TOPIC:

Hello,

I use an projector and a motorized screen for movies and TV. All other electric equipment is located at the opposite wall (~4m away).

1.
If the motor screen moves down- or upward, it's hand switch may produce some (electrical) noise through the mains wiring (not measured) due to switching sparks. Up to now there were no problem for all the other equipment.
But the nanoAVR resets every(!) time (including video and audio).
Yes, I will do something to suppress that noise. But the nanoAVR seems to have an EMC issue.

2.
During the search for the reset reason the DC connector of the SMPS came loose. This produced some crackling and the nanoAVR was down afterwards. No video, no audio, no Ethernet connection. The IR remote still functioned anyway interestingly.
Connecting the nanoAVR via USB, it could be brought back to life by reloading the configuration.
The Ethernet connection is still down (no connection to the PC-Software possible, nanoAVR is not marked active in the Routers config).
What can I do to reanimate the Ethernet connection (I'm an fairly experienced electronics HW engineer)?

Thank you!
Cheers, Timo

@Timo

1. Not sure where the EMC comes into play here but did you investigate if it's not something grounded related? It sounds like something in your install is setting some strong ESD potentially... Maybe start step by step to eliminate connections to see what that spark sets off (i..e input/output/or DC related.. fixing the spark on the AC might be a good start though as safety wise that doesn't sound too good to us..

2. mmh, this is odd.. we've never seen any of the like on all the nanoAVR we shipped... (i.e. DC connector coming out??) best to start a tech support ticks so we can see what's going on here..
As for the USB/Ether, please note the following: You can't have Ethernet and USB cable connected together. Asap you put a USB cable into the unit, it will disable the ethernet. That's how the device operates for the firmware to have on overide.

Devteam

Hi,
thank you!
I will communicate this issue via the support.
Cheers, Timo

Hello devteam,
because I still got no answer on my support requirement I put it here.
==============================
Hello Devteam
and thank you for the answer.

1. I put 2 different spark blocking circuits into the switch:
- 47 Ohm+100nF across the up/stop/down switch (2 pieces)
- 20mm 650V MOVs (measured with a Keithley 2400 SMU for 1mA) across the motor wires to N (2 pieces) and alternatively across the switch
Unfortunateley the switch is in the mains cable's middle, creating a long antenna between the screen and the switch.
The "reset" problem remains. But you're right, it's not necessarily a nanoAVR reset. The nanoAVR's LEDs do not show any change. The projector shows a bluescreen for some seconds at least and some internal relay switching. During that time the audio is off.

- Disconnecting all cinch inputs: no change
- Switch off the projector (cooldown time): no change
- Full Switch off of the projector (after cooldown): no "reset"
- Disconnecting projector at the HDMI's other end: no "reset"
- Disconnecting nanoAVR HDMI out: no "reset"
- experimentally putting a very good 2 stage RF/AF-Filter inline to the screen mains fits the "reset problem"

So it seems to me, that the projector communicates over HDMI (or there are glitches, still in the cooldown time) and this affects the "reset". The HDMI cable is in parallel with the mains cable for ~4m.
It's possible that inserting the nanoAVR HDA between the Octava HDMI switch and the projector makes the HDMI path more susceptible (possibly due to different HDMI functionality of the Octava in comparison to the nanoAVR).
Interestingly this behaviour is not seen at the end stops of the screen, although there must be (internal) stop switches.I will try a mains filter betweet the mains outlet and the screen next time.

2. The DC connector became loose/went out during fiddling with the very tight Neutrik cinch connectors. I did not see the loose connector until the crackling sound in the speakers happened. So the DC supply may(will) have created transients on the DC input rail.
The connection via Ethernet is still not possible, neither over the router nor via direct connection to the PC (with different IP addresses of course). The router remembers the nanoAVR's IP address but does not see it activated (it means, it is disconnected). See the attached pictures.
Also "ipconfig" does not show the nanoAVR's LAN connection.
Putting the USB cable in or out does not change the behaviour. Without a connected device at the other end this seems to be correct.

I tried and measured different USB power supplies (apple iphone 12W, apple 5W and an unknown brand) with and without a connected USB cable. Apart from the more stable voltage of the nanoAVR's supply with ~ 1A load, the noise of your supply is lower (measured using a Keysight MSOS404A).
Additionally the usual USB-cables are not capable to deliver high power to the load due to high cable resistances (measured too, one 2m cable showed a 1.5V drop at 1A!).
On the other hand it would be very nice, if the PS would fit into a narrow Euro-slot of the mains like a 5W apple iphone supply.

So, the nanoAVR HDA seems to be defect in case of its LAN connectivity. I'd like to use this LAN-config possibility as stated in the nanoAVR's description. What can we do to solve this issue?

Thank you!
Best regards, Timo

> Customer: Timo Kirschke
> Subject: nanoAVR HDA EMC issue?
> Tech support team | JUN 06, 2018 | 10:48AM HKT
> Hi Timo:

> 1. This sounds weird as we hadn't heard of this before, the nanoAVR has passed EMC test and should be working fine in most circumstance. Normally, if the nanoAVR reset, you should see all LED light up and then change to only preset and source LED light up, did you see this pattern when it reset? Had you try to use another 5V power supply, can it help?

> 2. Had you tried to connect nanoAVR directly to PC via Ethernet? Please set PC to obtain IP by DHCP, the nanoAVR and PC will talk to each other and will automatically get IP address by themselves. Then you can try to connect using the nanoAVR plugin software. Did the LED on Ethernet port light up or blink?

> Best Regards
> DevTeam

Hello,
Ethernet problem fixed.
Using a new PC with Win10, the nanoAVR HDA connected to it via Ethernet using a different IP address.
It is still necessary to disconnect the USB cable between the PC and the nanoAVR when using the Ethernet connection.

Additional question:
The volume control seems to increment or decrement the volume level in 3dB-steps, when using the Logitech Harmony (Companion).
Is that an issue of the remote control (maybe, the RC-signal lasts to long) or of the nanoAVR software?
If so, is there a way to lower the steps to 1dB?

Thank you!
Best regards,
Timo

Hello,
volume control problem fixed.
It was related to the Harmony. Shortening the command sending duration lowers the repetition number of the command sended by the Companion Hub to the PC (here to once).
So the single volume up-/down steps are 0.5dB now.