Permanent upgrade/replacement for 1.35V mercury batteries - voltage regulator

It's also a verb.

D
It's also a verb.

  • 0
  • 0
  • 11
The Kildare Track

A
The Kildare Track

  • 10
  • 3
  • 97
Stranger Things.

A
Stranger Things.

  • 1
  • 2
  • 64

Recent Classifieds

Forum statistics

Threads
198,913
Messages
2,783,001
Members
99,745
Latest member
Javier Tello
Recent bookmarks
0

Chan Tran

Subscriber
Joined
May 10, 2006
Messages
6,822
Location
Sachse, TX
Format
35mm
So the user has choices...

-) use a Zn-Air cell, that deteriorates in short time after being activated (some advise to reseal it between uses)

-) use a Schottky diode adaptor/camera-modfication, with its shortcomings

-) use a complex regulator for ideal voltage stability, only as camera-modification, which needs a switch or to take out the cell between uses

There is another choice not too long ago is to use the real mercury battery. A guy in Russia was selling them but now due to the war I don't think you can get anything out of Russia any more.
 

AgX

Member
Joined
Apr 5, 2007
Messages
29,973
Location
Germany
Format
Multi Format
Yes, or use old cells found in cameras/meters. Very few of these I still find usable.
 

ic-racer

Member
Joined
Feb 25, 2007
Messages
16,549
Location
USA
Format
Multi Format
Sorry, late to the thread, but is the OP offering the PC boards for sale?
 

AgX

Member
Joined
Apr 5, 2007
Messages
29,973
Location
Germany
Format
Multi Format
-) use a complex regulator for ideal voltage stability, only as camera-modification, which needs a switch or to take out the cell between uses

In cases where originally 2 cells were used, a adapter using 1 Lithium cell might be made.
 

runswithsizzers

Subscriber
Joined
Jan 19, 2019
Messages
1,760
Location
SW Missouri, USA
Format
Multi Format
I am curious to know if any camera equipment manufacturers ever suggested any factory-approved solutions for their equipment which was designed to use mercury batteries? That is, did any companies like Canon, Fujica, Gossen, Nikon, Olympus, etc. offer to modify their gear to work with post-mercury batteries? Or did they train their service techs to do some factory-recommended modification?
 

BrianShaw

Member
Joined
Nov 30, 2005
Messages
16,533
Location
La-la-land
Format
Multi Format
I am curious to know if any camera equipment manufacturers ever suggested any factory-approved solutions for their equipment which was designed to use mercury batteries? That is, did any companies like Canon, Fujica, Gossen, Nikon, Olympus, etc. offer to modify their gear to work with post-mercury batteries? Or did they train their service techs to do some factory-recommended modification?

Gossen sold a voltage-reducing adapter to use a silver oxide battery. No longer available. It works great.
 
Last edited:

4season

Member
Joined
Jul 13, 2015
Messages
1,986
Format
Plastic Cameras
I am curious to know if any camera equipment manufacturers ever suggested any factory-approved solutions for their equipment which was designed to use mercury batteries? That is, did any companies like Canon, Fujica, Gossen, Nikon, Olympus, etc. offer to modify their gear to work with post-mercury batteries? Or did they train their service techs to do some factory-recommended modification?

Simple adapter sleeves, yes, from the likes of Minox, Kiev, Zenit, Alpa and others. But I'm pretty sure that no manufacturer has ever offered an active voltage regulator such as this.
 

ic-racer

Member
Joined
Feb 25, 2007
Messages
16,549
Location
USA
Format
Multi Format
Search eBay for "Stable625".

Found it, thank you.
Not sure where I'll use it right now as all my current 1.35v stuff runs fine on zinc cells, but it is a clever device and it will be nice to have one on hand to use in something I might buy in the future.

As I write this now I'm thinking of my Horseman film plane meter. It is pretty big so no issue placing a voltage regulator. It takes two batteries (one for high scale and one for low scale) and it would be a great project to convert to a single battery with 2 voltage regulators.
 

Philippe-Georges

Subscriber
Joined
Apr 11, 2005
Messages
2,674
Location
Flanders Fields
Format
Medium Format
Just to add some more information from Gossen (I suppose they know what/how to do it):
 

Attachments

  • Batterieadapter - Englisch.PDF
    16.3 KB · Views: 150

AgX

Member
Joined
Apr 5, 2007
Messages
29,973
Location
Germany
Format
Multi Format
It is a hull with double base and a diode inbetween.
 

AgX

Member
Joined
Apr 5, 2007
Messages
29,973
Location
Germany
Format
Multi Format
Something else...

Whilst for non-linearity de Gruijter explicitely advises not to use NiCad-cells (thus not going up, but instead going down with nominal voltage), this tinkerer did so nonetheless and to his own surprise found it usable in practice. He built his own charger.
 

BrianShaw

Member
Joined
Nov 30, 2005
Messages
16,533
Location
La-la-land
Format
Multi Format
Just to add some more information from Gossen (I suppose they know what/how to do it):

... and to supplement that...

 

AgX

Member
Joined
Apr 5, 2007
Messages
29,973
Location
Germany
Format
Multi Format
That is a surprisingly well-written advice.

What makes me wonder though is that in context with their own, late electrical-adaptor they explicetely state to be unable to instead modify their old meters to take modern cells.
Maybe this statement is related to their explicite statement not to repair their old meters (including those early digital ones).
 

qqphot

Subscriber
Joined
Jul 12, 2022
Messages
223
Location
San Francisco, CA, USA
Format
35mm RF
-) one may argue that a Shottky diode introduces additional non-linearity

-) that document referred to explicetaly has it about a modifaction of the camera, even dedicated to its metering drain. Thus it is not only about an adapter solution.

I feel like in almost every case it's good luck when the schottky diode drop approach works, because for every diode the nonlinear region (i.e., constant voltage drop) doesn't begin until a certain amount of current is drawn, and doesn't necessarily begin abruptly even then. So unless the meter mechanism draws a decent current there's usually some combination of constant voltage drop and current-dependent resistive drop. It seems like it works ok on some metering mechanisms and very poorly on others.

If I wanted to permanently modify a camera and there were an easy way to access switched power, such as on the Leica CL where it's only on when the wind lever is flipped outward, I'd definitely choose a fixed three-wire regulator for the much greater precision and the fact that it can be adjusted.

Without switched power, I don't think I'd choose this solution because the constant drain would irk me, even if it's quite minimal.
 
Last edited:

AgX

Member
Joined
Apr 5, 2007
Messages
29,973
Location
Germany
Format
Multi Format
De Gruijter advised to chose the diode depending on the current-draw of the meter. However that current, at least for photo-resistors depends on the illumination of the sensor...
But you indicate that the issue is even more complicated.
 

ic-racer

Member
Joined
Feb 25, 2007
Messages
16,549
Location
USA
Format
Multi Format
A question about the voltage regulator. Do you need to connect the ground?
 

BrianShaw

Member
Joined
Nov 30, 2005
Messages
16,533
Location
La-la-land
Format
Multi Format
It is available at B&H. Still made by Gossen for Luna-Pro meters.

Thanks for updating that post. I forgot to do that myself. Yes, Gossen re-released their adapter… great news for users of their old meters!
 

Bill Burk

Subscriber
Joined
Feb 9, 2010
Messages
9,314
Format
4x5 Format
I put one of Filip’s regulators in a Gossen Luna Pro, and I have a Gossen Luna Pro with factory adaptation.

It was an adventure rigging a switch (disk inserted switch from an old Zip drive) to engage mechanically with the needle trap lever because electricity routes three ways from the battery (there isn’t one “on” switch to piggyback).
 

ic-racer

Member
Joined
Feb 25, 2007
Messages
16,549
Location
USA
Format
Multi Format
On a typical 3-pole regulator, yes. It needs to reference somehow.

Yes, it is totally different than a Schottky, which is too bad. I was planning on installing the voltage regulator in an OM-1, but that camera has a positive ground.
Way too cumbersome to install as the voltage regulator would need to go between the metal battery cap and the battery.

OM-1 is pretty popular and I believe the Schottky is a tried-and-true solution. Just need to make sure I get the right one.
 
Last edited:

Chan Tran

Subscriber
Joined
May 10, 2006
Messages
6,822
Location
Sachse, TX
Format
35mm
A 3 pole regulator would draw current even if the camera is drawing no current. So you would have to remove the battery when you don't use the camera. A zener in parallel is also drawing current when not in use. It would draw at least the same as what the camera needs to operate. A zener in series does not but it only drops a fixed voltage thus the voltage of the battery that you use can be higher than what the camera needs but it has to be stable.
 

koraks

Moderator
Moderator
Joined
Nov 29, 2018
Messages
23,009
Location
Europe
Format
Multi Format
a positive ground.

Er?
Anyway, a camera doesn't really have ground as such, unless it's somehow grounded. Doesn't matter; there's always a virtual ground. That's all that's needed. I can see how it may be mechanically challenging to connect something inside a cameraut electrically, it's really no different from any other device.

A zener in series

That would be a really odd contraption.
If using a zener (which is a bad idea here to begin with), your use it in series with a suitable resistor, the load (camera) parallel to the zener and the virtual ground and top pole of the resistor connected to the battery.
If connecting a diode in series here it would typically be a Schottky, not a zener.
Zener diodes are generally pretty awful in terms of consistency and load regulation in an application like this. They're also wasteful because of the reason you described.

A 3-pole regulator makes good sense if it can be connected after an on/off switch. Otherwise it will indeed slowly drain the battery. How rapidly this happens depends on the regulator used.
 

ic-racer

Member
Joined
Feb 25, 2007
Messages
16,549
Location
USA
Format
Multi Format
Er?
Anyway, a camera doesn't really have ground as such, unless it's somehow grounded. Doesn't matter; there's always a virtual ground. That's all that's needed. I can see how it may be mechanically challenging to connect something inside a cameraut electrically, it's really no different from any other device.
Yes, the chassis or all the metal structures of the OM-1 are positive. The voltage regulator would need to go between the battery and the metal battery cap and of course ground to the negative wire coming off the battery holder.
So then one is back to trying to get the regulator between the case of the 386 silver cell and the larger adapter which contacts the metal battery cap. I don't know if anyone has succeeded in getting a voltage regulator in such a small place, but, indeed a diode fits there. But for the OM-1, a diode can more easily be placed on the negative wire coming off the battery, rather than needing to cram it between the positive case of the 386 silver cell and the battery adapter which contacts the metal battery cap.
 
Last edited:
Photrio.com contains affiliate links to products. We may receive a commission for purchases made through these links.
To read our full affiliate disclosure statement please click Here.

PHOTRIO PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Ilford ADOX Freestyle Photographic Stearman Press Weldon Color Lab Blue Moon Camera & Machine
Top Bottom