, I must have blown a fuse-probably one of the components from the 3. I had to stick them back into the 3 to see that I had Selection Playing indicator lights there so something wrong with the test juke… again.

First step is to check voltages and to that end the question is what supplies the lamps for that circuit? Broke out the schematics. Seeburg didn’t make it easy like it was a M100B manual. No, the STD series comprises four different smaller manuals. I had to pull out manuals and folders and saved page scraps to find all this. Turns out it is F3104 a 15A fuse in the Digital Control Center for 25vac. Fuse good, I checked the cable-side wire on J3101 Pin2 on the DCC and had no voltage. Starting at the fuse with one lead grounded I chased the voltage to the back side of J3101 to an orange wire and had voltage. But not on the front side. Unplugged the cable and checked the pins. Pin2, the orange wire, was pushed in away from the plug. Remedied that real quick by pulling the pin, spreading the tangs out, and re-inserting. Now all the DCC boards and both boxes were giving correct selections on the test juke. I must have a wire problem on the STD3. Oh, the horror!

Indeed! Wire problems are the worst. It could be anywhere and there are so many wires. I had a few things going for me though. First, the problem definitely had to do with the four lines (and thus wires) of code used by Seeburg to write in a selection. These originate at the DEC or Digital Electrical Selector or keypad and go to the black box, to the buffer board in the DCC, and then to the gray box that actually writes in or charges the individual dots on the tormat.

The second factor in my favor is that wire problems are almost always at one end of the wire or the other-the contacts and connections. Middle of the wire problems so to speak are usually due to physical damage like getting pinched, shorted, or accidentally cut.

OK! I started a long tedious process of using my ohmmeter and testing these four wires from one component to the next for continuity meaning there is an unbroken wire from one end to the other. I did have a handy guide from one of Seeburg’s check out procedures handouts. But, I spent considerable time getting plug and pin numbers from schematics to plug into that illustration to be able to check wires with the confidence needed. In troubleshooting, jukeboxes or anything else, one must be confident at each step of the way that one eliminated a problem source before moving to the next possible cause. It took hours but long story short all the wiring checked out. I did not check the DCC internal chassis wiring. It’s always good, right? Now I was getting desperate. I have seen crimped on molex connectors over time and usage get loose enough to actually create an open at the terminal or pin. So I “shotgunned” pin replacement on two of the DCC’s plug and jack connectors, J3101 and J3104, that each held the four wires the code ran on. “Shotgunning” means to just replace something without really testing in the hopes that much like a real shotgun pellet blast I’ll hit something. Sometimes it’s a time saving measure, sometimes it doesn’t work at all. But I did have peace of mind that a loose connector was not the problem. Peace of mind with wiring problems comes at a cost.

Now I’m thinking that my wire problem must be somewhere in the cabling. This is a true horror. It could be anywhere. I was able to take the whole keypad panel cabling and all off of the STD4 and try it on the STD3. That didn’t change a thing. Once again I was using the quick 266 selection to see if the problem still existed. For the heck of it and because at this point I was still clueless I started making all kinds of selections to see what happened. If I picked 200 then 211 played. Pick 211 and 200 would play! Pick 100 and 111 would play. Pick 111 and 100 would play. 110 gave 101. Oddly enough 122 actually picked the correct one. 130, 140, 150, 160, 170 all played one up as in 131,141, 151, etc. It was not tormat position, believe me. I actually put records in both spaces such as 140 and 141 so I could physically see that the rack wasn’t off somehow.

I turned back to this sixteen page checkout procedure handout from Seeburg. It has a LOT of neat tests that allow one to hopefully pinpoint a problem. The neatest was the fact that using a test lead inserted into the proper pin at the external DCC plug and scratching the other end against ground I could make selections. Of course it says that if these selections play change that, if those play, or don’t play, change this. It all boiled down to the same stuff I originally tested. Black and gray boxes, and all three boards in the DCC with an occasional “replace the tormat”. Oddly enough, Seeburg made a tester for the route technician that duplicates these tests much more quickly. I’ve had a couple of them.

Stuck in the belief that I had a wiring problem somewhere in the cabling I examined that cabling between components. Could I remove a cable from here to there from the STD4 and try it on the 3? NO. All the cables intertwine so much that I would have to take it all out as one piece and that IS A JOB. I spent a couple days letting this stew, trying to figure out the next step.

It occurred to me that I had another STD3 sitting in the garage, the one I brought from Texas. I was told it was working except for the amp when I bought it. Indeed, I had actually done electronic repair on it for the guy. If I couldn’t swap cabling I could swap out the whole box. So I verified that this STD3 was working correctly and it was! The next day I swapped out the whole mechanism, the black and gray boxes, and the complete DCC unit from the STD3 to the Texas box. Got it all connected. Selected 266 and it played 244!!!! I quickly pulled the tormat from the mechanism and swapped in the tormat from my STD4. This time I practically quadruple-checked the adjustments and such. Same thing, select 266 get 244. OK, not the tormat. Damned sure not any of the boxes or boards so it must be in the DCC chassis. I had never swapped out the complete DCC until now.

I got all excited. I got this isolated at last! I started pulling out all the manuals and papers anew just in a tizzy. Yes, googly-eyed and running in circles. Then common sense prevailed. I got another DCC from the shelf. Turned them both over next to each other and started looking at wire colors to see if they matched. It didn’t take long to see that a couple wires on the buffer board edge connector didn’t match and then to notice a small repair a previous super tech had performed. I’m guessing that the intention was to replace a couple of broken or flattened pins in the connector. These aren’t regular molex connector pins. I had quite an argument with an “expert” over this one time. Seeburg used what are now called aviation pins, um….used in the aviation industry, and sell for about 3.00 each. Check ebay. No, frugal me has taken many many pins out of scrap edge connectors leaving 2-3 inches of wire to splice to. This is what this fellow did except he got pins 3 and 8 ass backwards. And you can see the tiny heatshrinked splices. So small I overlooked them. These are Data D and Data C lines respectively. It took me a couple minutes to swap them to their correct position and now the jukebox selects correctly, problem solved. If anyone ever wonders how I learned what I have over the years it is because of issues like this be it mechanical or electrical where I’ve had to spend hours tracking something down diving deeper than anyone would seemingly have to in order to find a problem.

July 12, 2025

STD Madness

Seeburg STD that is…..The series started with the STD160 or Vogue II in 1974. Followed by the 1975 STD2 Entertainer, the 1976 STD3 or Sunstar, and the last one in 1977 the Mardi Gras or STD4. These are absolutely the same jukebox inside with cosmetic differences on the outside. All parts and mechanisms are totally interchangeable. The STD 3 and 4’s are my favorite “modern” jukeboxes. I find them quick and easy to repair and restore. I brought my old standby, a STD4 I use as a test box, with me from Texas, an STD3 bought from a fellow in Texas, and now have this STD3 I recently picked up in Tacoma.

It’s about time to tackle the STD3 Sunstar now that I got it home. I like to start with the mechanism and thought I’d run down what I found on this and the process I used to bring it back to full working order. I pulled the mech base pins, unplugged a few cables and slid the whole mechanism out and put it on the bench. Someone had obviously spent time cleaning the mechanism. I don’t think a full tear-down and wash was done like I do but it had definitely had a lot of time spent cleaning what could be reached. And they did a good job. I like to get these down to just the mechanism and base. I start by removing the long piece on top of the record rack that has the Selection Playing tracks underneath. I remove the pop meter assembly and gray box mount. I throw away the pop meter stuff and cut a piece off of the left pop meter arm so that the tormat cable doesn’t hang on it and will re-use it to mount the gray box holder to.

It doesn’t take long to get down to the mech and base. I took the mech off of the base by removing the clutch assembly, rolling the mech to the right side and removing the screws from the left half of the track. Then I roll the mech back over the left half track and remove both by prying the track up while lifting the mech off. Be sure to remove the cable guide screws by the reverse switch and the cable clamp at the rear of the base or you’ll never get it off.

With a now-washed and cleaned base I turned the mech over, inspected and oiled the guide rollers and the three mechanism wheels. Look for flat spots on the wheels. It’s common and you want a mechanism to roll not slide. After re-uniting the mechanism and base I started oiling the mech. As I said someone did some cleaning but the mech was almost bone dry. Any place where metal touches metal gets a drop or two of 20 weight sewing machine oil. I use a Zoom Spout oiler. I’ve used nothing else since 1985 for oiling these mechs. I work my around starting at the tonearm assembly going to the right-just habit, and one thing I always do is remove the four screws from the “tower” and take it off. This is the casting directly behind the motor capacitor that houses the worm drive gear connected to the motor coupler underneath. It has a ball bearing that can fall out so I drag a fingernail up the shaft as I lift it off to prevent that from happening. Once oiled and re-assembled I checked for clearance and it had none. It needs .003 to .010 clearance and is done by loosening the big nut and adjusting with a hex head wrench while bobbing the bottom of the shaft up and down. Clearance you can feel will be enough. This is a good spot to mention that the proper procedure for installing a motor coupler is to push it up and then down to its final position before tightening the set screws. Doing it this way ensures that the worm drive shaft is bottomed out.

From here it’s on to the turntable gear and shaft. This one had zero end play. Once again, .003-.010 is needed. I like to remove the small plate with the adjuster so I can push the turntable shaft back and forth more than usual while oiling it. With that adjustment out of the way the clutch gets taken apart and the cross shaft taken out. A sticky cross shaft is The Numero Uno problem causing the mech to either not drop into Scan from Play position or stay in Play position once tripped. Seeburg used some kind of lubricant that hardens over time. I’ve had to use a heat gun to get that shaft out more than once or twice. If you hammer it you risk breaking the relatively fragile cast metal. Save yourself trouble and just take it apart and clean the holes and shaft real well. Once re-assembled the cross shaft should rotate easily. I use wheel bearing grease on the clutch worm gear, the top clutch gear and its mate on the turntable shaft before re-assembling. This is immediately followed by Clutch 1 through 4 adjustments.

Now I have a running mech and will connect 115vac to it and run it back and forth on the bench while manually tripping and rejecting to watch it operate. Once I’m satisfied that the mech is running right I’ll file and clean all mechanism switches. The detent points were burned and pitted on this one. The burned spot in the picture is about 40% of the contact face. It needs to be filed completely down. A fine point file took care of the pits and then a burnishing file polished the points back to like-new. I was curious as to what grit a burnishing file or tool is but can find nothing. So I used the finest grit sandpaper I had which was 400 grit and it was not fine enough at all. When properly burnished the point face will be shiny and smooth as chrome. I’d like to get some 1000 or 2000 grit sandpaper for grins to test.

I re-assembled the mech. Someone got sloppy and the Playing Indicator board was missing a couple of the washers it used for spacers. I got that taken care of, checked the tracking and points. The tormat got cleaned as did the tormat contact block contacts. I found the contact block top be horizontally off-center to the inside. It needs to be aligned so the two contacts move over the centers of the double row of tormat contacts. This is the “Read-Out Contact Block 1” adjustment in the manual. Number two is the up n down adjustment and this was needed as well. It was too high.

After all this I put the mechanism assembly back in the jukebox, got the mech base cradle properly adjusted. Someone had tightened the nuts down. They need to be just touching the metal rack so the springs can work to properly support the mech. I started making selections and this is when the real madness began.

To Be Continued