MR-9 Adapter Questions

[dynachrome]

I have a few MR-9 adapters from C.R.I.S. and have used them successfully in a number of old film cameras which used the old mercury PX-13 batteries. This month I have had problems with the meters in two different Canon F-1 bodies with the same adapter. I tried various new 386 batteries and sometimes got low readings. I don't know whether the problems are with the meter cells themselves or with the adapter. Do these adapters which change the voltage from 1.5 or 1.55 volts to 1.35 volts ever malfunction or wear out? Does anyone know whether Ken Oikawa is still repairing Canon cameras and might be able to work on the meter of an F-1?

 

[benjiboy]

I have 2 Canon F1n's and use an MR9 in each as far as I'm aware they reduce the Voltage of 386 silver oxide batteries from 1.55 by two volts to the correct 1.35. I have never had any problems with them.

 

[btaylor]

Easiest solution, buy another one and see. At worst you have 2 adapters which are always handy to have.

 

[railwayman3]

I'd try out, and compare, the various adapters which you have and see if you can identify any faults in them or the bodies. I've used the adapters myself with no issues....I think that they are fairly simple electronic circuits with no moving parts, so perhaps not too much to go wrong compared with a camera meter ?

 

[shutterfinger]

Take a fresh battery and measure uts voltage with a VOM/DVOM. Put the battery in the MR9 and measure the battery voltage through it, a DVOM requires a 10K Ohm resistor be used to trigger the voltage dropping circuit.
The MR9 adapter http://www.smallbattery.company.org.uk/sbc_mr9_adapter.htm circuit can fail.

 

[dynachrome]

I ordered a new CRIS adapter today and will try it out as soon as it arrives. I also ordered fresh 386 batteries.

 

[rjbuzzclick]

You could also try cleaning the inside of the adapter with a cotton swap and something like Caig Deoxit or lab grade isopropyl.