Share: Pre 1935, Vintage Rotory Transformer

[Kurtisinger]

TL;DR Summary

Newton Brothers (Derby) Rotory Transformer: type 28

Thought I'd share this interesting old relic as I am unable to find any information about "type 28" on the Internet.

 

[tech99]

It looks like an aircraft transmitter high tension supply, 1200 V at about 400W. This would suite an 813 PA valve. On the other hand 12V is unusual for aircraft and I wonder if it was used in a workshop.

 

[Kurtisinger]

It looks like an aircraft transmitter high tension supply, 1200 V at about 400W. This would suite an 813 PA valve. On the other hand 12V is unusual for aircraft and I wonder if it was used in a workshop.

12 volt DC in and 1200 volt AC out?

 

[tech99]

Yes, AC output looks wrong for an HT supply.

 

[Kurtisinger]

Yes, AC output looks wrong for an HT supply.

Interesting.. would think it would be 32v in, in those days.

 

[Baluncore]

Rotary Transformer Ref No 10K/21 s/n 1822;
Input 12V, 32 amps; Output 1200 volts 0.2? amp;
Newton Bros. (Derby) Ltd.

You will find references to the later Type 31 made for the RAF in 1940.

Your Type 28 example does not have the broad arrow that identifies government equipment.
The initials A M, either side of the crown suggests an English telegraph company, with appointment by the Crown. What is written on the crown x+y ?

It looks to me like it is a DC to DC converter. I suspect it generated high voltage for wireless telegraphy.

" Founded in 1899, Newton Derby has a long history of delivering generator solutions for technically demanding projects around the world.
The company was founded by the Newton brothers and one of the brothers, Mr Frederick Newton, had continued involvement of designing generators for aircraft in both world wars."
https://Newtonderby.co.uk/about/history/

 

[Kurtisinger]

Rotary Transformer Ref No 10K/21 s/n 1822;
Input 12V, 32 amps; Output 1200 volts 0.2? amp;
Newton Bros. (Derby) Ltd.

You will find references to the later Type 31 made for the RAF in 1940.

Your Type 28 example does not have the broad arrow that identifies government equipment.
The initials A M, either side of the crown suggests an English telegraph company, with appointment by the Crown. What is written on the crown x+y ?

It looks to me like it is a DC to DC converter. I suspect it generated high voltage for wireless telegraphy.

" Founded in 1899, Newton Derby has a long history of delivering generator solutions for technically demanding projects around the world.
The company was founded by the Newton brothers and one of the brothers, Mr Frederick Newton, had continued involvement of designing generators for aircraft in both world wars."
https://Newtonderby.co.uk/about/history/

Sorry, I'm not to sure what you mean by: What is written on the crown x+y ? I don't see any writing on the crown.

 

[tech99]

Sorry, I'm not to sure what you mean by: What is written on the crown x+y ? I don't see any writing on the crown.

AM means Air Ministry.

 

[Kurtisinger]

AM means Air Ministry.

Oh.. Thank you. So some aircraft must have had 12v. I picked it up with a pile of 32 volt motors that I have yet to catalog.

 

[Baluncore]

The 12V DC input was used to generate the HT for vehicle mounted radio transmitters, or for battery backup when AC power was not available.

 

[Baluncore]

@Kurtisinger
How do you know it is a pre 1935 ?

From; History of Telegraphy, by Ken Beauchamp. Page 299. (Start of WW2).
"The requirements of combined operations with airborne formations led to the production of a transportable medium-range transmitter, the Type 76, mentioned earlier, which could be dropped by parachute or transported in a light vehicle. This operated in the 2–12MHz band and was designed for CW Morse transmissions. It was one of the first British military sets to make use of a crystal oscillator to provide up to six fixed transmission frequencies which, by appropriate anode tuning in the power amplifier, could be doubled to give twelve spot frequencies from the fundamental and second harmonic of the crystal oscillator. This type of ‘spot frequency set-up’ was valuable for mobile use when fully trained operators were not available. It was normally used as a battery operated transmitter from a 12 V supply, its HT supply provided by a rotary converter, but provision was made for mains operation in a suitable fixed station location. The receiver normally associated with this transmitter was the Type R109a, an eight valve superhet covering the same frequency range of 2–12 MHz and with a vibrator supply unit [38]."

From; https://www.qsl.net/g4bxd/uk.htm
"The British R-109 receiver, used with the WS 76 Sender, used by airborne forces, in Arnhem etc," ...

 

[Kurtisinger]

@Kurtisinger
How do you know it is a pre 1935 ?

From; History of Telegraphy, by Ken Beauchamp. Page 299. (Start of WW2).
"The requirements of combined operations with airborne formations led to the production of a transportable medium-range transmitter, the Type 76, mentioned earlier, which could be dropped by parachute or transported in a light vehicle. This operated in the 2–12MHz band and was designed for CW Morse transmissions. It was one of the first British military sets to make use of a crystal oscillator to provide up to six fixed transmission frequencies which, by appropriate anode tuning in the power amplifier, could be doubled to give twelve spot frequencies from the fundamental and second harmonic of the crystal oscillator. This type of ‘spot frequency set-up’ was valuable for mobile use when fully trained operators were not available. It was normally used as a battery operated transmitter from a 12 V supply, its HT supply provided by a rotary converter, but provision was made for mains operation in a suitable fixed station location. The receiver normally associated with this transmitter was the Type R109a, an eight valve superhet covering the same frequency range of 2–12 MHz and with a vibrator supply unit [38]."

From; https://www.qsl.net/g4bxd/uk.htm
"The British R-109 receiver, used with the WS 76 Sender, used by airborne forces, in Arnhem etc," ...

Because the name of the company changed in 1935 according to their website.
https://Newtonderby.co.uk/about/history

 

[Baluncore]

I think you probably have a device from WW2.
https://www.gracesguide.co.uk/Newton_Brothers
The name changed in 1935 from what to what ?
But the pictures show the name “Newton Brothers (Derby) Ltd” was used in 1946 and 1961.

 

[Kurtisinger]

I think you probably have a device from WW2.
https://www.gracesguide.co.uk/Newton_Brothers
The name changed in 1935 from what to what ?
But the pictures show the name “Newton Brothers (Derby) Ltd” was used in 1946 and 1961.

I think I got the idea that they changed names in 35 from Grace's. Looks like Newton Derby is still operating today but they have a sister company called: Winder Power that's been in business for a long time.

It has an variable resistor on board, I wonder if that was to fine tune the transmission. Also it looks like somebody customized it to run off of 32v and put out 110. I wonder what the brush hanging off of one of the coils is for.?

 

[tech99]

The aircraft transmitter T1154 had a rotary transformer which looks very similar and called type 29. It gave DC output 1200 Volts 200mA from 12V. There is some information here, especually a pdf of the handbook: https://vk2bv.org/archive/radio/r1155.htm

 

[Kurtisinger]

The aircraft transmitter T1154 had a rotary transformer which looks very similar and called type 29. It gave DC output 1200 Volts 200mA from 12V. There is some information here, especually a pdf of the handbook: https://vk2bv.org/archive/radio/r1155.htm

Excellent, thank you..

He mentions that it's post war 1946. But hasn't been able to find much information about the manual. I sent an email to Newton Derby this morning, hopefully they have some information available.

 

[dlgoff]

Summary:: Newton Brothers (Derby) Rotory Transformer: type 28

Thought I'd share this interesting old relic as I am unable to find any information about "type 28" on the Internet.

I'm curious. Are you planing on cleaning it up and/or restoring it? A real beauty IMO. Thanks for sharing.

 

[Kurtisinger]

I'm curious. Are you planing on cleaning it up and/or restoring it? A real beauty IMO. Thanks for sharing.

Hi digoff.. I was thinking that I would try to reunite it with the proper caps. Otherwise it appears to be in pretty good condition, bearings are snug and turn well. So far I think the only other thing that it's missing is one of the grease nipples.

 

[dlgoff]

I was thinking that I would try to reunite it with the proper caps.

Sounds like a little restoring is going to happen. Let us know how that goes. :)

 

[Baluncore]

Maybe the coils and capacitor are a Twin T filter to keep RF out of the supply.
Is the variable resistor part of a voltage regulation circuit.
Does the spare brush fit either end of this unit?

How was it modified from 12 V to 1200 V; a factor of 100.
into 32 V to 110 V; a factor of only 3.4 ?

 

[Kurtisinger]

Sounds like a little restoring is going to happen. Let us know how that goes. :)

Will do..

 

[Kurtisinger]

Maybe the coils and capacitor are a Twin T filter to keep RF out of the supply.
Is the variable resistor part of a voltage regulation circuit.
Does the spare brush fit either end of this unit?

How was it modified from 12 V to 1200 V; a factor of 100.
into 32 V to 110 V; a factor of only 3.4 ?

That is a very good question. There is some information in the pdf that tech99 gave a link for about radio interference from the power supply but I just skimmed it briefly. Most of it is over my head. There are three variable resistors on it. One on the cord coming from 32v, and another dial that it runs into, and then there is a slider on the side of the board.

Looks like the brush hanging off the side is the same size.

 

[Rive]

Sounds like a little restoring is going to happen.

Well, I too value old electronic/electric equipment, but in this particular case I think a restoration (followed by trial runs, of course) would be a bit dangerous, so unless it is supported by sufficient knowledge about high(er) voltages I'm against it.

 

[Kurtisinger]

Well, I too value old electronic/electric equipment, but in this particular case I think a restoration (followed by trial runs, of course) would be a bit dangerous, so unless it is supported by sufficient knowledge about high(er) voltages I'm against it.

I don't have any intentions of plugging it in, even if it only puts out 110v. It's just way to rare to be foolishly blowing up. Could probably figure out if it's a working machine with a meter alone and a little input from the people on these forums anyway. If there were a lot of them kicking around I'm pretty sure I would though.. : )