Kodak Synchro-Rapid 800 shutter question

[Sanders McNew]

I just picked up a 101mm Ektar, set in a
Kodak Synchro-Rapid 800 shutter. The
shutter has a B but no T setting. Can
someone explain how to lock the shutter
open for framing and focusing?

Many thanks in advance for guidance.

[Oren Grad]

With apologies if this is obvious, but a locking cable release is one possibility.

[Dan Fromm]

I haven't had one in my hands for years, so don't trust my memory.

Is there a blade arrestor? Silver button sticking out if the side. If so, cock shutter, hold button in, press shutter release. Recock and press shutter release to close.