It is an open secret that Pentax 6X7 and 67 don’t run without power. While their mirror and cloth curtains are mechanically driven, they are in fact electrically controlled by transistors and a magnet. A TTL prism finder also drains a battery if you forget to switch it off. The most common equivalents to PX28 are well-known alkaline 4LR44 and silver-oxide 4SR44 batteries. While you can find these batteries in some specialized stores, they are not universally available in case you’ll need them urgently.
Making 4LR44 replacement
And it happened to me once… I forgot to take batteries for both my cameras — Pentax 6X7 and 67 — on a trip and was unable to instantly find a 4LR44/4SR44 battery or its equivalent in the town I was staying. Fortunately, I managed to find four LR44 button cells instead of keeping in mind to fix them together with tape and use the whole set as a replacement.
It was a big success to find them so easily and quickly in a nearby store. These batteries are more common in local stores than 4LR44/4SR44. But they are also a bit longer than a set of four LR44/SR44 button cells. So, I needed a spacer of about 4-5mm long to be added to the set.
Considering “what to use as a spacer”, I found an iron screw-nut of similar diameter and about 7mm long lying on a street, which I used as a spacer. The set is 3mm longer than a standard 4LR44/4SR44 battery, but it is still possible to be used as a replacement for PX28.
Well, it was a good experience and the set sufficed for the entire month of shooting and I kept using it upon my return for some time. Honestly, it is better to use original 4SR44 or 4LR44 batteries. I will be happy if my tip helps you in a difficult situation. Wish your batteries never let you down and keep shooting!
P.S.
Thanks for reading! I would be very grateful if you point out my possible mistakes, add extra information, or just share your experience. Scroll down to the Leave a reply section and share your thoughts about it. Your opinion is important for me. I enjoy answering your questions as the answers may often benefit many other readers and the process of answering allows me to better piece together my existing knowledge and find ideas to improve my articles.
Aiman
Nice hack. Though, why can’t you put 5 lr44 instead of a nut?
Sasha Krasnov
Thank! As for your question – because 5xLR44 = 7.5V instead of 6V.
Ryan
Thank you so much for sharing this. I did the same thing today and it worked out perfectly.
Sasha Krasnov
That’s great Ryan! I really enjoy helping you, it’s my pleasure!
Boris Kolomytsev
Саша, отлично! Спасибо. Сегодня получил 67-й из Японии – не мог дождаться нужных батарей, и использовал твой совет. Работает!
Sasha Krasnov
Не за что! Главное, что все получилось!
Claudio Freitas
congratulations, Sascha !!!…It’s Really Awesome !!!!..Great tip !!
Sasha Krasnov
Enjoy 😉
Derminder
Useful info Sasha Thanks.
I have the same issue but the opposite way around.
My device uses 4 x 4LR44 batteries and I’m looking for a single cell equivalent.
The 4LR44/4SR44 are about 5-6mm too long.
Any suggestions for a single cell replacement would be appreciated.
Derminder
Sorry error in my description. My device uses “4 x LR44” batteries.
Sasha Krasnov
Sorry for the late reply. What seems to be a problem? Why not try fixing 4 x LR44 cells with glue tape? You can pre-make a set of these batteries and take to the long-distance travel.