RockOla 481 Memory Loss

Hi,

I'm trying to help a friend who has a RockOla 481 Jukebox.

It plays the first selected song and once it completes the song, the juke then returns to it's resting position, it does not play any more selected songs (from memory).

It will only play 1 song at a time and loses all others stored in it's memory.

However, if I reject the song before it is complete (using the reject button) it will play the next song selected in the memory. Very strange!

I have tested the logic board (as advised in the manual) and it tests as it should.

Does anyone have any suggestions what may cause this problem or where to start looking?

Regards

Gordon.

Hi Gordon,
Himmmmmmmmmm----(thinking !)---- How in the world does the CPU know, WHICH, "reject switch", has closed ??
Both are wired in parallel ? I suspect that this MUST be a co-incidence ? What happens if you select several records, and use the reject switch, prior to any finishing ???
Is there a "battery" involved in this system ? If so, I would change it ! Ron Rich

Hi Ron,

Thanks for giving this some thought. To answer your question.......

If I select 5 records and use the reject switch (before the record is finished) it will play the next record from the memory.

This can be the second, third, fourth etc, it makes no difference and it will play the next record.

If I let any of the 5 selected records play to the end and allow jukebox to end the record, it does not play the next record (the memory is erased) and the record basket does one complete turn and returns to rest.

I am sure there is a battery somewhere, I just can't locate it. It must be soldered in place. I will find it and change it.

Thanks once again.

Regards

Gordon.

Hi
There's a battery underneath the turntable i think but this is to hold memory if machine is switched off, the problem is either the profit setter or logic board, i had a 477 with same problem and i replaced the logic board and it cured the problem
regards
clones

Hi Gordon,
That makes ab-sol-lut-ley no sense, to my tiny little brain ? --- I wonder if it is a "time/heat thing" ?----
Try this--Make a few selections, allow the 1st record to be placed on the TT, but lift the tone arm off for a few minutes, then use the "remote" switch and see what happens--I'm thinking it will now also miss all of the rest of the selections made ? If it skips the rest of the selections, try the same thing again, only use the trip-off switch, to see what happens--
If it misses selections, I am ASSUMING that either a battery, or a failing cap, is involved. I have no idea what, if any battery was used in that model, but the /Service/Parts, Manual should tell you -- Ron Rich

Hi Clones,
Are you SURE, it was "the same problem" ?? Are you sure it made a difference which "switch" was used, in your case ?
Ron Rich

Hi,

Thanks for the replies.

As this juke is at a friends house, I need to go there to test your ideas.

I will get there ASAP and let you know what happens. Probably early next week.

Regards

Gordon..

Yes Ron i had same problem, but i couldn't say for definite whether it would select the next record if i rejected the record playing, i didn't try that, my problem was that if you put in 2, 3, 4 or 5 selections it would only play the first selection and not the rest, it has to be something to do with the ic's on the profit setter or logic board, maybe i am suffering from memory loss
Clones

Hi Clones,
Since I "don't know" that computer system, but do know "others"--I still think it's a battery/cap problem, rather than an IC problem--But I AM ASSUMING !! Ron Rich

Gordo: I'm probably not your best source here, since my own 480 (same mech) has been my most frustrating project yet, but the problem you described reminded my of the testing procedures from the manual. In one or more of the tests, it states that you have to manually cancel selections (not using the tonearm cancel leaf switch), so if you look that up it might possibly aim you in the right direction.
As for the battery, this one's different than later models that can't function properly without the computer battery. This huge battery pack under the turntable is for retaining selections in case of power loss. Completely disconnecting it makes no apparent difference in my machine.
Patrick

Hi All,
Thanks for responding.
I had some time with the juke yesterday.
Patrick, I followed the procedure from the manual and tested the Logic Board. I manually cancelled the selections (as it advises) and it all worked as it should. It played the 5 records and returned to it's resting position.
For a short time after this the juke worked fine. It selected the correct records and kept it's memory.
However, it started losing it's memory again after about 30 minutes. Only if I let the record finish, if I manually cancelled the record, it played the next from memory.
I suspect Ron's thoughts about a capacitor may be the answer (but which capacitor?).
Also, I cannot locate the battery. I have a pretty useless manual and it only says the battery is located in the 'battery board' next to the turntable. (I cannot find any 'battery Board').

Another problem I noticed yesterday is that the 'Indicator Light'' (showing which number record is playing) fades in and out sometimes. Is it possible that this could be a power issue which may be affecting the memory??

Regards

Gordo

Gordo,
Got the parts book--battery should be shown there !!
That now sounds like a "heat" problem--I would check ALL "grounds" (OK-"Earths", to you ! )--everywhere for good conductivity-- Ron Rich

Thanks Ron...will do.

Gordo..

Hi
I have seen this happen before whereby the display fades in and out and i corrected by adjusting the -9.6 volts on the power supply, measure it first which is i think the pink wire and chassis-ground, there's a trimmer pot to adjust, its all detailed in the manual.
clones

Gordo: here's the dope on the battery pack( 52503)and battery board (52255A). They are located originally beneath a cover underneath the turntable. The board has one two-pin and one three-pin connector. If yours has been removed, as were both of mine, there should be a couple connectors dangling loose around there. The battery pack itself looks like five C-cell batteries wrapped together. I'd imagine these would do a lot of damage if (when) they leaked so that's probably why they don't show up on a lot of jukes after thirty-four or so years. In "The Operation of the Computerized Rockola Phonograph" book it states on Page 31 that the sole purpose of this battery is preserve selections during a power-off; this can hold for up to 36 hours. In normal operation, this is charging.
The Service Manual, on Page 16, points to the general location of this assembly, which is described in the Parts Catalog on Pages 14 and 36.
Earlier on this forum, Clones advised me of the probable effect (none) if these components were missing. I was able to get both parts on Ebay, and it made no difference. Didn't work before OR after. I'm still plugging away on mine. Good luck.
Patrick