Phonoland

Hello. New to this forum and jukeboxes in general.

I own a recently acquired Wurlitzer 2710 with the 544 amplifier. I have removed the amplifier chassis intent on replacing old electrolytics, old diodes and molded capacitors etc. as the unit was functioning fine but it seems appropriate to do so, as advised.

I have a clean and legible copy of the schematic for the amplifier to refer to.

One question to start.....Which pins does one jumper on the 11 pin octal junction connection on the 544 amplifier to power it up? I want to bench test the chassis independent of the rest of the juke-box. I have an isolated variable transformer that I will be using to bring the amplifier chassis up to voltage after I've replaced the caps etc.

Thanks and regards. Vince

It seems to me that if the schematic is in your posession, it would clearly show the amp connector socket/plug, along with the numbered pins - so tracing out the circuit is then easy - and then a suitable jig could be fashioned to bench test the amp.
This of course requires the ability to read schematics along with understanding them.

Even more better--every WurliTzer schematic I have seen shows the "dummy plug" wiring. Ron Rich

The drawing shows the jumpers as dotted lines.

Vince, on this schematic:
http://arcarc.xmission.com/PDF_Jukebox/ ... s/544a.pdf
The pins to be jumpered are marked with dotted lines. They are:
1 & 2
3 & 8.

There is no point in replacing the power diodes unless B+ appears weak or absent. You may find the large electrolytic caps are OK after careful re-forming. ALL paper caps should be replaced.

Rob/NYC

If you replace the electrolytics, be careful with polarity.

MattTech wrote:It seems to me that if the schematic is in your posession, it would clearly show the amp connector socket/plug, along with the numbered pins - so tracing out the circuit is then easy - and then a suitable jig could be fashioned to bench test the amp.
This of course requires the ability to read schematics along with understanding them.

Thanks for this. It took a lot of effort to get a schematic of the 544 amp that was legible. Dealing with the schematic vs. the actual physical layout is confounding for those of us with some left-brain deficiencies However, I am taking my time and checking and rechecking what I see in the schematics vs. what I think I see in the chassis in the spirit of the carpentry axiom: measure twice, cut once

Ron Rich wrote:Even more better--every WurliTzer schematic I have seen shows the "dummy plug" wiring. Ron Rich

Thanks Ron....but I don't see it. Doesn't mean it isn't there, of course, just that I can't see the forest for the trees perhaps.

eddie wrote:The drawing shows the jumpers as dotted lines.

Thanks for that....will have another look.....

Rob-NYC wrote:Vince, on this schematic:
http://arcarc.xmission.com/PDF_Jukebox/ ... s/544a.pdf
The pins to be jumpered are marked with dotted lines. They are:
1 & 2
3 & 8.

There is no point in replacing the power diodes unless B+ appears weak or absent. You may find the large electrolytic caps are OK after careful re-forming. ALL paper caps should be replaced.

Rob/NYC

Thanks Rob........