Unknown Yashica hammer-head flash...

It looks identical to the Yashica Pro 100 mentioned in a previous post, although the nameplate is a bit different. Oddly, that one is still for sale on ebay with only the flash unit itself and no bracket - but it does have a series of photos showing the battery setup.

Do a google IMAGE search for "Yashica Quick Lite Pro" and it appears as a 100.

Thanks guys for the info.

Looking at the piccies of boxed sets, it seems that the Quick Lite Pro-100 came in two forms - one with a single horizontal flash tube and another with 2 vertical tubes, presumably producing an identical GN. Mind you, it still doesn't help me to remove the battery box which won't budge....

Looking at one photo that seems to give the best perspective of the open battery compartment, the battery tray seems to slide into a metal box, and on the underside of that pull-out carrier, it shows the matching threaded pieces of the carrier and the head. What I assume is the usual circular guide legend that spins around, looks to have a 'screw head' at its center that holds the carrier in place -but- there's no photos that shows whether there's anything more than some knurled edges on that thumbscrew piece... like a coin slot or 2 holes for spanner pins.

If there's nothing to hold onto mechanically to break the corrosion seal from badly leaked batteries, then the only option might be chemical. I used a small plastic chip-dip tub with a 1/2 inch layer of undiluted white cider vinegar as a solution to get the carrier of a Honeywell hammer flash unstuck, with no ill effect on any metal or plastic body pieces. It was left sitting overnight, and it took no pressure or prying to get it apart after a good soak.

Thank you for the advice guys.

I was eventually able to use brute force to unscrew the flash calculator and prise the battery box out. As feared, batteries had been left in, then later removed but the corroded terminals and metal plates were left untouched. I have not a clue as to whether the acid reached into the main part of the flash; no doubt the moment I switch on the mains supply will tell me (and the main fuse at home) if the circuitry is damaged. Meantime, I'm going to try to clean up the battery box using a combination of fine wire-wool, DeoxIT, and electrical paint...