Braun hobby 100 Flash 1955

[Ruben.Vallinga]

Hello forum members,


I have this old flash purchased.
He works on mains, the battery is missing unfortunately.
does anyone know of you what the appropriate voltage of this battery?


Thanks!
in this link you can see the photos:
https://www.dropbox.com/sh/lnzl4oy3f5rdsrg/ld2jdmSn3L


my exususes for my bad english, I'm a Dutchman


Sincerely,
Ruben Vallinga

 

[Ian Grant]

The larger early flashguns I used had 12v lead acid batteries. I may have something in a BJP Almanac with details on this flash, I'll look tomorrow.

Welcome to APUG BTW.

Ian

 

[tkamiya]

Wow...

That's some seriously old equipment! A device labeled 32 in diagram and you have in your hand in two photographs is called a "vibrator" and is a mechanical device to create AC from DC. It was notoriously unreliable when new and probably more so now. Picture 28 shows the contacts are quite pitted. It, at minimum, require a good cleaning. When it fails, I don't think you can find a replacement. Likely, this device is used when the unit is in battery operation only - to step up and charge a large capacitor bank. I say all this because I am not sure I would recommend spending all that money to refit this with a new set of batteries.

Anyway, nice find and it will surely make an interesting project. I am just not sure if it's practical try to use this in portable operation.

 

[AgX]

I got the predecessor; similar neat outer, a bit less edgy. Technically different.
I do not have mine at hand, but if my memory does not fail it takes alternatively 4 round primary batteries or a rechargable battery-pack. Thus that would mean 6V.

In the manual (photo #2) two different lighting angles (50° and 70°) are depicted. How does that work?

 

[Mike Wilde]

I have a Braun Hobby EF300, or something like that, made circa 1967. Solid state oscillator.

It originally used 2 4V wet cell batterys. The manual shows little float ball tubes and filler caps like your item #26.

I found my ocillator worked (very slowly) on a 6V battery, and later once I knew the oscillator worked, and allowed the capacitor to reform, I ordered 4 2V gelled lead acid batteries (Hawker Cyclones) , and built a box under the flash pack to house them, as they did not have the same form factor as the original wet cell batteries.

 

[Ruben.Vallinga]

The larger early flashguns I used had 12v lead acid batteries. I may have something in a BJP Almanac with details on this flash, I'll look tomorrow.

Welcome to APUG BTW.

Ian

thank you! I've found what voltage should be on it.
That is 6 volts

 

[Ruben.Vallinga]

Wow...

That's some seriously old equipment! A device labeled 32 in diagram and you have in your hand in two photographs is called a "vibrator" and is a mechanical device to create AC from DC. It was notoriously unreliable when new and probably more so now. Picture 28 shows the contacts are quite pitted. It, at minimum, require a good cleaning. When it fails, I don't think you can find a replacement. Likely, this device is used when the unit is in battery operation only - to step up and charge a large capacitor bank. I say all this because I am not sure I would recommend spending all that money to refit this with a new set of batteries.

Anyway, nice find and it will surely make an interesting project. I am just not sure if it's practical try to use this in portable operation.

I was wondering what was number 32, so it is an alternating current generator, thanks!
The flash does not fire under 6 volts.
because the conductive contacts lost power. I thought it was a changeover contact.
I had it replaced with a changeover relay, it did not work.
Now I know why, it was not a changeover contact, but an alternating current generator. can you still get new?
hopefully it works well with a working AC generator

 

[Ruben.Vallinga]

I got the predecessor; similar neat outer, a bit less edgy. Technically different.
I do not have mine at hand, but if my memory does not fail it takes alternatively 4 round primary batteries or a rechargable battery-pack. Thus that would mean 6V.

In the manual (photo #2) two different lighting angles (50° and 70°) are depicted. How does that work?

that's right I'm already learned that it was 6 volt, thanks!


you can change the angle by the white head to rotate.
then, the lamp further forward or further to the rear

 

[AgX]

I thought of changing the position of lamp to alter the lighting angle, though I did not thought the bulb fixture could be turned.
My unit has to two electrical devices that have to be interchanged, you only show one, the hacking device.

 

[tkamiya]

I was wondering what was number 32, so it is an alternating current generator, thanks!
The flash does not fire under 6 volts.
because the conductive contacts lost power. I thought it was a changeover contact.
I had it replaced with a changeover relay, it did not work.
Now I know why, it was not a changeover contact, but an alternating current generator. can you still get new?
hopefully it works well with a working AC generator

No, that device is NO LONGER MADE. You see an orange blob at the top with wire hanging out? That is a coil. When energized, it swings the arm one way. Once it does, a small contact breaks connection and the arm swings back. When it swings back, contact makes again and the magnet gets energized so the arm swings again. It'll keep doing that.

It is supposed to vibrate and make noise. Buuuuuuuuuuuuuuuuuuuuuuuummmmmm....

If you are handy with electronics, you could make sure the contact is clean and the coil is intact. Then perhaps rebuild it yourself. I would not put hope on finding it new or even new-old-stock. I'm sorry, it's seriously old....

 

[AgX]

I'm more worried about the condensator. That is why I did not start up my unit yet. I once had the tiny RFI-condensator of my kitchenmixer explode... I would not like to experience that with a flashlight condensator. Maybe one should exchange any of those old ones with new ones. The newer are smaller, so likely there will be no problem with mounting.

 

[Mike Wilde]

Finding new electrolytics rated to the voltage needed to work in photo flashes can be a challenge. Vendors catering to vacuum tube equipment rebuilds comes closest, but they with voltage compatibility usually don't stock ones with large enought capacitance ratings.

His capacitors/condensors might actually be foil and paper in oil, rather than the moist paste of a modern electrolytic capacitor.

 

[Peter Simpson]

Replacement electrolytic capacitors may be found in the primary of a switching power supply (try disassembling an old PC supply for parts) -- they're usually rated for 600V and of fairly high capacitance.
wax/Paper and mica caps can be replaced with ceramics.

The vibrator is a device from hell -- you'll not find a replacement unless you're extremely fortunate. Their function in modern equipment has been replaced by a pair of transistors...

If I were rehabbing this flash, I think I would opt to replace the voltage converter with a switching supply. Just treat it as a "circuit block" and put a modern version in -- far less trouble in the long run and you would end up with loads of extra space as a bonus!

 

[AgX]

One should distinguish between standard capacitors as used in power supplies and those designed for flash discharging. The latter are available from the electronic industry via their dealers.

 

[E. von Hoegh]

I was wondering what was number 32, so it is an alternating current generator, thanks!
The flash does not fire under 6 volts.
because the conductive contacts lost power. I thought it was a changeover contact.
I had it replaced with a changeover relay, it did not work.
Now I know why, it was not a changeover contact, but an alternating current generator. can you still get new?
hopefully it works well with a working AC generator

There are solid state replacements for the mechanical vibrators. If the contacts in the old vibrator have pitted, there are problems in the associated circuitry. Contrary to legend, vibrators are reliable when used properly.

 

[pentaxpete]

I bought a 'Braun Hobby Automatic' unit for £14 in the Canadian Maple Leaf store near Iserlohn when I was there in Germany with the British Army in 1957 -- in England with all the Taxes they were over £39 !! It had a power pack held from the shoulder and had the 'Vibrator' and two small lead acid batteries and a mains lead -- I got a second flash head for it - some years later I was GIVEN another unit and later 'rescued' some more Braun Hobbys from a Photographer who was taking them to the Council Dump -- I cleaned off all the mud and dust and plugged them into the mains and they WORKED -- I STILL use several 1950's Braun Hobby units and an EF300 with extra flash heads -- all working off the mains only - no batteries available any more !

 

[tkamiya]

You think?

Usually, after the vibrator is just a plain transformer and after that, a rectifying and filtering circuit. There's not much goes wrong there other than plain aging of components...

I played with vibrators when I had a GE Progress Line transmitters configured for mobile use. As OP and myself obtained these devices well used and with unknown history, reliability is pretty much in doubt. It'll be fun to restore it and I'd do it. (in fact I did) Would it be reliable enough for me to trust it? no....

Can you still get solid state replacements?? I know they existed for a while when these devices were actively used after their manufacturers declared EOL. I'm curious now...

 

[E. von Hoegh]

You think?

Usually, after the vibrator is just a plain transformer and after that, a rectifying and filtering circuit. There's not much goes wrong there other than plain aging of components...

I played with vibrators when I had a GE Progress Line transmitters configured for mobile use. As OP and myself obtained these devices well used and with unknown history, reliability is pretty much in doubt. It'll be fun to restore it and I'd do it. (in fact I did) Would it be reliable enough for me to trust it? no....

Can you still get solid state replacements?? I know they existed for a while when these devices were actively used after their manufacturers declared EOL. I'm curious now...

The vibrators drove a transformer, and there were capacitors in the circuit to prevent the contacts pitting. The size of these capacitors is critical both for efficiency and long contact life.

There were synchronous vibrators, too - they had two sets of contacts and rectified the current from the secondary of the transformer.
The replacement was essentially a solid state multivibrator with two hefty transistors, one could be home made pretty easily.

 

[tkamiya]

You mean caps ACROSS the contacts?? I wish I kept my old GE.... that was a neat piece of history....

 

[E. von Hoegh]

You mean caps ACROSS the contacts?? I wish I kept my old GE.... that was a neat piece of history....

Yes, but the size of the caps is somewhat critical because they are also across the primary of the transformer. When everything is right, the contacts last a very long time and reliabilty is good. A huge number of car radios used vibrators. I have a Philco portable radio which uses a two volt lead acid storage battery to light the tube filaments and drive a vibrator supply for the plate voltage. The original vibrator is still good after nearly 75 years and the radio weighs about 25 pounds.

 

[Prof_Pixel]

One thing to remember about old flash units like this is they usually put a large voltage (perhaps a couple of hundred volts) across the camera flash contacts, which often led to pitting of the flash contacts. With newer cameras that have electronic components, the contact voltage can destroy the camera. Use such flash units with care.

 

[AgX]

I guess the joy using these in relation to flashlights of today quite bulky and heavy units lies in coupling with contempory cameras.
Somewhere on the net were figure for maximum voltagec to be applied to the flash trigger of some modern cameras.
A solid state switching device as interface would be the outcome where necessary.

Even the trigger capacitors in bulb flashlight could be harmful. They are of "quite" low voltage but deliver quite a current.