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arch2b
2006.07.15, 12:27 PM
core,
can you tell us what frequency range core operates on? i seem to get horrible interference from a wireless connection in the room just above the one i'm running core in. i also have to disable everything 'wireless' on my laptop as well.

oddly enough our only cordless phone has never caused problems.

rkk
2006.07.15, 01:38 PM
RFID systems general fall into 2 categories, low frequency (125 KHz for example) and high frequency (13.56 MHz). I originally thought the core system ran on 13.56 MHz because of the tag size. So I started looking to see if I could isolate what might be causing the interference. Fluorescent lights run in the sub GHz frequency range so they can be rules out as they wouldn't interfere with you laptop. The wireless card on your laptop (802.11x) is 2.4 GHz. Microwave ovens are also 2.4 GHz. Cordless phone are generally 2.4 or 5.8 GHz, although older models are on 900 MHz. Looking further I found that there is quite a bit of buzz about 915MHz RFID (13.56 was all the rage when I looked into designing my RDIF timing system).I also discovered the most common problem with 13.56 systems is that being mounted on or near metal introduces substantial interference.

• Your cordless phone doesn’t cause interference: chances are you phone is newer than a 900MHz model so there is a possibility the tags are on 915MHz
• Your laptop had problems with its wireless card (2.4GHz). This is the most common cordless phone frequency and there are always microwave ovens to consider.
• If the mini-z’s have a lot of aluminum upgrades that could be a problem, and the laptop is an unfortunate coincidence.

Sorry for the dissertation, was just trying to work it out in my head. My bet is the core system ,judging by tag size, is 13.56 MHz

kevo1036
2006.07.15, 07:02 PM
This might be a little different but I just got my core and tried it inside and it was getting like 97-98% signal strength, but when I took it to the RCP track in my garage it was getting like 60-65%. I still didn't miss a lap but I was wondering if anyone has had similar problems. I have it on top of a cardboard and under the RCP track. If it isn't in a perfect triangle does that make a difference much at all?

kevo1036
2006.07.16, 01:58 AM
I moved my computer farther away and that seemed to help or maybe something else was going on during the day but that is my best bet?

arch2b
2006.07.16, 12:32 PM
the loop under the track should be exactly as pictured in the manual. atleast 12" inches apart in a enlongated loop, not a triangle.

kevo1036
2006.07.16, 10:07 PM
I did have it in a loop and it was acting up during the day. Said strength was around 60% but never dropped a lap. And I ran it later at night and moved the computer a little farther away (I was using a desktop), and it worked fine (around 95-98%). So I guess it's not a big problem just wondering if anyone had the same problems.

arch2b
2006.07.16, 11:10 PM
yes, i have desktops on either side of my hfay laptop and i have to turn the one with the crt monitor off inorder for core to work. if i leave it on, it will only count the 1st lap and then nothing else. as soon as i turn that pc off, it works fine. keep the usb cable as far away from other devices as possible.

can you buy a sheilded usb cable? i know they make sheilded network cable

kevo1036
2006.07.17, 11:35 AM
can you buy a sheilded usb cable? i know they make sheilded network cable

I'm not sure. I haven't had any problems to the point of where I have dropped laps. I had problems with a friends laptop but it was running real slow but I haven't dropped a lap yet with my desktop.

mini-z
2006.07.17, 08:33 PM
We had a bizarre issue this past GTG where the Core system wouldn't work at all - we tried all kinds of different things, moving it around, turning other devices off etc. - in the end, it started working when we unplugged the laptop power cord! As soon as we plugged it back in, it stopped working again - unplug it and it's fine again. We never had this issue before, it was bizarre. Same location, same laptop, same everything except specific track layout...?!

briankstan
2006.07.18, 12:33 AM
I haven't had any issues with mine since I reloaded my laptop with only the new update. Hasn't missed a lap and starts everytime.

I would guess it's an enviromental issue. maybe something in the ground that can't be seen.

Hope your issues get resolved.

That is just weird on it working with the laptop not plugged in and then not working when it is.