IanSB
commented
1 year ago @alanapplyby
Having a join or joins (an adapter is an additional join) in the cable between the Pi and the monitor can sometimes cause problems with signal reflections and the results can vary from monitor to monitor so you may find such a setup will work OK with a different monitor. Assuming that this isn't caused by another problem like shorted or intermittent connections in the cable assembly, there is a Pi setting which can help and that is the hdmi boost setting:
Load the config.txt file on the sd card into a text editor and find the following entry:
# Set hdmi signal strength. (Valid values are 0-11)
config_hdmi_boost=5
Change the value from 5 to a higher number and save back to the sd card. Reset / repower the Pi after each change If this fixes things, use the lowest value that works for you as higher values increase the risk of damage to the HDMI output drivers if there is a short circuit on the HDMI cable.
On my Amiga 600 all works perfectly if I plug an hdmi cable directly into my pi zero, however I get no signal if I run a ribbon cable to extended the femla hdmi socket in place of the original modulator.
I've tried 2 different ribbon cables, 2 different mini hdmi adpaters (which plug into the pi) and 2 different hdmi cable. The only bit I've not tried changing is the full size hdmi adpter which the monitor plugs into but I really cannot believe that this new item is defective. When I attach the ribbon cable the silver contacts are face down when I slide them in.
Anyone got any ideas?