Model Railroading > DCC interference with TV camera?

We have a recurring problem with a camera used by our staging operator to see where to stop a train. The layout is DCC equipped and we have several radio throttles in use. The camera is hard-wired to the monitor with coax cable. The DCC is all NCE. The interference consists of nearly blanking the screen with diagonal white lines, but not all the time. There is no sound system for this monitor/camera combination.

Has anyone else encountered such a problem and definitely traced the cause to DCC equipment? What kind of measures can we take to reduce this problem?

Thanks in advance, Jeff Pape

It sounds like you have RF interference, radio frequencies inductively transferred to a parallel conductor (think antenna). RF usually enters on a faulty coax. Check that the shield (outer metal sleeve) is securely connected to the connector at both ends and is properly crimped or compressed. Make sure the connectors are fully seated at both the camera and the monitor. Also check that everything is fully grounded. This may not fix your problem but it will eliminate the primary cause of RF interference.

Good luck and Happy Holidays
Chet

mp_eagle Wrote:
-------------------------------------------------------
> It sounds like you have RF interference, radio
> frequencies inductively transferred to a parallel
> conductor (think antenna). RF usually enters on a
> faulty coax. Check that the shield (outer metal
> sleeve) is securely connected to the connector at
> both ends and is properly crimped or compressed.
> Make sure the connectors are fully seated at both
> the camera and the monitor. Also check that
> everything is fully grounded. This may not fix
> your problem but it will eliminate the primary
> cause of RF interference.
>
> Good luck and Happy Holidays
> Chet

Surge protector on the power supply for the camera wouldn't hurt either.

I agree - sounds like your coax is picking up interference. Make sure it's good quality coax and routed nice and far from DCC power wires. It also could be interference on the power supply lines to the camera - make sure you've got decent voltage at the camera when it's on, and make sure your camera power is routed away from DCC power.