Electromagnetic Interference from Wifi on PM3

[hmayes]

Has anyone had any problems with possible electromagnetic interference from a home network wifi?
We had a rowing party at our home to see if we could add some meters to our January Virtual Competition total. We had two model D's and set up a laptop that was connected to our home wireless router via wifi. Both PM3s started acting strangely, freezing up or zeroing out from 17 meters to around 240 meters.
We think we narrowed it down to the wifi as we shut down both the laptop and the wireless network and then replugged the batteries. Everything worked after that.
I apologize if this has been discussed before, but looking through the topics, I did not see anything listed.
Thanks,
Howard

[Slothful1]

Hi

I've always connected my PM3 to RowPro running on my laptop, which has a wireless connection to the router, and haven't noticed the problem you're experiencing.

Were the PM3s exposed to the cold while being transported? There might be problems with the performance of the batteries at extreme temperatures which then warmed up at the same time as you shut down the laptop.

Maybe drop c2scott an e-mail (his address is in his avatar) or hopefully Citroen will be along to help shortly.

What software were you running on the laptop - the C2 venue racing software or the new RowPro v2.2 beta? Maybe connecting 2 PM3s directly to the laptop without using a powered USB hub could have caused the problems you're seeing?

Cheers
Dave

[Citroen]

I've heard of static problems with wired ergs, but nothing with WiFi causing problems.

The USB cable is 5m (max allowed length) so that's as far away as you can get the ergo from the computer.

Check that the HR monitor and sensor cables are intact. Check that the flywheel sensor is correctly mounted.

Change the WiFi to another channel. Connect the computer to your router with a cat-5 cable rather than wireless (which isn't ideal, of course).

I've never used an ergo online, but plenty of other folks are doing that with RowPro for online racing.

I won't suggest wearing a tin-foil hat.

[hmayes]

Maybe some more information can answer some of your questions about the incident.
1. One Model D was purchased in January of 2005, the other in December 2006.
2. Both PM3s had firmware versions of 97. The older PM3 had a hardware version of 431, the newer one, 450.
3. The older PM3 had a heart rate monitor receiver connected to it, the newer one did not.
4. The newer Model D was transferred by car, for 2 hours, in cool weather, 35 degrees F, but was brought down to the basement, which was at 69 degrees F and was down there for approximately 5 hours before we rowed.
5. The laptop was not being used by the ergs but was there so people could see the standings. The wireless transceiver was a D-Link USB dongle that was approximately 6 feet from the one erg and 9 feet from the other. The wireless router, also a D-Link, was approximately 30 feet from the ergs, on the upper level of the house. Although the router has a Super-G link capability, that was turned off.
I appreciate your comments.
Thanks,
Howard

[Slothful1]

Thanks for the extra info, but I can't offer much more on this. Presumably the second erg has relocated, but I might try reproducing the problem with the single erg. Leave the laptop running but disable the wi-fi link. There might just be some serious interference coming from the laptop itself.

I always use a Polar heart rate monitor with the PM3 and wi-fi connection, so I should have enough interference going around near my C2. My router is also about 30 feet away, but through 3 brick walls, so I generally keep my laptop wi-fi on max strength all the time.

C2scott is the right man to get in touch with now. He may have seen this issue during the development of the PM3s / 4s.

His profile is here...

http://www.c2forum.com/profile.php?mode ... file&u=342

I don't think he checks the forum that often, or his PMs, so best to drop him an e-mail.

Good luck! Please post if you find the cause of the problem.

Cheers
Dave

[hmayes]

I ran 4 variations of the test tonight to see if I could get the PM3 to act up.
All 4 tests were negative.
1. tried just the wifi router on.
2. tried the wifi router on and the laptop on but no web page up.
3. tried the wifi router on and laptop on with web pages.
4. tried the wifi router on and laptop on with web pages and with the laptop right next to the rower.

Differences from last Friday.
Only the older rower was in the room.
Only one cell phone was in the room.
Fewer display changes.

I am a little disappointed that I am unable to duplicate the problem but I am pleased that I am able to use the wireless network and computer with the indoor rower.

Thank you all for your comments and suggestions.
Howard

[fatboyrc]

I just got a similar problem with a 2x 30' i do on a Model C with a PM3 monitor.

On piece 1 i saw it hang for a little bit at around the 20' mark.

On piece 2 I saw it start at about ~23' to go it would hang the meters and after about a minute would let me go again and then a little bit later it did it again. Thinking that the TV may be the interferer i turned it off b/c the remote is close by. the laptop was on 3' from the monitor. I was wondering if it wasn't my new Cell Phone which I will place back in my other room and turn off the Wi-fi.

The nice part was that this was the first time It had save my HR data for both pieces and Piece 2 was 9 beats higher according to the monitor. 140 on piece1 and p49 on piece two which makes me think I lost ~500m on the pieces.

Hardware Version: 461. I bought the PM3 about 3 weeks ago. so I'll try to clean the airwaves from any extraneous noise via wifi and cell.

[michaelb]

I am still confused about what you were doing. What were you running on the laptop if it wasn't connected to the ergs? Why were the ergs plugged into a wireless hub via USB? Maybe they weren't now that I read your posts again.

1) you had two c2's in the same room;
2) you had a laptop in the same room and were using that to connect to the internet to see a webpage, presumably, the Jan Challenge?

I really have a hard time believing that the laptop or the wireless signal had anything to do with your problems, but maybe it could and someone from C2 will have some help.

For what it is worth, my rowing computer on which I always run rowpro connects wireless to the internet using wifi and I have been doing this for years with no such problem. Lots of other people use rowpro and connect wirelessly.