Decca Prestomatic radios - UK Vintage Radio Repair and Restoration Discussion Forum

telstar · 14th Apr 2021, 2:31 pm

Hi. I have two Decca type Prestomatic radios, one with U.K valves, the other with U.S octals.
The U.K is the model PT/AC, but is the one with American octals a Brunswick variation, and if so what is the model number, and is there a circuit diagram & manual for that, please?
It will be interesting to find out.

Mike

telstar · 15th Apr 2021, 2:19 pm

Quote:

Originally Posted by telstar

Hi. I have two Decca type Prestomatic radios, one with U.K valves, the other with U.S octals.
The U.K is the model PT/AC, but is the one with American octals a Brunswick variation, and if so what is the model number, and is there a circuit diagram & manual for that, please?
It will be interesting to find out.

Mike

Here is a picture of the Decca PT/AC Prestomatic radio, in case anyone does not recognize it

Robint 47 · 15th Apr 2021, 2:24 pm

Mike Sorry never come across a prestomatic radio, in my time with Decca. B

Robint 47 · 15th Apr 2021, 2:31 pm

Mike ignore above post not sure what happened . In my time at Decca never come across one nor do i have any service info. But Decca did use the term Prestomatic when referring to a model with a push button tuner system as your photo shows. It maybe a chassis modified to take a push button tuner,any chance of internal view and valve line up it may jog a memory.
Robin

telstar · 15th Apr 2021, 2:32 pm

Quote:

Originally Posted by Robint 47

Mike Sorry never come across a prestomatic radio, in my time with Decca. B

Hi. Many thanks for your reply. These radios were made by Decca, and I have these listed in a book about radio companies and the valves used in their radios.

telstar · 15th Apr 2021, 2:33 pm

Quote:

Originally Posted by Robint 47

Mike ignore above post not sure what happened . In my time at Decca never come across one nor do i have any service info. But Decca did use the term Prestomatic when referring to a model with a push button tuner system as your photo shows. It maybe a chassis modified to take a push button tuner,any chance of internal view and valve line up it may jog a memory.
Robin

Hi Robin
I will send you a picture of the internals of the radio next time.
Mike

jonnybear · 15th Apr 2021, 2:38 pm

The service information is on the DVD or here https://www.service-data.com/
John

Hartley118 · 15th Apr 2021, 6:49 pm

Maybe the US Brunswick version was first.

Brunswick was acquired by Decca in the 1930s. With the acquisition came Harvey Schwartz, a brilliant business-oriented design engineer, who not only designed products such as the FFRR/XMS pickup head and the Deccalian high quality record player, but was also involved in the Decca Navigator system and the foundation of Decca Radar. It wouldn’t be surprising if Schwartz also brought over the Prestomatic design from Brunswick.

Martin

telstar · 19th Apr 2021, 2:20 pm

Hi everyone.
Many thanks for your help. I have the service information on the PT/AC model with the British valves, but not the data for the model with the octal valves (U.S).
On the assumption that PT stands for Prestomatic, then there is a radio with just PTM AC in my radio manufacturers book that has the valves that they used in each set. In this case, the valves used were 6P8G, 6U7G, 6R7G, 6V6G, 5Z4G. Wonder if this version with U.S octal tubes uses the same cabinet as the photo of the PT/AC that has the U.K valves, then it will answer my question? Of course, I will still require the service data for the octal valves radio.
One thing in common is that both have the tone control near the top of the radio.
Cheers
Mike

telstar · 13th May 2021, 2:15 pm

Hi. I have come to the conclusion that the Brunswick equivalent of the Decca PT/AC is model 39EH. This was covered by Trader 328 as a radiogram, but mine must be the table radio variation as I have been informed that they have similar power supply circuits.
Cheers
Mike

telstar · 27th Sep 2021, 2:21 pm

Hi. I have studied the circuit diagrams for the Decca PT/AC and the radio that I believed to be the Brunswick (that has octal valves). There is a small difference, in both models there are three MES lamps (two scale and one waveband indicator), but in the Brunswick manual only two scale lamps. Wonder if my second set is still a Decca PT/AC but modified circuit?

14th Apr 2021, 2:31 pm	#1
telstar Octode Join Date: Dec 2003 Location: Leeds, West Yorkshire, UK. Posts: 1,592	Decca Prestomatic radios Hi. I have two Decca type Prestomatic radios, one with U.K valves, the other with U.S octals. The U.K is the model PT/AC, but is the one with American octals a Brunswick variation, and if so what is the model number, and is there a circuit diagram & manual for that, please? It will be interesting to find out. Mike

15th Apr 2021, 2:24 pm	#3
Robint 47 Tetrode Join Date: May 2014 Location: Bridgnorth, Shropshire, UK. Posts: 51	Re: Decca Prestomatic radios Mike Sorry never come across a prestomatic radio, in my time with Decca. B

15th Apr 2021, 2:31 pm	#4
Robint 47 Tetrode Join Date: May 2014 Location: Bridgnorth, Shropshire, UK. Posts: 51	Re: Decca Prestomatic radios Mike ignore above post not sure what happened . In my time at Decca never come across one nor do i have any service info. But Decca did use the term Prestomatic when referring to a model with a push button tuner system as your photo shows. It maybe a chassis modified to take a push button tuner,any chance of internal view and valve line up it may jog a memory. Robin

15th Apr 2021, 2:38 pm	#7
jonnybear Octode Join Date: Nov 2010 Location: Cullompton, Devon, UK. Posts: 1,435	Re: Decca Prestomatic radios The service information is on the DVD or here https://www.service-data.com/ John

15th Apr 2021, 6:49 pm	#8
Hartley118 Nonode Join Date: Aug 2015 Location: Cambridge, Cambs. UK. Posts: 2,198	Re: Decca Prestomatic radios Maybe the US Brunswick version was first. Brunswick was acquired by Decca in the 1930s. With the acquisition came Harvey Schwartz, a brilliant business-oriented design engineer, who not only designed products such as the FFRR/XMS pickup head and the Deccalian high quality record player, but was also involved in the Decca Navigator system and the foundation of Decca Radar. It wouldn’t be surprising if Schwartz also brought over the Prestomatic design from Brunswick. Martin __________________ BVWS Member

19th Apr 2021, 2:20 pm	#9
telstar Octode Join Date: Dec 2003 Location: Leeds, West Yorkshire, UK. Posts: 1,592	Re: Decca Prestomatic radios Hi everyone. Many thanks for your help. I have the service information on the PT/AC model with the British valves, but not the data for the model with the octal valves (U.S). On the assumption that PT stands for Prestomatic, then there is a radio with just PTM AC in my radio manufacturers book that has the valves that they used in each set. In this case, the valves used were 6P8G, 6U7G, 6R7G, 6V6G, 5Z4G. Wonder if this version with U.S octal tubes uses the same cabinet as the photo of the PT/AC that has the U.K valves, then it will answer my question? Of course, I will still require the service data for the octal valves radio. One thing in common is that both have the tone control near the top of the radio. Cheers Mike

13th May 2021, 2:15 pm	#10
telstar Octode Join Date: Dec 2003 Location: Leeds, West Yorkshire, UK. Posts: 1,592	Re: Decca Prestomatic radios Hi. I have come to the conclusion that the Brunswick equivalent of the Decca PT/AC is model 39EH. This was covered by Trader 328 as a radiogram, but mine must be the table radio variation as I have been informed that they have similar power supply circuits. Cheers Mike

27th Sep 2021, 2:21 pm	#11
telstar Octode Join Date: Dec 2003 Location: Leeds, West Yorkshire, UK. Posts: 1,592	Re: Decca Prestomatic radios Hi. I have studied the circuit diagrams for the Decca PT/AC and the radio that I believed to be the Brunswick (that has octal valves). There is a small difference, in both models there are three MES lamps (two scale and one waveband indicator), but in the Brunswick manual only two scale lamps. Wonder if my second set is still a Decca PT/AC but modified circuit?