My Yashica J-5
These are some scans I did of the Yashica J-5 I have. All images are thumbnails linked to larger versions: click on one for the larger version.
Unlike the TL and other series, this has the light meter cell on the outside of the body. I suppose the TL name came about with through-the-lens metering. This light meter is coupled to the shutter speed knob to the extent that changing the shutter speed moves the light meter needle and also a scale underneath with red areas marked at the ends.
The inner and outer circles of numbers on the light meter readout are both F stops, with the values on the inner circle fitting between the ones on the outer circle. There just isn't enough space to print all the numbers in one circle. I was confused by this and the dual ranges on the meter switch until I spent some time playing with it. One of the switches in this camera is a little dirty, affecting the readings, which made it even more confusing.
There seems to be some mystery about the older screw mount models. The first
Yashica SLR was the Pentamatic, released in March 1960, which was bayonet mount.
Apparently the first screw mount was the Penta-J in September 1961. From then on
there were various J-? models which apparently were screw mount, but between the
first Pentamatic and the Penta-J were the Pentamatic II (September 1960) and the Pentamatic-S (June 1961).
These two intermediate Pentamatic variations were probably bayonet mount (my guess).
(Some of this info from Yashica and some from a posting to the Yashica SLR Mailing
List by Eugene Goffredo).