cmuseum

The Speedlite 244T was designed for T-series cameras but IMHO is compatible with A-series cameras including the AE-1 Program. I have no hard evidence for that claim but a number of indications: Both, the "sister models" Speedlite 277T and Speedlite 299T can - according to their user manuals - also be used with New F-1 and A-series cameras. Obviously, the physical hotshoe contact layout of A-series and T-series flash units is the same. According to service manuals the T50 and the AE-1 Program use the same reference voltage (VC) of 1.3V. With A-series cameras certain relative deviations from VC (+/- VC/16 per stop) are used for the flash setting the aperture value in the camera (not sure about T-series, though). Resistances/currents for flash ready (CCC contact) are the same. Last but not least: Just mounted a 244T to a AE-1 Program and flash ready is recognized, proper aperture values are set, flash fires and nothing burst into flames. Regarding ISO 200 films the 244T user manual says: Use only ISO/ASA 100 or 400 film with this flash. Other films cannot be used. Depending on the speed setting the images may come out over exposed or under exposed by one stop. This still may get you usable results but I'd avoid ISO 200 film.

Don't know if these detail was already discussed in the posts missing from this thread: There are two different versions of the ON/OFF switch. “Old” switch: “New” switch: EF 2119XX, O114, microprism, “old” switch EF 2448XX, O1216, microprism, “old” switch EF 2624XX, P... (numbers illegible), microprism, “old” switch EF 4002XX, Q1231, split-image, “new” switch EF 4208XX, Q628 (? – hardly legible), split-image, “new” switch

Can you rule out that the roll of film was bad or that anyone (not even you) has openend the back before the film was wound back?

I'd also consider a shutter issue more likely than a light leak. The shutter curtains run horizontally and uneven curtain movement could possibly explain the pattern you see. Remove film, remove the lens, open the back and look through the shutter from behind while firing. Does a curtain seem to move uneven? Do you have access to a shutter speed tester?

The shade is clipped and glued to the filter thread element. Pour small amounts of lighter fluid between the shade and the filter thread to dissolve the glue. You can also try warming up the filter thread element to soften the glue. Keep trying to turn the shade using a rubber wrench until it breaks loose. Then open the rear end of the lens. Carefully push out the shade from behind using a strong but soft tool (you don't want to scratch the inside of the barrel). I have simply cut something from a wooden ice cream stick. HTH.