Closed CBM Plus/4 support

I have just been given a plus/4 - used to have one and loved it but there is no picture - the tv tunes in but I just get a black screen so I bought a cbm - scart cable and nothing through that either - can anyone help?

Jayce

There are number of reasons causing black screen. Most probable cause is broken TED chip or CPU. Could be ROM, RAM or PSU as well. Did the power LED turn on?