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After recently learning about the general differences between the early AP-9XX, aka Tom Cat amplifiers (DC tubes) and later AP-7XX (AC tubes) amplifiers, I thought I would compose and post a list of amplifiers used on some of the Electrolas and Radiolas. If you have or know the missing amplifier model AP numbers, or see errors, your input would be appreciated. I don’t know if Brunswick used the same amplifiers or not.


VE8-60: AP-997

Radiola 30: AP-997

VE9-2: AP-947
VE9-16: AP-736B
VE9-18: ???
VE9-25: AP-947A
VE9-40: AP-947
VE9-54: AP-772
VE9-55: AP-947A

Radiola 64: AP-777
Radiola 67: ???

VE10-51: (1st) AP-997, (2nd) AP-736
VE10-69: (1st) AP-9524 or AP-947A, (2nd) AP-736
VE10-70: (1st) AP-952Y or AP-997Y, (2nd) AP-736

VE12-15: (1st) AP-997C, (2nd) AP-736
VE12-25: AP-952

VE15-1: ???

104 Speaker: AP-851
105 Speaker: ???

Oh, I forgot my 25 hertz Canadian VE10-51 uses a AP-952C

Waynola wrote:After recently learning about the general differences between the early AP-9XX, aka Tom Cat amplifiers (DC tubes) and later AP-7XX (AC tubes) amplifiers, I thought I would compose and post a list of amplifiers used on some of the Electrolas and Radiolas. If you have or know the missing amplifier model AP numbers, or see errors, your input would be appreciated. I don’t know if Brunswick used the same amplifiers or not.


VE8-60: AP-997

Radiola 30: AP-997

VE10-51: (1st) AP-997, (2nd) AP-736
???

I can tell you the amplifier in a Radiola 30 is no where close to the same as those in the VE 8-60 or VE 10-51. I have a 25 cycle 10-69. All I remember is that it has 25 cycle painted on the power transformer. I think the letter after the AP-736 has nothing to do with the input frequency but whether or not it has the voltage diver for the radio chassis.

Sorry about listing the Radiola 30, my mistake. I have now provided this list with the AP numbers underlined of the ones know to be true by visual confirmation.

VE8-60: AP-997

VE9-2: AP-947

VE9-16: AP-736B

VE9-18: ???

VE9-25: AP-947A

VE9-40: AP-947

VE9-54: AP-772

VE9-55: AP-947A

Radiola 64: AP-777

Radiola 67: ???

VE10-51: (1st) AP-997, (2nd) AP-736

VE10-51 50Hz: AP-952C

VE10-69: (1st) AP-9524 or AP-947A, (2nd) AP-736

VE10-70: (1st) AP-952Y or AP-997Y, (2nd) AP-736

VE12-15: (1st) AP-997C, (2nd) AP-736

VE12-25: AP-952

VE15-1: ???

104 Speaker: AP-851

105 Speaker: ???

Waynola wrote:After recently learning about the general differences between the early AP-9XX, aka Tom Cat amplifiers (DC tubes) and later AP-7XX (AC tubes) amplifiers, I thought I would compose and post a list of amplifiers used on some of the Electrolas and Radiolas. If you have or know the missing amplifier model AP numbers, or see errors, your input would be appreciated. I don’t know if Brunswick used the same amplifiers or not.

Here are few to fill in

9-18.................AP-777C / SPU-35
9-54.................AP-777C / SPU-35
9-56.................AP-777C / SPU-35
10-51................AP-952 or AP-997
15-1 (Hyperion)......AP-947 (early with cone speaker)
Tuscany..............AP-952
Cromwell.............AP-950

Radiola 28AC.........UP-972
Radiola 30...........RPA-947
Radiola 32...........AP-832A
Radiola 64...........AP-777C / SPU-35

Power Amp............AP-935
Battery Eliminator...AP-937
"B" Eliminator.......AP-1080

The Hyperion had a version with a 104 speaker, probably same power unit used as in the Radiola 28. I have only worked on one of those models
The Radiola 67 SPU is very similar to the SPU-35 except it doesn't use the filter on the output tube and the B+ to the output tube is much lower, 335VDC vs 500VDC. I have a 67 but I can't see the model number, it's impossible to move it with those long spindly legs, has to be picked up.

The AP-736 was also known as the SPU-24

Brunswick units use RPA as their prefix


Chuck

Thanks Chuck, great info. I've condensed the info into the list below (note that the underlined amplifier numbers below have been verified on my machines).


VE8-60: AP-997

VE9-2: AP-947 (Borgia II)
VE9-16: AP-736B
VE9-18: AP-772 or AP-777C (SPU-35)
VE9-25: AP-947A
VE9-40: AP-947
VE9-54: AP-772 or AP-777C (SPU-35)
VE9-56: AP-772 or AP-777C (SPU-35)
VE9-55: AP-947A

Radiola 30: AP-947
Radiola 32: AP-832A
Radiola 64: AP-777 or AP-777C (SPU-35)
Radiola 67: ???

VE10-51: (1st) AP-952 or AP-997, (2nd) AP-736 (SPU-24)
VE10-51 (25Hz): AP-952C
VE10-69: (1st) AP-9524 or AP-947A, (2nd) AP-736 (SPU-24)
VE10-70: (1st) AP-952Y or AP-997Y, (2nd) AP-736 (SPU 24)

VE12-1: AP-950 (Cromwell)
VE12-12: AP-952 (Tuscany)
VE12-15: (1st) AP-997C, (2nd) AP-736 (SPU-24)
VE12-25: AP-952

VE15-1: AP-947 (Hyperion)

Power Amp: AP-935
Battery Eliminator: AP-937
“B” Eliminator: AP-1080

104 Speaker: AP-851 or AP-951
105 Speaker: ???

I updated the list below (and downloadable pdf below) with a correction for the VE 9-55 and added the Model 105's amp model number. I also verified the Radiola 30 amp model number.

Electrola Amplifiers:

AP-9XX, aka Tom Cat, earlier black amplifiers for DC tubes,
AP-7XX, later brown amplifiers for receiver’s AC tubes.

Radiola Amplifiers:
Some uses the same amplifiers as in the Electrolas, but are referred to as RPA, Recton Power Amplifiers.

Underlined amplifiers below have been verified on my machines.


VE8-60: AP-997

VE9-2: AP-947 (Borgia II)
VE9-16: AP-736B
VE9-18: AP-772 or AP-777C (SPU-35)
VE9-25: AP-947A
VE9-40: AP-947
VE9-54: AP-772 or AP-777C (SPU-35)
VE9-56: AP-772 or AP-777C (SPU-35)
VE9-55: AP-997A

Radiola 30: RPA 947 (according to the Service Notes, though I have seen an AP-947 in one)
Radiola 32: AP-832A
Radiola 64: AP-777 or AP-777C (SPU-35)
Radiola 67: AP-777 or AP-777C (SPU-35)???

VE10-51: (1st) AP-952 or AP-997, (2nd) AP-736 (SPU-24)
VE10-51 (25Hz): AP-952C
VE10-69: (1st) AP-9524 or AP-947A, (2nd) AP-736 (SPU-24)
VE10-70: (1st) AP-952Y or AP-997Y, (2nd) AP-736 (SPU 24)

VE12-1: AP-950 (Cromwell)
VE12-12: AP-952 (Tuscany)
VE12-15: (1st) AP-997C, (2nd) AP-736 (SPU-24)
VE12-25: AP-952

VE15-1: AP-947 (Hyperion)

Power Amp: AP-935
Battery Eliminator: AP-937
“B” Eliminator: AP-1080

104 Speaker: AP-851 or AP-951
105 Speaker: AP-966

Maybe this will add a little bit to what you already know.

Yeah let me magnify what Earl provides by pointing out the X suffix on some of them. The early 9-40 has the AP-947 amp and the regular horseshoe magnet driver, while the late 9-40 has the AP-947X amp and the electrodynamic driver. We’ve not yet found a schematic for the X version 9-40.

See the attached for more examples.

Peter,

According to the front cover of SB #1 Supplement 12/16/27 you and Earl posted, the schematic for the AP-947X is the same as the AP-947 but there is no choke and the output transformer is 25:1 versus 1:1.