Seeburg DS 160 lost audio suddenly, all tubes are good...

I purchased my first jukebox recently and it was running ok when I got it. Had to do some minor adjustments to the selector bar and replace a light balast. Most every issue has been superficial til now. Been through the troubleshooting manual for my Seeburg DS 160 trying to figure out why it was working fine one day and then just lost sound. I have a tube tester so I pulled each tube and made sure they all were fine, which they were. I recently oiled & lubed it so I made sure all the contacts were clean. When a record is selected, everything seems to be working smoothly until it starts playing. I can barely hear any audio at all. I'm sure its something silly, but of course I'm climbing the walls trying to figure out what! Please help!

Has the amplifier been rebuilt?

How did you "make sure all contacts were clean" ?
Ron Rich

Start with the basics:

1) Is the fuse on the amp blown? If so, has the amp been rebuilt? If not --stop-- attempting to use it until the capacitors have been replaced. These amps can destroy their power transformer if the filter capacitors are shorted or too many other caps are leaky.

2) If the fuse is not blown, check if all tubes are lit when the machine is in play mode. A common problem is losing contact on the plug that connects the amp and selection unit. If that happens, you can --slightly-- bend the prongs outward to make better connection when the two units are mated.

Again, it is imperative that an amp this old be rebuilt for safe operation.

Rob/NYC

Rob,
How they got away with it, I'll never know --but the last two tube type amps Seeburg built (SHFA-4/5), had no fuse !
Original equipment for the model DS Phono, is a SHFA-5.
Ron Rich

Ron, I just pulled a schematic and you are right. Truly bizarre. Definitely something to add.

Rob

Rob,
You doubted me ?? Check out the rest of the "fusing" in that model--and it WAS, "UL approved".
Ron Rich

Oh heavens no. but I did rebuild two of those in spring 1986 and I hope I added a fuse:-)

I guess the U-L approval was based on the transformer burning out and not causing a fire.

On the other extreme, while I was in school I worked at an A-V vendor that had dealings with a co. called Dolphin Productions. They where one of only about three shops in No America that produced Scanimation. Essentially, any TV net ID or program intro for news and movies from the late '60- early 80's was produced by one of these facilities.

It was located on east 80th st a block away from where I live so easy to drop by even w/out having business there.

The process was true Rube Goldberg using two large helical scan VTRs and a goofy set up of monitors, sync and chroma generators and a several oscillators and monochrome cameras..

The problem they ran into was getting the thing certified as UL for insurance and to be able use it in a place of business because there hadn't been a "destructive test" done.

This was an assemblage of equipment that cost upwards of a half-million dollars in the late 60's and no one was going to deliberately burn it up to see what would happen.

Eventually the lawyers pressured the inspectors to accept the agglomerated approvals of each component as adequate for coverage.

I found this on YouTube: http://www.youtube.com/watch?v=SGF0Okaee1o

Also, people restore quad VTRs too: http://www.youtube.com/watch?v=IFWY2JzrrM4 This was the sort of machine in studios when I was a kid.

Not as crazy as it seems since there are literally hundreds of thousands of hours on quad videotape and most stations no longer keep much in the way of legacy equipment to retrieve the material, so one might have a small, profitable business digitizing and archiving old Captain Kangaroo ep's

Rob