Camera companies are funny. If you look at any specific type of current camera you'll see that across several brands they're practically identical. Here is another example of a compact rangefinder from the 1970s which has very similar features to others we've seen such as the Yashica Electro, New Canonet QL17, Konica C35 etc. This one is particularly small, light, and cute, with a fast, sharp and beautiful Rokkor 1.7 lens. It's somewhere between the New QL17 and Konica C35 in size and features. Fully automatic, with an interesting 'Easy Flash' system that apparently adjusts the aperture as you focus, based on a guide number you set with an under-lens lever according to a table on the back of the camera (A,B,C,D, or E depending on the ASA and distance to subject). The auto-manual switch seems only to be for the flash setting. This is a fully automatic camera, you set the film speed and focus. The camera sets the aperture and shutter speed.
Super bargain this one ($14.50US), I'm thinking the Hi-Matic series is full of those oft-overlooked treasures that happens when everyone is set on finding a mint Canonet GIII QL17. I know I didn't really think of it, I don't really think of Minolta as a must-have camera (blasphemer! a cry from the back) but I have to say, this one is pretty sweet. Avoid the G if you're looking for a true rangefinder - it's strictly zone focus with viewfinder, like a basic point & shoot. The AF series is just like the Konica C35 AF series (they even look the same - black, ugly).
I acquired another Hi-Matic E at the local Goodwill for even less than the first one, it's actually a Hi-Matic ES which is a version made exclusively to be sold at K-Mart stores. The only difference is the lack of SLS film alignment system (who knows how useful it actually is anyway) and no Auto-Manual flash setting switch. A black plate covers this part of the back, which says 'Manufactured exclusively for S.S. Kresge company'. I've also seen a black version (like the black Konica C35) that looks pretty kewl. But I think they're R@RE!Battery followup
At first, two new 640KA batteries (current replacements for the PX640 mercury) did not get this camera working, so I suspected corroded wiring and temporarily set it aside. THEN, After letting it sit for a week or more till I got around to looking at it again, it sprang to life! I had left the batteries in the whole time. No, I'm not sure what that means. So of course I immediately shot a roll of Plus-X, half at ASA50 and half at ASA100 to check the auto metering. At one point the whole thing locked up and I had to take the film completely out, reset the wind lever and reload the film. Then it stopped working again. Turns out I was right the first time (see below), and on top of that the 640 replacements aren't the best choice either (see below below).
I've given it a nice surface cleaning and cleaned up the glass, and have done a preliminary light seal replacement (I may have to go back and readjust, it's a bit tight to close and the new seals are untested). Dental picks are especially useful removing the old seals on this one as the door channels are deep. I also used many toothpicks moistened with Windex. Make the rubber strips thin as the mating surfaces also run deep. Give yourself a good couple of hours. I usually put on a movie I've already seen for this tedious task. Followup: I did have to adjust the thickness of the new rubber door seals to get the back to close comfortably. String might have been a better choice for this one. I disassembled the top cap and cleaned the rangefinder glass (it typically fogs up after a while on these little rangefinders). HOWEVER, a peek under the bottom cap revealed my problem here - corroded wiring from old batteries left too long. I ended up having to replace a wire in there, the black ground wire which is the same one I had to resolder on the ES. That one works when the batteries are fresh, the original E appears to have a mechanical problem where the shutter release jams somehow. I'll get around to it eventually. Maybe.
Tips & Tricks
As suggested elsewhere I basically confirmed that when using 1.5v batteries, setting the ASA to 1/2 what your film rating should be results in better exposures. So shooting Plus-X at ASA 50 looked like normal exposures while those shot at ASA 100 looked underexposed by about a stop. Extra note: the camera has nice auto shutter compensation and the pictures I took by window light that ended up being EV 7-8 (I checked afterward with my Minolta IV F) came out fine. What happens is the red light comes on to warn you of possible camera shake but the shutter snaps meaning that the exposure was within range. I think if it's out of range it won't take the picture, as you see with some Olympus cameras.
SO while replacements for the obsolete PX640 batteries are indeed available, I found with further use that the alkaline 640KA are not sufficient for this camera. For best results you should find a way to adapt 1.5v silver batteries for use in this camera, otherwise the voltage for the alkalines drops off fairly quickly to the point where the camera becomes unusable. The Seiko ESF (not my favorite shutter BTW) like the ES (even worse?) is programmed to NOT take a picture if there isn't sufficient light or battery power to trip the electrically greedy shutter. Here's a way you can make your own 640-replacement spacer-holder. I've also heard other methods, I'm trying it with two springs taken from an older broken flash and some foam to fill the gaps, seems to work just peachy.