So I have an AF1000 that seems to be blocking DMX from downstream devices when it's plugged in. Looking at the schematic, it shows that the relay should switch the dmx out to be driven by the line driver IC when it gets 5V. I verified that the relay is doing that, so I figured (since the AF1000 responds to dmx itself) the only thing it could be is the line driver. I replaced that chip, and in the shop, with no lamp installed, was able to get a trackspot connected downstream from the AF to respond to dmx whether it was plugged in or not. Assuming it was fixed, I took it back to the club I work at, put a lamp in it, and put it back up on the truss... and I'm still getting no response from downstream devices when the AF is powered on.
Would a lamp make a difference as to why DMX isn't passing through? I don't see anything in the schematic that makes me think that would be the case.
On the bench, when I plugged it in, there was 5V applied to the relay coil, and i checked the relay contacts to make sure it switched. It did.
I also checked the schottky diodes with a diode checker, and got an average diode drop (~.6V) accross them, so I think they're ok.
Any ideas?
Jeff
