Help with a Pentax Spotmeter & battery

[scorpio516]

I've got myself an old Pentax spotmeter - possibly an original, I know it's from before the III. It's one of the ones with the 9v + another battery.

Now for my confusion: everything says it's an old mercury button cell. Before I go out and buy a Cris adapter or some hearing aid batteries, I've got to make sure. The compartment seems WAY too deep for a button cell - it's over 1/2" deep, covers up the 'n' in Energizer on a AA battery (attached picture)!

[Gem Singer]

It takes multiple mercury cells that are no longer available. They are stacked in the battery chamber. That's why it appears to be deep.

See if you can obtain a copy of the instruction booklet. Perhaps there is an adapter available so that alkaline or silver batteries can be substituted.

[Marc B.]

Scorpio, If your meter is anything like my "Spot V" meter, I believe it takes a stack of three (3) button cell batteries, Check out the manual at the Butkus Orphan Camera Site

http://www.cameramanuals.org/flashes...potmeter_v.pdf

[RichardRitter]

Your meter was last made 30 years ago. It take a 9 volt and mercury batteries no longer available.

More then likely the photo cell is very red sensitive this happens to the cells used in this meter.

[gari beet]

This is the battery that fits, I assume you can get them in the US. It would be pretty easy to get some posted if not.

http://www.lbslondon.co.uk/batteries...a-alkaline.htm

I have the same meter, still very accurate despite its age.

Gari

[jonathan_lipkin]

I had a meter like that once but gray. On mine, as I recall, the battery compartment opened and you took out a small assembly that held three lr44 batteries.

[scorpio516]

This is the battery that fits, I assume you can get them in the US. It would be pretty easy to get some posted if not.

http://www.lbslondon.co.uk/batteries...a-alkaline.htm

I have the same meter, still very accurate despite its age.

Gari

That's it! I don't know if I'll be able to find it locally, but I found some mail order options.

That's what confused me, the 640 battery is over 11mm deep.

I also found that it's an original Ashai Pentax/Honeywell Spotmeter 1/21, at least 2 generations behind the III

[scorpio516]

Just an update: it does not take the 640. I found one locally, and it still didn't work. The 1/21 manual says a 640.

I was looking on KEH at the meters they had, and they listed the Pentax 1/21 to use 2 x 625 . Found a couple of those the same place that had the 640, and lo and behold, it works! I haven't taken the time to see if it's accurate yet, but to find that it is mechanically intact made me happy after spending a week or two looking at what 80s/early 90s vintage spot meters are still selling for.

[Navy Moose]

Scorpio, If your meter is anything like my "Spot V" meter, I believe it takes a stack of three (3) button cell batteries, Check out the manual at the Butkus Orphan Camera Site

http://www.cameramanuals.org/flashes...potmeter_v.pdf

Thank you for posting this link. I downloaded a manual from Pentax and it was a terrible reproduction. The OP was timely in posting his question, this weekend I swapped out my batteries and I thought something was wrong because it took a while after putting in three new LR-44s for it to start functioning.