Vintage WW2 miniature rotary converter.

[dr pepper]

Thought you guys might like to look at this.
I was given some old stuff and amongst it was 3 mini old 1942 rotary converters, 12vdc to 260vdc I think they were for military comms sets.
I put one together from the 3 and fired it up, and it works great.
Heres an interesting vid, 1940's technology meets my pc tablet.

 

[MikeMl]

Dynamotors, as they are called, were used in two-way police radios into the late fifties and early sixties...

 

[tcmtech]

I have a larger 800 watt one that goes from 24 VDC to 115 VAC 400 Hz.

 

[dr pepper]

I think the most exotic one I've come across also had a hydraulic pump at one end and a pulley on the other to drive something, pretty handy if you need power, hydraulics and motion.

 

[Reloadron]

Dynamotors, I remember them well. As a kid in the 50s and early 60s military surplus stores had them piled floor to ceiling. Here are more examples of them. Scroll down the page. Following WWII and Korea military surplus was a great way for the young aspiring ham radio operator to get great stuff at reasonable prices. To eliminate the need for dynamotors we would build power supplies. The dynamotors weren't very efficient. **broken link removed** The input is 12 VDC @ 9.9 A (close to 120 watts) and the output is 400 VDC @ 180 mA (about 72 watts). They were, however, little brutes. Nice video there dr pepper.

Ron

 

[tcmtech]

SOme years ago I pulled one out of our local scrap yard from a load of misc stuff they got from the local air base.

It was 115/230 VAC 60 Hz 1ph input to multi volt 400 Hz 3ph at something like 2 KW 115 or 3 KW 230 input. It was tagged as broke yet it was clearly still new and in its original crate and packaging never opened let alone actually broken.

I bought it for $10 as scrap electric motor value and resold it on eBay for around $1000!

A buddy of mine who has a large salvage yard has one massive three phase powered unit that is rated at something like 150 KW that weighs several tons!

 

[dr pepper]

Mine looks like those ron it has end caps, I can get brushes for them, one of my suppliers sells standard size brushes.
Its obviously designed to last it has ball bearings.
I think it'll probably gather dust rather than be used for anything.
I used to know a junk yard owner too, right next door but like a lot of businesses in the UK the goverment has hsut him down with legislation.

I have a couple of valve car radio's, these dont have a rotary, sorry dynamotor, they have a synchronous vibrator, and interesting device in itself.

 

[Reloadron]

Mine looks like those ron it has end caps, I can get brushes for them, one of my suppliers sells standard size brushes.
Its obviously designed to last it has ball bearings.
I think it'll probably gather dust rather than be used for anything.
I used to know a junk yard owner too, right next door but like a lot of businesses in the UK the goverment has hsut him down with legislation.

I have a couple of valve car radio's, these dont have a rotary, sorry dynamotor, they have a synchronous vibrator, and interesting device in itself.

Oh yes, those units were well built to say the least. I also went through my share of the old car radios that used valves (tubes). The vibrators were also slick as to a way to get the high voltage B+ for the valve plates.

Ron