I made two extension cables using crappy 6 conductor (3 twisted pairs)
telephone cable.

25 foot cable plus camera's 4 foot cable. Works.
40 foot cable plus camera's 4 foot cable. Does not work.

I also tested with an FTDI RS232 adapter, same results.

Thanks for everyone's input. I will get an active extension cable
sometime and experiment further, I suspect I'll be able to get 50 feet
with one active extension but I'll let you know.

Cheers,

Bob

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