Yes it was the Pentax M42. I had a few of those lenses as well.

The interesting thing is that the Miranda bayonet mount had to be fairly wide to wrap around the screw mount. The G had direct mechanical coupling outside the mount itself from lens to meter, I think. My 35 has the coupling but it doesn't latch onto anything on the F body.

The body had mirror lockup -- great for avoiding bounce in astrophotography. Also had a removable pentaprism for which a look-down hood and focusing screen could be substituted.

Oh, heck, why not double down with another $8.50 investment?

There are cheap T mounts newly made for Canon EF. I use one to mount my wife's 60D on my f/13.3 astronomical telescope (1000mm with 78 mm objective). https://www.ebay.com/itm/Neewer-Lens-Mount-Adapter-T-Mount-Adapter-for-Canon-EF-EOS-80D-70D-60D-60Da/382077668237?hash=item58f59a8b8d:g:n6QAAOSw8HBZErG0

Normally, on that scope, I mount my Pentax K3 -- using an old, old Pentax T mount.

Soligor, like a lot of lenses from my childhood, was quirky. I have a 35mm with T, made of very light, thin metal. Very contrasty and sharp, but not well corrected for field curvature and vignetting when used full-frame. Dropped it a few times but the thin metal bent a tad, protecting the lens itself. Bought it around 1969 for my Miranda F, purchased when I was in high school in 1963. All my Miranda-compatible lenses still work, as does the camera, EXCEPT for the 50mm that came with the camera. It would leak oil onto the aperture blades if left stopped-down when off the camera -- and I forgot a few times.

... and sometimes they still make good cameras. I have a 1962-purchased Miranda that works fine and takes M42 screw-mount lenses. My one original Miranda-mount 50mm is, however, a bookend -- that lens family was hobbled by internal oil leaks. Interchangeable viewers, too. One is a pentaprism with light meter, the other for waist-level viewing. I was in high school. It cost me 10 weeks' worth of part-time work.

The Minolta lenses do hold their value, and I can see why. I have four of them, from a late neighbor. MD mounts, so no electronics. I use them in the studio on an A6000, often with a simple, $12 tilt-mount (+/- 4 degrees), mainly for food photography. Because the A6000 is mirrorless, there's no extra transfer lens in the mount. These full-frame lenses of course have a huge sweet spot on the APS sensor, so no problem there, either.

Yup. Cordless electric shavers almost always can handle any voltage for charging. Never seen one that didn't. Corded shavers (remember those?) usually can as well, but not always. In the bathroom, there is often a US wall plug anyway.

The converter you bought is probably a transformer. You would know immediately, as transformers are heavy compared to the weight of your wall wart. Transformers are for appliances that need a lot of power, like irons or hair dryers, and that DON'T have a power conversion function built in. Transformers are NOT for battery chargers, cell phones and so forth. They can be dangerous to use with your wall warts and chargers for large camera batteries! Dangerous! I've worked and vacationed in 85 countries. It has been years since I've traveled with a transformer.

The little warts and free-standing camera battery chargers almost always are good for 100-240 volts. They have this flexibility (and light weight) because they are NOT transformers. They are "switched" or "switching" power supplies. The circuitry inside them adjusts automatically to produce a standard output -- usually 5V and 1 or 2 amps ("A") (or 1000 to 2000 milliamps, "mA") for everything but larger camera batteries.

I was there for a week in mid-October 2009 for a TV shoot (Life After People). You will have far more light than I did! There is not a lot of pack ice up there -- the islands are warmed by the Gulf Stream. But the contrast between the white glaciers and the dark sea was spectacular, both from the water and from high vantage points (easy around Longyearbyn). I did photograph a glacier calving (near an old Russian coal mine and submarine communications center), but it was almost sunset. We were on a small boat nearby.

I stuck mainly with normal and wide-angle lenses -- most usefully the 18-55 kit lens that came with my old 6 mp Pentax 100D, and my ancient 50 mm F/2 and (rarely) my 135 mm f/2.8. Also had several point-and-shoots. It all worked great even as temperatures fell. But I was using NMHD AA cells and alkalines, not lithium ion. Polarizers are handy as well. (I was the on-camera talent, accompanied by two local guides, a cameraman and a soundman.)

Longyearbyn (population 4000) is by far the largest settlement that far north on Earth. Only tiny frozen wasteland peninsulas in Russia, the tip of Greenland, and so forth extend into that latitude. The town is fun... people are friendly, broadband is good (the US Navy, ahem, laid fiber across from the Norway mainland). I have photos of what are probably the farthest-north church, tourist shops, skateboard half-pipe and (at the Russian mine) statue of Lenin on the planet. Also took pictures of the outside of the doomsday seed vault (it's up the hill from the road that connects the airport with Longyearbyn itself), and old coal mining machinery. The little harbor and old coal port are delightful. Catch the views with glaciers all around.

BTW, much of the Life After People footage was shot at the old Russian mine. The deep freeze protects what is now a largely abandoned settlement there from trees and rot. There were a half-dozen Russian caretakers on the site and we had permission in advance to be there. The coal layers in the whole region tend to be high up on mountains, so the conveyor machinery from coal to harbor is quite spectacular, especially if you get close.