Betapack2: Not Receiving Dmx

[yellowlemon]

Hi all,

 

I've got a Betapack 2 (wired 32A x 1) here, and it's being naughty... I hope you can help?

here are my observations so far:

• Powers up fine
• Desk supply LED is on
• O/P LED's all work
• Channel test buttons work (I've tested the outputs via these and a fresnel - nothing untoward here).
• DMX address set to 025 (correct for this install), also tried setting it to the same address as another dimmer to verify the behaviour. As expected, the fine dimmer was fine, the broken one was broken.
• Does not read the DMX...
• I've tried placing the unit as the first in the chain to no avail.
• Tried it being the only item in the chain, followed by a terminator...
• Checked my signal wiring - the signal chain is fine with the other dimmers (a mixture of Betapack 2 & 3's), and the selection of nodding buckets are all behaving too.
• Checked termination - all fine here too.
• there is one thing though: When I plug in the DMX, the error LED will flash once, maybe twice... And then go dark again? Hmm.

The only thing I haven't done yet is take it off of the wall and go hunting around for blown passive components on the control circuit. I've had a long browse of the manual, and can't find anything pertaining to this behaviour... Before I remove it from the wall, is there anything else I should investigate?


Thanks,

 

Mike.

[iank99]

Check the front panel screws... There's one on each side cheek of the rack that secures the front panel to the dimmer - the screws that do this are different lengths and the shorter one needs to be inserted at the end where the test buttons and DMX card are located.

 

What mostly happens is someone takes the screws out (for one reason or another) and reinserts them the wrong way around - the long screw pierces and damages the 5v track on the DMX I/F so the rack can't decode the DMX. You need to disassemble the rack and pop the test PCB section out and patch the tracks on the DMX I/F - whilst you have the test PCB out, check the analogue and DMX PCB for dry joints (especially around the molex connectors that connect the two cards together).

 

If this all sounds a bit beyond you - then your local repair centre (or me) could do this for you for about the cost of 1 hours labour at most.

[yellowlemon]

Thanks for the advice, I'll give that a go tomorrow morning when I'm next in the theatre.