Blackmagic Forum

Hi together,

this evening after using the pyxis already 3 weeks I had massive frequency problems.

I filmed in an university where an event was happening and the sound from stage crashed with something that has to do with the pyxis because when pyxis was turned off there were no audio problems. After the event I tested a lot of things where all other signals where turned off and it is 100% the pyxis fault.

So the question is what signals do the pyxis send beside bluetooth (was turned off)?
The audio hand microphone was from sennheiser with frequency 636.200MHz with ew100 G3.

The problem always occurred at specific locations around the stage. I still had the Canon R5C with me, which didn't cause any problems from the same spot.

Today was the most stressful job in recent years because I didnt get any control over that problem.

Thanks in advance and greetings from germany,
Jona

From spec pixis not send any signal.
Some question :

What do you mean crash? I had same mic and are radio mic, I had problems only near some high tension sources.
Problems mean noise, not crash.

Do you turn on off camera and see happen and disappear the problem?

Camera is wall power or battery or plate + battery?

What kind of audio setup there is?

Are you tested in other environments the same setup and see same problems?


Inviato dal mio iPhone utilizzando Tapatalk

Well first thing id be double checking.. Pretty sure 636.200MHz with ew100 G3 is B range and those frequencies are no longer LEGAL... especially in the US.. not sure where you are located but there could very well be a 2 way radio on those FREQs also....

carlomacchiavello wrote:From spec pixis not send any signal.

Well, no, there is a Bluetooth antenna in the Pyxis and intermodulation from those higher frequencies is a real concern. Plus, just because a system isn't explicitly transmitting doesn't mean that it isn't also generating some kind of EMI. Happens all the time.

With that said... This is still user error, IMO:

* Have you tried using different cables with your receiver?
* Did you try putting the receiver in another spot on the camera, or moving it farther away with a longer cable?
* Why didn't you try another frequency?
* The G3 series has a frequency scanner that tells you what channels are free of interference. Did you ever try using it while the Pyxis was on so that you could find a usable channel?

And like other folks have mentioned, anything above 600MHz is already very, very congested. That spectrum has been auctioned off for other uses.

Lost in translation? I believe the OP, who is in Germany, is stating that the Pyxis caused interference (clash) with the house wireless and PA. Most of 600-800mhz is no go in the US, abroad it’s likely a different tale.

https://apwpt.org/wp-content/uploads/20 ... 2021_1.pdf

Good Luck

Alex Mitchell wrote:

carlomacchiavello wrote:From spec pixis not send any signal.

Well, no, there is a Bluetooth antenna in the Pyxis and intermodulation from those higher frequencies is a real concern. Plus, just because a system isn't explicitly transmitting doesn't mean that it isn't also generating some kind of EMI. Happens all the time..

I wrote this be cause he wrote that bt is off, I asked about powering be cause I found that sometimes power plate or battery modules could produce some EMI.

We wait his answer

I’m following this thread because the theatre where I record (Canada) can use at least 16 wireless mics on the performers. I know in the past they have struggled to get all mics functioning clearly due to band issues complicated by the fact the theatre is close to an airport. I’d hate to buy a new camera and discover it screws the performers!

Thanks for all the replies y'all, really appreciate it!

First of all, I'm from Germany, and the event also took place here.

The problem the pyxis caused was an interference with the universities PA. We know, that it came from the pyxis, because I made the following test in an emoty room after the event ended:

When nobody was in the room, I walked past the speakers with the pyxis on and off (just with the body without lenses or other acccesoires). When it was on, there was a noticeable interference in the room, at the same spots (so it didnt happen random) . When it was off, there was no interference at all, no matter where I was.

Our pyxis is powered through a 98wh BPU Battery and at the test afterwards we left all the accessories in another room, so it was just the body with the battery.

We could not get to the receivers because there are locked in a secure room. So we could not change frequencys.
The frequency of the PA was as mentioned: 636.200MHz with ew100 G3.

I hope someone has a solution or an idea to solve the problem.

I won't be able to go to the event room again for testing because it's in another city. But maybe we can work together to find out what the problem might have been so that we can work in a more problem-oriented way if it occurs again in the future or if other people on the Internet have the same problem and can report it here.

Well, no, there is a Bluetooth antenna in the Pyxis and intermodulation from those higher frequencies is a real concern. Plus, just because a system isn't explicitly transmitting doesn't mean that it isn't also generating some kind of EMI. Happens all the time.

That sounds very interesting. I keep that in mind. A solution would be to change frequencys from receiver and transmitter?

Thanks in advance and thank you all for help
Jona

Perhaps the next time you go to that venue, you can prearrange a test where the wireless frequency for the PA system is changed and then you can see if that solves the issue.

BMD may comment on this as this sounds like a potential camera issue for the European region.

find an Audio guy around you with an RF explorer, or RF spectrum analyzer, and scan out the pyxis.

Thank you both!

RF-Explorer oder RF-Spektrumanalysato

I will do and report here!

Sennheiser have a free app which you can use with the EW series receivers. It's called WSM
https://www.sennheiser.com/en-ie/catalo ... wsm-111113

I'd be very surprised if the camera was causing issues, I use a bunch of Ursa Broadcasts and wireless comms and Teradek wireless transmitters and I've never had an issue. I'd definitely connect a laptop to the receiver and do a scan with the software to check

Hi Thomas,

thank you very much. I have blocked me a day beginning of january to analyse this problem in detail.
After that one time never had issues again at other events. I have everytime a blackmagic 6k pro as backup with me if problem is there again.

I will keep you updated!

TIA for trying to get to the bottom of this!