Rangefinders with bridge circuits

[Russ]

Rangefinders with bridge Circuits.

I have read on numerous occasions, that quite a few of the older rangefinders have circuits that automatically compensate for voltage difference with batteries. Is this true? If so, are they listed somewhere?


Russ

 

[Dez]

I have not heard of one. For sure the Leica M5 and CL and Canon 7 do not have this design. Typically a meter with a bridge circuit will have the user centre a needle against a fixed index. I believe LED meters generally use this design.

Cheers,
Dez

 

[seany65]

My Ricoh 500GX seems to be one. I've got a silver-oxide 1.35v in and it seems to be working as it would with a mercury 1.55v.

 

[ptpdprinter]

My Ricoh 500GX seems to be one. I've got a silver-oxide 1.35v in and it seems to be working as it would with a mercury 1.55v.

The mercury batteries are 1.35v and the silver oxide are 1.5v.

 

[Beemermark]

The mercury batteries are 1.35v and the silver oxide are 1.5v.

And thus the reason his meter work's with the never silver-oxide.

 

[seany65]

😱 Thanks for the correction ptpdprinter.

Mind you a battery with a different voltage to the original can still work in it and produce readings that are 'correct' without altering the film speed, so I think it does have a bridge circuit.

Although I could be wrong.😱

 

[ChrisPlatt]

I don't know of any 35mm compact RF cameras with bridge circuits.

The vast majority of popular models were designed to use 1.35V
mercury cells, and won't meter correctly with modern batteries.
Users now can recalibrate meter, use adapters or adjust film speed setting.

A few mostly later models were designed to use 1.5V cells.

Chris

 

[monopix]

I don't know of any 35mm compact RF cameras with bridge circuits.

The vast majority of popular models were designed to use 1.35V
mercury cells, and won't meter correctly with modern batteries.
Users now can recalibrate meter, use adapters or adjust film speed setting.

A few mostly later models were designed to use 1.5V cells.

Chris

Yashica Electro RFs use a bridge cct.

Sent from my SM-G925F using Tapatalk

 

[charjohncarter]

I have not heard of one. For sure the Leica M5 and CL and Canon 7 do not have this design. Typically a meter with a bridge circuit will have the user centre a needle against a fixed index. I believe LED meters generally use this design.

Cheers,
Dez

The Bessa Models may have this, as there is a led matching system. Also, I do know that my Pentax Spotmatic (not an RF) has a bridge design.