SWTPC CT1024

While I was fooling around with my ASCI I decided to test the serial connection to my PC. The only thing I had available was my CT-1024 terminal with the optional serial board. This unit never worked when I got it. Thought it was its ancient and probably non functional PSU, but after hooking it up to a bench PSU same issues: 1) Unstable video display with large whitish band in the middle. 2) No response to keypresses. 3) Field of blinking ? marks if cursor is switched off, garbled one line of random characters up top if switched on. When I connected it to my PC running PUTTY via serial cable, I fully expected it to do nothing. But to my surprise, it generates a continuous stream of Js (punctuated by the odd H) on the PUTTY screen if the RECV switch is off. If I hit Break, it generates a whole bunch of Bs. If I switch the RECV switch ON, the Js stop but I can still generate Bs with the Break key. One thing I'm wondering now that I've switched power supplies and the video situation isn't cleared up.. I'm wondering if this thing was set up to connect to a composite monitor at all? I've seen pictures of the CT1024 with a Sanyo monitor just like mine.. but on the Sanyo it does the same thing it does on all the others. Anyway, thoughts/ideas welcome. Would love to get this thing running again.