Phonoland

Hi All

I have Rockola 464, the case the components aremounted in say “Rockola 48350-A Integrated Circuit” don’t know if that is the proper part No. for a 464 or some other model???

The 464 Amp Schematic shows a component 49125 driver board.

There is a bad driver board in this amp and it is marked as, part # 49079.

Is there anyone that is knowledgeable about Rockola amps that can shed any light on this or provide a schematic for this component 49079?

I have no idea if someone put a different model amp in this 464, or the difference in the schematic number and actual part number due to a production change????????

Any clarification about this will be greatly appreciated.

Best
Darrell

Darrell,
That schematic shows MANY different boards, and part numbers inside that amp--None of which look anything like the 49079
Ron Rich

Hi Ron

I understand that and hope that someone with knowledge of this rockola component will be able to tell me which model that amp component came out of or in the best case scenario provide a schematic for that exact component.

One can only hope

Best
Darrell

Hi
Looking at the schematic and the 464 machine i have at the moment, i don't see any board marked 49079, which board is it, is it power supply, cap, pre amp, amp driver etc, maybe if you could post a photo, as far as i know most parts of the rockola amplifier during the seventies were interchangable, from rockola 453 up to rockola 470
regards
clones

Clones

You are correct, the schematic for the 464 does not contain a part #49070 instead it shows driver #49125.

The part creates a severe hum when powered up. The component has had the caps replaced and now need to explore why the problem is still present.

I have looked at the 444, 445, 448, 449, 450, 451,(numbered in the 4500 series, 453, 454, 456, 458, 460, 461, 462, 465, 468, 470 (numbered in the 49100 series) 478 and 481 (numbered in the 52200 series) I do not think I will be able to find a schematic for part # 49079. Maybe it is out of a 452, 463 or 467 if there is such a machine, at least I can not find a schematic for them to check.

Best
Darrell

Clones,
Looking at it, my guess would be, it is the driver stage--looks like it has three transistors, and an adjusting pot (for the bias?). "Heat sunk" to a "driver transistor" (?) is a (dual ?) diode ? Un silk-screened, so I don't know what goes where--caps maybe incorrect--very suspicious of one that is larger then space allowed ?? Ron Rich

Ron

OOPS, you are correct, it is a driver and the correct part number as shown on the 464 schematic is 49125, I sill cannot find a driver board with the number 49079.

Best
Darrell

Probably best to replace it with the same driver board that drives the other channel, is the layout of the two driver boards the same, maybe take a photo and post it
regards
clones

Clones
This is the other driver board, which checks good. The part # is the same as the bad board.

Ron

As the large blue cap on the good board is in the same location I do not think there is a problem there.

Best
Darrell

Hi
I have attached the schematic for the rockola 49125-A driver pcb, looks the same at the one in your photos, i have a few driver boards of this type at home i will photograph and post later

Clones

Thank you, that is the same schematic I have. Just not sure if it applies to part #49079?
Appreciate your help.

Best
Darrell

Hi
I took a few photos of the spare driver boards I have and they are numbered at the front as 49125 and at the back as 49079-1, so the driver baord you have is the same as the schematic
regards
clones

Clones

Thank you. I see that my boards are 49079 and yours are 49079-1, is this becuse they made a minor change to the board and yours are a different production run?

Also, I see on yours the individual components are clearly identified, whereas on mine the parts are not identified, could that expain the part number change?

Also I do not see the 49125 part # on my boards, just the 49079 on the reverse side?

Best
Darrell

Darrell,
If like Seeburg--when some board went out without silk-screen--the answer was ALWAYS,
"the silk screener "F'd" up"--no one would ever admit who, or what, the "screener" was
Also, if like Seeburg the dash number indicates a minor change-- In Seeburg's case, MOST of the time, these boards are interchangeable. Ron Rich

I have a number of these boards, some are blank, some have the components labelled, any blank ones are not labelled 49125, i have interchanged these boards before without any issue they all fit the amps from the rockolas made during the seventies, they don't fit any other rockola amps that i know of
Clones