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[Nathan Salt]

Hey guys

Had a fairly simple job last night. Small PA in the room for a webstream in a Hair Salon. Right near Luna Park in Sydney.
6 Channels of ULX-d and this is what I was greeted with on power up



Did a quick scan annnnnnd

Well bugger

Powered through the show. Had a few dropouts from interference but nothing show stopping.
Transmitters were only 5m away from the whips.

Did a scan with workbench afterwards


Pretty crazy. I had thought about putting the transmitters into high power, but figured being as close as I was it would have just made the overloading worse with the interference.
Any one had this sort of experience?
Will try and go back there with some Axients and paddles and see if that makes any difference
Powered the rack up back at the shop and it was clean

[Jordan Wolf]

Hey guys

Had a fairly simple job last night. Small PA in the room for a webstream in a Hair Salon. Right near Luna Park in Sydney.
6 Channels of ULX-d and this is what I was greeted with on power up



Did a quick scan annnnnnd

Well bugger

Powered through the show. Had a few dropouts from interference but nothing show stopping.
Transmitters were only 5m away from the whips.

Did a scan with workbench afterwards


Pretty crazy. I had thought about putting the transmitters into high power, but figured being as close as I was it would have just made the overloading worse with the interference.
Any one had this sort of experience?
Will try and go back there with some Axients and paddles and see if that makes any difference
Powered the rack up back at the shop and it was clean

That’s a pretty high broadband noise floor, wow! That’s what it looks like when I deploy wireless mics on the top meeting floors of skyscrapers.

You might try padding down the antenna inputs 6dB-10dB and letting the receiver do its thing picking up the mic frequency, but I’d sooner try another freq. range with less congestion.

Were there any fluorescent lights nearby, or large video billboards on the building?

[Nathan Salt]

Didn't look for fluro's, don't think so. And didn't see any billboards outside.
Vivid is currently being set up across Sydney, but that sort of noise floor suggests something pretty close to where I was /shrug

How do you pad the antenna input?

[Jerome Malsack]

computers, Digital amps, LED lighting or video walls can also create the RFI.

[scottstephens]

computers, Digital amps, LED lighting or video walls can also create the RFI.

YEP!!! There is a digital player in the rack, try de racking that and moving it away. Start with the obvious stuff

scott

[David Pedd]

Increase the squelch?

[Andrew Broughton]

I've gotten that with LED walls, but usually not quite as high as that, and usually it's not across the entire BW! Wow.

[Ike Zimbel]

I've gotten that with LED walls, but usually not quite as high as that, and usually it's not across the entire BW! Wow.

There's been a few posts on here (or maybe the SynAudCon list...) showing that just plain old domestic LED light bulbs can produce that much noise, if they are cheapo bulbs with bad filtering in them.
-The rack worked back at his shop so it's not the CD player.
-You pad the antenna input with external, BNC pads (attenuators), like these:https://www.saelig.com/product/ADE041.htm or these:https://www.minicircuits.com/WebStore/dashboard.html?model=HAT-6%2B
Note that this reduces the overall sensitivity of the RX, but if you had put your Tx in the higher power setting, the net result would have been an increase in your signal-to-noise ratio.
-Increasing the squelch would only affect the amount of noise the RX let through when the Tx was off. Once the receiver "opens up" for the transmitter, the RF noise floor is still high.

[Dan Currie]

I've gotten that with LED walls, but usually not quite as high as that, and usually it's not across the entire BW! Wow.

This reminds me of a concert I did for the opening of a clothing store.  All levels on the UHFR were pegged.  The source of the increased noise floor was the stores track lighting.

[Ike Zimbel]

This reminds me of a concert I did for the opening of a clothing store.  All levels on the UHFR were pegged.  The source of the increased noise floor was the stores track lighting.

That reminds me, I forgot to mention filters. Here's some info about that from the RF Venue site:https://www.rfvenue.com/blog/led-lighting-may-be-lights-out-for-your-wireless-mics?utm_medium=email&_hsenc=p2ANqtz-9d3kq189Po_tp5-wWHshLMz_-o6CcsnGITKd14zinr8h7nGW87ycK3wmVKp0OlXkQ8a4R9iNiGzzNd5QLMnYsd4_bV_A&_hsmi=61673985&utm_content=61673985&utm_source=hs_email&hsCtaTracking=9ad12e65-6b97-4785-8ed5-d9fe0c00b3a9%7C2aa4be1b-c5a8-4cc4-9f54-527548537422. Lectrosonics also sells band-specific filters, and Professional Wireless sells 470-616 MHz ones http://www.professionalwireless.com/product/uhf-in-line-filter-new-range/

[ProSoundWeb Community]