Yashica's electronic-shutter M42 SLR — the TL Electro-X, TTL CdS metering, 1968.
The Yashica TL Electro-X was a 35mm SLR introduced in 1968 in Yashica's TL (through-the-lens) line, using the M42 screw mount. It was among Yashica's earlier bodies to pair an electronically controlled metal focal-plane shutter with a CdS TTL meter. It should not be confused with the plain Yashica TL Electro, a separate, later 1972 model with a mechanical cloth shutter and lower specification.
It is a 35mm SLR on the M42 (42x1) screw mount. The shutter is an electrically operated vertical metal focal-plane unit, stepless from 2 seconds to 1/1000 plus B. Metering is TTL using CdS cells, with over- and under-exposure warning lamps in the finder rather than a match-needle. Exposure is manual, and the finder has a microprism focusing spot. Because the shutter is electronically timed, a working battery is required.
It is a solid metal-bodied screw-mount SLR whose electronic shutter offers stepless speeds and long exposures unusual for its era, making it a capable general, student, portrait and landscape camera for anyone with M42 lenses. The warning-lamp metering is quick to read. The limits are its dependence on the electronic shutter and a meter designed around mercury cells.
Confirm the electronic shutter fires and times correctly at slow and fast speeds with a fresh battery, and check for capping across the frame. Foam light seals of this era perish, so inspect the door channels and the mirror bumper. The meter was designed for 1.35V mercury cells (now banned), so 1.5V alkalines shift readings unless compensated. Check the prism for desilvering; the M42 mount accepts many screw-thread lenses.