Hi,
I have had one of these since new, so about 35 years. It won various awards. It is actually sitting next to me now, I have been testing the shutter speed accuracy (all spot on btw)
Mine came with the special edition Olympic lens cap.
It was designed to be simple to use, hence the lack of features, just program, Tv, manual, wide & tele mode. I found it had a tendency to give washed out colour photos, especially when I humped it all round the USA whilst on a fly-drive holiday. This I think is due to the metering system & not being able to add any exposure compensation for the bright sunny US summer.
Using slide film in the UK gave stunning colours.
It has an internal battery, under the prism. This keeps the frame numbers & ISO when the AA batteries are changed.
It took me years and years to find out how to get to the battery, which was 'designed' not to be user-serviceable.
Remove the lens, loosen the screws of the back latch, but do not remove.
Undo the screws on the front of the camera and remove the front.
This will now reveal the screws holding the top on.
Remove these screws and the top.
The battery will be seen, soldered to the board.
I checked the voltage, it was still good after 30+ years, so I left it alone.
To check the internal battery, either put in an old film cassette, or carefully wedge down the film-loaded button with some tissue.
Close the back, set ISO to something other than 100 and fire a few frames.
Remove AA batteries for a while & re-insert. If ISO and frame counter still set, internal battery is all ok.
The manual has a warning about the top LCD only lasting a few years. LCDs were quite new in those days. Mine is still 100% fine & most I have seen on ebay still look ok.
The databack is a different story. Most I have seen, including mine have bled.
As others have said, the body is plastic, so be careful, especially with the back release and battery cover. Spares are 100% unavailable without breaking another camera.
I am very careful with the battery door, which needs some force to close against the battery spring tension. I carefully close it, using even pressure, so as not to over stress the hinges and also operate the release catch manually, rather than just pushing the door closed. Similarly when opening, I slightly push the door to release pressure on the catch before releasing it and carefully open the door, not allowing spring pressure to fling it open.
Leaking batteries have killed many a camera. Rechargeable batteries do not seem to leak, unlike the disgusting Duracells.
I personally never leave batteries in cameras (or anything) for an extended period.
Don't know if leaving a film in the camera without batteries will discharge the internal battery.
A camera without film or batteries does not seem to deplete the internal battery, if mine is anything to go by.
Enjoy your T70

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