InFocus Projector - Intermittent display due to Audio Frequency

[Audioplus]

A church is having an intermittent issue with their InFocus projector. Whenever a particular low frequency bass note is present, the picture on video display will shut down.

Initial idea is video cable termination and what other component within the projector might be a culprit?

Any ideas to trouble shoot is appreciated!

[tom66]

Re: InFocus Projector - Intermittent display due to Audio Frequency

Perhaps a problem with insufficient power supply to the projector and amplifier. When the amplifier draws too much current, the line voltage drops causing the projector to reset. Or, it could be mechanical vibration - cold solder joint etc.

[Audioplus]

Re: InFocus Projector - Intermittent display due to Audio Frequency

Hi Tom

Gut feeling is mechanical, I guess I could run a frequency sweep. I think there is a EQ in the audio system, might be able to filter that frequency out?
I'll have to check on the power supply idea as well, if they're using same circuit for audio & video.
As always, thank you! FYI, been in the A/V industry for 25 years, worn all kinds of hats, recently about 15% of my business is TV repair. www.audioplusidaho.com

[shovenose]

Re: InFocus Projector - Intermittent display due to Audio Frequency

Try placing the unit on a bettery backup UPS unit and then unplug the UPS. Then you will know it's not electrical

[tom66]

Re: InFocus Projector - Intermittent display due to Audio Frequency

If you do that, make sure the UPS is true sine wave; a lot of projectors can't ballast the bulb properly from the modified square wave output of some cheaper inverters/UPSs.