(NEED HELP!) Atari 800XL error code? black screen?

[DEVSWZ]

It powers on, no video on screen, after a few seconds this plays. we have re-seated the socketed chips on the board and cleaned it.
any thoughts?

Video on : https://www.reddit.com/r/atari8bit/comments/fk0kkx/need_help_atari_800xl_error_code_black_screen/

 

[ahm]

I can hear the audio self-test, so the machine seems to be running.
We just can't see any video.

You may have an RCA male-male cable going from the 800XL's RCA jack to your TV's composite video input.
The 800XL RCA jack puts out RF, which needs to go to the TV antenna jack, typically using an RCA female to "F" male adapter. *
On the TV, select TV channel 2 or 3 depending on the position of the channel selector switch on the back of the 800XL.

* Composite video is available on the Monitor jack, but you need a cable with a DIN plug on one end and multiple RCA males on the other.
Often that cable goes missing, which is why I'm suggesting the RF method.
I prefer composite video instead of RF whenever possible.

Andy