Current affairs
We started Xtar some time in the summer of 1982. We had rented an office just a few blocks away from the URL plant. We would spend part of the day at URL, and the rest at Xtar. As time went on, less and less time was spent at URL. Finally, we stopped showing up there altogether. That's why it's difficult to determine exactly when Xtar started. The idea behind starting Xtar was that we would develop the world's greatest video game, license it to someone, and retire to San Diego to live off the profits. Sadly, that never happened. We had to go out and find business. Our first project was to consult to Stern to complete a video game hardware system we had been developing while employed by Stern/URL. That got us going, and was why part of the time was spent at URL, while the rest was at Xtar.
While working on the video game hardware system completion, I was approached by my ex-boss, Seeburg's former (and now Seeburg Phonograph Company's current) Chief Engineer. He asked me to put together a proposal to develop a hardware control system for their upcoming CD jukebox. I had a few meetings with him and some of the mechanical guys I used to work with at the Dayton Street Seeburg, and prepared a proposal. Evidently, we were too expensive, and the Seeburg Phonograph Company decided to take a pass on us. They went ahead and developed their own control system, which became the SCD-1A CD jukebox. This was yet another Seeburg industry first, the first CD jukebox. Things went well for the Seeburg Phonograph Company, until the competition caught up with their own CD machines and their longer-established distribution and servicing groups.
Things went along for some period of time, and I lost contact with the Seeburg guys. The Seeburg Phonograph Company again fell on hard times and was purchased by a group calling themselves ‘Seeburg International', and moved into a sheetmetal factory on Chicago's south side. Evidently, funding was provided by the old Seeburg distributor in Mexico. They set up operations in the building next door to their new benefactor, and started building jukeboxes. This is where the Blast and Neon CD machines were built. I had moved out to San Diego some time before, but had an opportunity to come back to Chicago in 1995. It may have been for a Seeburg reunion, I just don't recall. I made arrangements to get together for lunch with my ex-boss, Seeburg's venerable Chief Engineer, still holding that position after all these years and through the various incarnations of Seeburg. We met at the plant, and he gave me a quick tour before lunch. This was a far cry from the heydays of Seeburg, with their four-square-block plant on Dayton Street. But, they were building machines, not many, but a few went out the door each day. There were very few people around they day I visited. I think there was something going on with management, and kept my nose out of it, since it was really none of my business. From what I understand (anyone having more accurate information, please contact me), a self-proclaimed engineer and marketing expert took over, booting out everyone (engineers and executives) from the old organization. After returning from my trip, I got in touch with my old boss, to thank him for the tour. He then informed me that everyone had been locked out of the building, and had been told that they would be contacted to let them know when to come back. Evidently, this went on for a few weeks. Then, someone told me that the entire building was emptied, and Seeburg was no more. I contacted my old boss, and he knew nothing about it. He went down there (he lives in one of Chicago's far north suburbs) to try to get in, and confirmed that the doors were locked and everything was missing. This includes all of the priceless documentation that had been amassed ever since Seeburg had started business way back when. Those drawings are probably sitting in a landfill somewhere on Chicago's south side to this day.
Apparently, nothing more happened for a year or so, and then the seeburg.com website popped up. This seems to have been set up by someone buying the domain (If no one else has a specific domain, it's yours for about $25.00 annually). They set up shop in the low rent district of Lansing, Michigan. I recall reading a posting on a newsgroup, saying that the author of the posting had stopped by the address, and attempted to buy something. He said the place was surrounded by barbed wire, and the people in the building sent him packing. This new Seeburg.com advertised having all kinds of spare parts, manuals, and even jukeboxes available for sale. I know that they attempted to sue at least one aftermarket supplier for using the Seeburg name on some of the aftermarket products, products that the supplier had obtained permission to reproduce from the last real Seeburg. Also, I recall reading several newsgroup-posted horror stories of people sending seeburg.com money in good faith for replacement parts or jukeboxes, and never hearing another word. I attempted to contact Seeburg.com, stating that I was an ex-employee, and wondered who their executives were, etc., in the hopes that someone I knew from before had stuck around. I was treated like I was trying to gather insider information so that I could take over the company. I gave up after that, but read an article in Always Jukin' about the FBI closing Seeburg.com over mail fraud, and its proprietor getting some jail time.
This should have been the end of my Seeburg involvement, but it was not. Bob Blankenbeckler who was the president of the Seeburg Phonograph Company in better times, remembered me from the request to quote on a control system development for their CD juke. He called me one day asking if I would be interested in developing a new CD jukebox control system with him. This version was to have nothing to do with Seeburg, except that he had been in contact with a member of the Seeburg family, who had expressed an interest in getting involved. However, the machine would not carry the Seeburg name. He said that he had contacted a number of the folks from not only the Seeburg Phonograph Company, but the Dayton Street Seeburg, and was putting together a group to develop a new machine. This machine was to evidently go into the discos, since he thought it was very important to minimize dead time. The next selection played had to start immediately after the last, with no silence whatsoever. He also wanted a simple way to display the selections available on the machine. I was really interested, since it would be an opportunity to work with the old ‘gang' again. I came up with a couple of ideas to address his requirements.
For the dead time issue, why not use a pair of CD players, both accessing the same CD carousel or magazine, depending upon the mechanical design. One player would play the current selection, while the other loaded up the next and cued the appropriate track. Note that the CD has solved the problem of locating all the tracks; they are recorded on a special track at the beginning of the CD. This is what is read when you first put the CD into the player. It determines how many tracks there are, how long each is, and the total amount of music on the CD. When the current track has completed, its player replaces the CD in the magazine in any available slot, and goes on to locate the next CD, while the other player (the one that was cued up) is now playing the next track. The microprocessor controlling everything keeps track of what CD is where at all times, and can deliver any requested CD to either player or to the routeman for replacement.
For the selection display, I had another idea. Now that memory is cheap, why not just scan the album covers and selection listings, and save them on a hard drive inside the machine? A jpeg image of each could be saved on a floppy disk that the routeman took with him to load up on the machine. USB flash sticks we still in the future, this was 1996. Selections would be displayed on a video tube like the VMC, but this time it would be a touch screen. An image of the actual album cover would be displayed, with perhaps nine or sixteen different covers shown at the same time. The customer would then simply point to the one he wanted, which would then fill half the screen, with the available selections on that album taking up the other half. Simply point to the song(s) you want (which would be highlighted in response), and hit the select button.
Sadly, this new machine was not to be. Bob passed away shortly after he and I started talking about the project. Without him to drive it, the project went nowhere.
My Interest in Seeburg returns
In between our losing bid for the SCD1 control system in 1985 and about 1993, I was absorbed with what we were doing at Xtar, and Seeburg faded further and further from my thoughts. Then, one day in 1994, I got a phone call from a guy by the name of Mike Zuccaro. He had been given my name and phone number by my old boss, Seeburg's perennial Chief Engineer. Mike had been doing a series of interviews for a hobbyist magazine with former Seeburg engineers, such as George Bosen, who designed the Tormat, and Ed Meixner, responsible for the design of all the early transistorized amplifiers. He was interested in interviewing me about my experiences at Seeburg. As it turned out, Mike lives about two miles from me, so we developed a strong friendship, due to similar interests. Mike never published the interview. I guess had had just too much to say (as evidenced by all these ramblings, assuming you've hung in there reading until now).
When I told him about my experiences with the black and gray boxes, he said, “You know, there is no information whatsoever out there about how they work and how to fix them. You should really write a book, to help people keep their machines running.” I said, “Are there really that many out there?” Mike convinced me that writing a book was the right thing to do, so I got started. The first thing to do was to get in touch with my old boss. He was kind enough to send me all the schematics I asked for, including copies of the logic schematics for each of the custom chips, and the original schematic drawings for the five PC boards in the boxes, plus the original schematic for the red box. I needed the originals so that I could get high quality reproductions made. I am honored that he trusted me with these. I had them photographed and returned them to him immediately. Sadly, they too are probably in the same dump on the south side of Chicago as is all the other original Seeburg documentation. I should have hung onto them.
Books
Preparing the first edition of ‘The Seeburg Black and Gray Boxes' took about a year and a half. Much of this involved trying to get all the illustrations prepared, and interviewing as many of the guys who worked on the design as possible. My main sources were my bench experience, the schematics, the Chief Engineer, and the guy who had designed much of the circuitry, the same guy who I had worked for, followed by him working for me. I sent them both preliminary copies and got numerous corrections and suggestions back. The schematic fragments and timing diagrams for the 1st edition were done using a schematic capture program we had at work. It was not tailored at all towards generating illustrations that could be included in a document. Its output was supposed to be sent to a pen plotter. That's why some of the illustrations in the 1st edition are a little hard to read. In addition, I noticed that I had made some clock edge errors in several of the timing diagrams. I noticed this right after I got the first order back from the printer. I fixed the diagrams, and added an errata sheet to each copy of the 1st edition. By the time the 2nd edition was ready to go, I had discovered Visio, which I have used for all the other manuals I have authored since then. The 2nd edition has been available since 1998, and has gone through two separate printings.
My next effort was ‘The Seeburg SHP Amplifiers', which covers the SHP1, 2, and 3 amplifiers used in all Seeburg jukeboxes built between the 1972 and 1984 model years. This includes most of the black and gray box machines (except LS3, USC1, USC2), the last electromechanical 100-selection machine (the SB100), both red box machines, all of the SMCs, and the 100-selection MCU based machine (the 100-79M). I wrote it as a separate booklet due to the wide variety of machines it supported.
Next was the biggest book I have written, ‘Seeburg's Red Box and MCU Systems', covering the red box machines, all of the SMCs, and the 100-79M. I was then asked by Ron Rich (an ex-Seeburg field engineer, having forty years of in-the-trenches experience) to help him with his ‘The Seeburg Microlog Troubleshooting Guide' which gives more in-depth troubleshooting tips for the black and gray box machines. It includes troubleshooting tips for mech problems and amplifier problems not covered in my book. My assistance was limited to formatting for publication, spell- and syntax-checking, cover artwork, and actually getting it printed. As you've no doubt noticed, I sell it here on my website. It and all the books featured here on my website are also offered by Always Jukin', Victory Glass, Game Room Magazine, and Stamann Musikboxxen in Germany.
Recently, Ron asked me to help him with his ‘Seeburg Mechanism Guide', which covers all the 7-inch mechanisms Seeburg built. Here, I did the layout, the paragraphs describing the VMC, the ‘Seeburg Periodic Table of the Mechanisms', the VMC mech schematics, and the cover. My most recent effort is ‘Seeburg 100-Selection Jukeboxes of the 60s and early 70s', first published in June of 2005. It covers seven similar models, starting with the U100 Mustang of 1964 and ending with the SB100 Magnastar of 1975. All of these machines use a similar electromechanical pricing and selection system. The book covers the variations between models, and how all the circuitry works, including the amplifier, optional stepper, PRVC, Pricing Units (three different styles), and selectors.
An FC1 of my very own
I tried to get in touch with the person I sold my Color Organ FC1 to before moving from Chicago to San Diego, but had no luck. But I really wanted and FC1 with or without the Color Organ. In May of 2004, I bought an FC1 jukebox from an internet auction, and had it shipped from Houston, Texas to San Diego. I got a call from the freight company to come and pick it up. Mike Zuccaro and I went down to get it. The machine with all guts installed was too heavy to lift into the back of my wife's Explorer to take it home, so we wanted to take the amp, control center, and mech out to lighten the load. But the lid lock linkage was broken, so we couldn't get it open. On this machine, when you turn the key, it unlatches the right hand lid lock and activates a linkage down to the bottom of the front panel, which turns a torsion bar running below the front panel to activate yet another linkage to finally release the left hand lid lock. The ‘E' ring had fallen off one of the pins in the linkage, so the torsion bar would not rotate. I could only get the right hand lid latch released. With this done and the lid partially raised, I could sneak a small shaft but long screwdriver in between the left hand side of the cabinet lid and the front panel to release the latch. Luckily, I remembered from my Color Organ installation days the interior layout of the cabinet. We got the cabinet and subassemblies home with no further incident. I resisted the temptation to plug it in to see if it works. As it turns out, I'm glad I did, and you should resist the temptation, too.
I decided to do a partial disassembly of the cabinet, to clean out all of the spilt beer, tobacco juice, and dead bugs. This machine was probably no filthier than others, but it sure stank of cigarette smoke. I made sure I had a copy of the Parts Catalog for the FC1 before even thinking about starting. I got my copy from Always Jukin'. The first thing I did was to take the top and front lamp panels completely apart and replace all bad 2182 bulbs. As I disassembled each major piece, I referred to the exploded parts diagram in the Parts Catalog to make sure I was familiar with each part. As I removed each screw, nut, washer, E ring, etc., I put them into a baggie, with a label saying what part of the machine the hardware came from. In addition, I took a lot of pictures. I'll post some of them to this website in the future, until I run out of disk space for the site. If you decide to disassemble and clean your machine, you should do the same. I cannot stress how important it is to have the Parts Catalog for your machine handy, to bag and label all the hardware, and take plenty of pictures!
I took everything out of the cabinet and cleaned it. I took everything off the cabinet lid (which has lots of stuff on it). The only thing I did not do was to remove the cabinet lid from the rest of the machine. This is a two-person job, and my oldest son was not big enough to handle his end.
The FC1 has many small holes and cracks where pieces don't exactly line up. This happens because the cabinet and lid were made almost exclusively from either formed sheetmetal or aluminum extrusion sections, rather than molded pieces with no cracks in the corners. This makes it possible for any liquids spilled on the control panel to make their way into the guts of the machine. Most of the mechanism is protected by the title strip framework and glass, except for the sheetmetal parts holding the fluorescent bulb assembly. The upper and lower channels that support the front decorative panel and the formed and painted sheetmetal parts against which the lid closes are not protected at all, permitting these liquids to sit there, eventually pitting the plating. This is what happened on my machine, resulting in many of the inside sheetmetal parts being pretty badly pitted. I got all of them together, and took them to a plating house here in San Diego, and had them bead-blasted and zinc plated. (Bead blasting is more environmentally friendly than sand blasting.) Back when Seeburg had more tooling money available, one of the things the cabinet guys did on each new model was to design in small gutters and drains inside the machine, to deflect liquids away from the important parts, dumping them out the bottom.
The control panel (part of the cabinet lid) mounts the now-playing indicator, instruction glass (1st, 2nd digit, etc.), the selector, either a Dollar Bill Validator or a glass back-lit panel with ‘CLX' in purple script (Roman numerals for ‘160'), the coin entry, and the coin scavenge button. On my machine, this panel has a lot of wear, especially around the selector and coin entry. I removed it, had it bead blasted, and painted with a black textured paint that comes close to the original pattern. I had to remove everything from this panel before it could be painted. More baggies and photos.
There were a couple of cabinet problems that I wanted to fix. The upper lid folds down over the selector panel to transport the machine. Once the machine is on location, there is a hole in the right rear of the cabinet that you insert your finger into, releasing the catch for the upper lid. You can then raise the upper lid to its full position, where it latches into place. If you release the same catch, you can fold the upper lid back down into its shipping position. The latch is actually a pin made of a weld stud, which is welded to the lower end of each of the lid arms. It rides on a sheetmetal spring-loaded cam piece until it falls into a notch. The right-hand weld stud on my machine was broken off and lying in the bottom of the cabinet, so I removed the upper lid from the machine and took it to a welding outfit to be TIG welded. Works fine, now. The other problem was with the spring and cable assembly. It is used to provide tension on the upper lid, to keep the upper and main lids together when you're lifting the main lid, but don't have the upper lid latched in place. The cable is used to insure that the two lids don't separate too far, which would snag the spring on the internal cabinet structure. On one side, the spring had been stretched, and the cable had frayed and broken, probably due to a routeman who wasn't too familiar with the insides of this machine forcing it. This is a pretty uncommon part, but luckily the guy I bought the machine from had a spare and was willing to send it to me. If you're reading this, thanks, John.
I replaced most of the silkscreened glass pieces with a set that Ron Rich sent me. I now had almost everything out of the cabinet and most pieces off the main lid. The main lid has a couple of very large springs that pop it up when unlocked, and also make it easier to lift the lid up. I decided I did not want to mess with these. Besides, they were in very good shape. I laid the machine down on its back and checked the casters. All four were in good shape, so I left them alone. Next, I removed the lower grille to get access to the speakers. All four (two woofers, two tweeters) are located in the cabinet base, just off the floor. They are angled so that the sound projects upwards. If the machine is on a rug, the rug absorbs a lot of the sound. I removed all four speakers, to clean and test them using a battery across the speaker terminals. They all worked fine, so I removed to crossover network to check it out. On this machine, it's located on a post inside the sound baffle. To get at it, you must remove the speakers. The speaker wires are connected directly to it; there are no connectors except for the push-on terminals at the speakers. Removing the cash door and coin box also gives easier access. I checked the components; they were all good, except for a questionable solder joint on one of the capacitors, at the point where the wire goes into the capacitor body. I resoldered it, but there was a lot of stress on the wire due to the terminal strip it was connected to. More about this later.
As part of the cabinet and lid disassembly, I removed all of the cabling and cleaned it up. Seeburg used a gray-colored PVC zipper tubing to protect the larger cable assemblies. The smaller cables (two-five wires) were protected with tubing not having a zipper. The zipper tubing actually comes as a flat piece on a roll. One side has a molded-in tongue, and the other side has a molded-in groove. At the factory, a special harness was made which would hold the cable in place while you put the jacket around it, followed by pulling the ‘zipper' (a specially-made plastic piece) that joined the two sides of the jacket together, completing the tubing. I'm not sure if it's due to the stuff they made the tubing out of, or if it attracts cigarette smoke, or what, but every piece of tubing in that machine had a brown slimy sludge over it. For the zipper tubing, I contacted the original supplier who sent me one of the plastic tools to zip it back together (it simply pulls apart, but getting it back together can be difficult). I unzipped all the tubing and cleaned it and the wires with copious amounts of window cleaner and paper towels. For the cables which were not in zipper tubes, I cleaned the outside of the tubing and as much of the cabling as I could get at the same way. I did not pull the contacts out of the connector housings so that I could get the cable completely out of the tubing. I felt this was going too far.
It was time to move on to the mechanism. I cleaned and degreased it using the methods Ron Rich discusses in his ‘Seeburg Mechanism Guide'. Luckily, my mech was in pretty good shape. It did not have any clutch or cam problems which would have required more than the partial disassembly I did. So I waited for a hot day (you don't have to wait too long in San Diego for a good day, that's why I moved here!). Before hosing down the mech, I removed the motor, trip solenoid, popularity meter solenoid, tormat, and pickup. Since I could see a lot of gunk on the transfer arm casing and gear, I removed the magazine and popularity meter so that I could get at everything. I took color photos of the switch plate so that I could identify where the wires I removed went. I got some maximum strength degreaser concentrate, and cut it with about ½ the water it said to use. I put the diluted degreaser into a spray bottle, put the mech out into the sun close to a drain, and started spraying everything that was discolored. Once I had a liberal coating of degreaser on it, I waited for a few minutes, and hit it with the hose, flushing everything out. As soon as the water ran clear, I turned the hose off and took a close look at everything. I saw a few spots that needed a second dose, so I repeated the treatment, using an old toothbrush for some of those hard-to-get-at places. This time everything looked clean, so I got out my air compressor and blew everything dry. I use this compressor for the kid's bike tires, car tires, and inflatable swimming pool (when the kids were smaller) and for drying mechanisms. It wasn't very expensive, well worth the investment. Next, I got out my trusty oiler and started lubricating everything, again using Ron's guide. Note Ron points out several spots that the standard Seeburg lubrication chart misses, so I made sure I got those too, even the hard to get at ones. It's very important to lubricate the mechanism immediately after you degrease it, so don't put it off and leave the mech lying around dry. Once I was satisfied with the lube job, I put most of the parts back that I had removed, and checked the appropriate adjustments. I left the magazine, tormat and popularity meter off for the time being, so that I could make sure that the clutch and transfer arm lubrication was adequate. There's a roller buried down in there between the clutch and safety plunger that's pretty hard to get at, but I got some oil down there too. I was also careful to apply a bit of bias to the motor coupling when I reinstalled it. I also checked the turntable bearings. Luckily, they were not seized and the rubber bushings were not hard. All in all, my mechanism was in very good shape. It just needed a good cleaning and lubrication. If your machine has not had this done to its mechanism in the last five or ten years, you should definitely either do it or have it done! If you're doing it, get a copy of Ron Rich's Seeburg Mechanism Guide.
Now it was time to see if everything worked. The first thing I did was to remove all three PC boards from the control center, and plug it in to measure the AC voltages. I wanted to make sure that the power transformer was okay. It was, so I set up the mechanism and control center on my work bench. The mechanism will plug directly into the control center without the cabinet cable, so I plugged them together and manually energized the play control add solenoid. The mech took off, scanned twice, and stopped. This told me that the motor was working, and that the 24 VAC supply worked too, since the scan subtract solenoid energized each time the carriage hit the 179/279 end of the magazine. I manually energized the solenoid again, and ran it back and forth a few times, looking at everything and listening to it. Working at Seeburg, I've heard a lot of mechs, so I know when one doesn't sound right. Not that I know what's wrong immediately, but I do know when it does and doesn't sound okay. This one sounds okay, so I started to manually trip it into play, then back into scan, watching and listening to everything. By doing this, I saw a couple of spots that could use a bit more lubrication, so I took care of that. It goes through the transfer cycle just fine, there is no hesitation on the part of the clutch shifting lever coming out of the scan or play notches, like some other machines I've seen. The clutch shifting action is nice and smooth, and there is very little wear on the clutch.
While removing the boards, I noticed that there was a burned resistor on the power supply board. Not a good sign. This is the 390-Ohm (R3113) resistor used to bias the –13 V reference zener for the black and gray boxes. As it turns out, Q3120 was also bad, along with the reference zener diode, CR3110. I replaced all three. This is why I was glad I didn't plug it in and turn the machine on when I first got it home. With these problems, I could have easily destroyed both boxes. The resistor is a half-watt unit, but runs very warm, since it is very close to its half-watt rating. To be safe, I replaced it with a one-watt resistor. If you're working on any of the Microlog machines, you should replace this resistor. Once all three parts were replaced, I checked all the electrolytic capacitors, which were all good. I connected the DCC to a variac (a variable transformer, which allows you to bring its output voltage up slowly, instead of just hitting the DCC with 120 VAC). I started with an output voltage of about 50 VDC, and brought it up 10 volts at a time until I hit 120 VAC. I did not have anything connected to the DCC; specifically I did NOT connect the black and gray boxes yet. I wanted to make sure I had a good power supply first, since I did not want to take the chance of blowing out a potentially good black and gray box. The DCC checked out okay. Next, I made sure that the turn-on reset circuit worked. This is a delayed -27 VDC output of the DCC, delayed by a couple of seconds from the main output. It is used to reset the black box. It worked fine.
It was time to see if the system worked. First, I had to replace the mechanism magazine, Tormat, popularity meter, and now-playing indicator since I had removed them when I degreased the mech. After reinstallation, I checked all the pertinent mechanism adjustments, specifically those relating to the Tormat and detent timing switch. Once this was done, I set everything up on the workbench, since I had previously removed the cabinet cabling from the juke to clean it up. I'd much rather work on everything spread out on the bench, rather than have to troubleshoot a problem with either the black or gray box while they are installed in the machine. It's much easier to get at everything when it is spread out on the bench; you don't have to worry about any of the PC boards shorting out to the metal parts, for example.
I connected the black gray box, selector and instruction lamp assemblies to the cabinet cable. Next, I plugged it in and held my breath, followed by checking the supply voltages with everything connected. The two supply voltages (-13 and -27 VDC to the black and gray boxes were within tolerance. The +27 VDC supply, used for the trip circuitry, was also within tolerance, as was the Write-In/Read-Out supply, at about +125 VDC. So far, so good. I had the Pricing Programmer Board unplugged, giving free credit, so I made the simplest selection of all, 111. The mech went into scan, and it tripped at selection 111! I did not have the now-playing indicator plugged in, but I could tell it was the correct selection from the label at the top of the record magazine. Feeling lucky, I entered 222, and manually tripped the mechanism, since I had not plugged in the amplifier yet. The amplifier mute/trip relay has to be working in order to reject a record on these machines. The mech went right to 222, and tripped. Wow! Now, if 100 and 133 work, that means chances are very good that everything else will work, since these four selections use all four data paths within the selection system. I went ahead and made these selections, and again manually tripped the mech. They both worked. Next, I made the series of selections I had always made so many years ago while verifying correct operation:
111, 222, 100, 233, 144, 255, 166, 277, 178, and 279
This verifies that the selector and gray box are working correctly. The first four selections (100, 111, 222, and 233) verify that the black box is working correctly, except for the Pricing function. I spent some time probing various points on both boxes. I did this to verify once again that the waveforms published in my ‘The Seeburg Black and Gray Boxes' were correct. I'm also adding some waveforms for the next edition (the Scan Start board in the DCC), so I wanted to make sure the timing on those were correct, too. I was halfway hoping that there would be something wrong besides the power supply problems I talked about earlier, since it has been so many years since I trouble shot one of these, but I guess the Microlog gods were smiling on me this time. The next thing to do was to make sure that the Pricing part of the black box worked, so I shut the thing down, installed the Pricing Programmer Board, plugged the coin switches into the cabinet cable, and fired it up again. This machine came with the coin equipment still installed, so I inserted a quarter into the top of the rejector. It hung, so I opened up the rejector, cleaned all of the muck out of it, and gave it a shot of silicone spray for the moving parts. After this, it worked. So I ran a bunch of nickels, dimes and quarter through it. The Programmer board included was the ‘standard' 2/25 cents, 5/50 cents. I ran through the checkout procedure we used at Seeburg (and is documented in my black & gray box book. I didn't have any half dollars handy, so I just hit the coin switch instead. The Pricing function works, too.
The next thing to do was to reassemble the machine. The painted control panel was back from the painter, and all of the plated parts are back, all nice and shiny. Reassembly went without incident, since I had taken the time to try to organize myself and had taken so many photos. The Parts Catalog came in handy here, too, since it also usually shows the order that things have to be assembled. Each page gives an exploded diagram of a certain part of the cabinet. Each part has a number, which relates to a part list on the facing page. The list gives the Seeburg part number, and the part name. This comes in handy in case you need to order parts. Some of the suppliers simply ask you for the Parts Catalog page number and the item number, using that to locate your part in their inventory rather than the Seeburg part number. The parts catalog usually shows you what hardware (nuts, bolts, etc.) to use to fasten the parts together, how many, whether there should be a lockwasher, etc. However, the catalog shows how the prototype was built, which sometimes varies from what you have in front of you. Here's a couple of possible reasons: A change may have been made on the production line that didn't make it into the manual, or the folks on the line didn't exactly build it the way Production Engineering intended it to be built, and the inspector didn't catch it. That's why it's so important to take a lot of photos while you disassemble the machine. I must admit that I didn't take enough, for I had some left-over screws and nuts for one area, and I had to run out and buy some different length screws for another area. But the machine went back together pretty easily without any major parts left over. The biggest problem was the spring and cable assembly I talked about earlier. I had to figure out how to get the cable into the spring, since it sits about one quarter of the way down the coils of the spring. Another thing was to make sure that I had assembled the washers, eyelets, and E-rings in the correct order for both ends of this cable. Both sides of the machine are mirror images of each other. The Parts Catalog really came in handy here, for it showed in detail the parts order.
The machine was coming together pretty good. One problem was that the fluorescent lamp for the title strips did not work. I went to the local hardware store followed by Home Depot, even a lighting store not far from where I live. No one had it. It's a 30 Watt, 30 inch tube. I started calling around, and finally found a specialty store in town that had it in stock. I decided to get another starter, too, just to make sure it would work when I got home. I plugged in the new bulb, and it lit right up.
Next, on to the amplifier. I checked all of the electrolytic capacitors, on both PC boards and in the chassis. I was lucky again, they all checked okay. I removed all four output transistors, and all four driver transistors. I don't have a curve tracer, but my friend Mike Zuccaro has about three, so I took them over to his place to check them out. They, too, were good, so I put them back in the amplifier. My amplifier has the early version of the bias circuit, the one with the transistor under the heatsink, not the later version using the stabistor. This transistor checked okay too. I made sure that the connections to the bias circuitry had the jumpers connected directly to the PC board as a safety measure were indeed connected and were soldered to their little solder posts. If you have an SHP-series amplifier, I strongly suggest you make sure that these jumpers are connected. Otherwise, you may have the resistors on the driver board burn out on you, and they may take the drivers and output transistors with them. I made sure all of the resistors were of the correct value (not just by reading the color codes, but by lifting one lead and actually measuring the resistance with an Ohmmeter). The emitter resistors for each driver were changed from 560 Ohm ½ Watt to 100 Ohm 1 Watt flame-proof units. You can find these if you look around on-line or in your local electronics store. (Your local Radio Shack probably does not have them). Also, I made all of the continuity checks I recommend in my ‘The Seeburg SHP Amplifiers' book before applying power. Please note that items g) and h) in that checklist are incorrect. Instead of continuity to the emitter of Q16 and Q26, it should be the collectors of those same transistors.
As recommended in the book, I built the simple test jig. This consists of a line cord with plug, a socket to plug the amplifier line cord into, and a 60 Watt light bulb in series with the hot side of the AC line. This test jig will show you if you have a serious problem with you amplifier, before it causes amplifier destruction. If the bulb lights brightly when you plug the amplifier in, there's a problem you need to fix before going further. The problem could be something like a shorted transformer, filter capacitor, etc. If the bulb flashes briefly, then it should be safe to power up the amplifier. A very similar test jig was used at the factory for each new amplifier coming off the production line. I only got a brief flash when I plugged in the amp, so it was time to go on to the next step. Since I had no idea when this amplifier was last run, I decided that I should form the electrolytic capacitors in the power supply. This is good for the capacitor, especially if it has not been under power for a number of years, as it builds the insulating oxide film on the aluminum foil making up the electrodes. I started out with the variac set for 50 VRMS, and built my way up to 120 VRMS, 10 volts at a time. I waited about five minutes at each step, so this took a while. While waiting, I would constantly check the heatsink with my hand, to make sure it was not running hot. Much to my relief, it was only warm.
Once I had brought the line voltage up to 120 VRMS, it was now time to set the bias. My old QA supervisor (the person who actually determined why the SHP1 was catching fire) came up with a more accurate method. I recommend this method, although I have heard from a few folks saying that when they do this adjustment, their heatsink runs way too hot. If this is the case, revert to the Seeburg-recommended method. My guess is that some other components in these amplifiers have changed value. Using his method, my amplifier bias adjustment settled right in. At long last, it was time to reinstall the amp into the jukebox and listen to some tunes.
I installed the amp, plugged in the volume control, the jacks from the mech, and connected the speaker wires to the amplifier output terminals. I turned the machine on, and heard the characteristic thump coming out of the speakers as the amplifier outputs stabilized. I made a selection: ‘Hotel California' by the Eagles, and cranked the volume up. It sounded great, except that the highs from the right channel were kicking in and out. I played with the tone controls, and sprayed some tuner cleaner into the switches, thinking that the contacts were noisy. That helped somewhat, but didn't cure the problem. I shut the machine down, and swapped speaker wires to try to determine where the problem was. The right channel still sounded bad, so I knew that the problem was not in the pickup or amplifier, it had something to do with the speakers. But when I checked the tweeters when the machine was apart, they both made noise. Granted, I only used a battery to make sure that they put out something. So now it was time to swap the tweeters to see if the problem followed. To do this, you have to remove the front grille, which is no easy to do once everything is back together, since now you can't lay the juke on its back. I had to remove the front panel to get access to the screws holding the top of the grille in place. The grille is held in place at the bottom by eight or ten screws, and there's only about an inch or so of ground clearance. Luckily, the screws are hex-head, so a ¼ inch open end wrench works. I only loosened them enough so that I could get the grille off. Next, I swapped tweeters between channels. The wires aren't long enough to simply exchange connections. Besides, you have to remove the speaker to get at the wires. Swapping tweeters did not solve the problem: the right channel still sounded lousy. This told me the problem was in the crossover. Remember the questionable solder joint on the capacitor? These capacitors are 15 mFd non-polarized units, so I went to my local electronics store to find some. I couldn't find 15 mFd non-polar, so I settled on some 6.8 mfd non-polar, putting two in parallel to get close to 15. Since it's such a pain to get at the crossover network on this machine, I went ahead and replace the capacitor for the left channel, too. The machine has been working fine ever since.
