Logitech Cordless Keyboard question

JimG · January 9th, 2002, 11:23 PM

Interesting situation I ran into tonight. Had my sister's computer about a foot from mine tonight, because I was installing her new network card (my Dad thought ethernet card = modem .. do the math). So I was testing it ... used a crossover to connect to my PC. So I go to browse from my PC to hers, and all of a sudden I can't type. Typing gets real sluggish ... takes 15 seconds for a character to appear, and sometimes it doesn't appear at all. Figured the batteries were toast .. so I replace them. No change. So I start thinking, ok .. only other thing I did was to put my sister's computer under my desk. So I turned it off. BAM! Typing is back to normal. So what the heck caused her PC to interfere with my keyboard? The receiver is behind my PC, and works off RF, so it doesn't need line of sight. Anyone out there got any ideas?
Her sys is an AMD 850, Abit KT7 and 300 W PS. Mine's P3 800, Abit BE6 and 300 W PS.

OC Guy · January 9th, 2002, 11:29 PM

I have a logitech wireless keyboard and there are only two things that might have contributed to your problem. First some computers have emi sheilds, your sister's computer could have been blocking your signal. Last, if your connecting to someone's computer, your computer could become slow and unresponsive. I know about the whole slow part, even when im on my 100mb, full duplex home network, things can get slow at times. This was just my .04 cents, 2 for each guess.

ps- i love my wireless keyboard!!!

JimG · January 9th, 2002, 11:46 PM

Interesting, didn't think about the EMI shield. Maybe too much metal under the desk just overwhelmed the signal. As for the network connection, I can easily test this idea by unplugging the cable and booting her PC. Will get back to you tomorrow on the network connection.
And yes, wireless keyboards rule. No cord to get in the way, and moving from dorm to dorm they're really nice because they adapt to new desk styles so well. And you really can't beat sitting 6 feet away and typing.

cadetstimp · January 9th, 2002, 11:49 PM

If the reciever was sitting on the desk just above her power supply under the desk then there could have been interference. Most interference from a PC comes from its power supply.

Tomteriffic · January 9th, 2002, 11:53 PM

Just a guess, but I'd second the EMI idea, what with two power supplies as well as a couple of processors operating at two different RF kinda freqquencies.

To take the guess a bit further, a lot of that RF keyboard/mouse stuff operates on the 49 Mhz band, which is very close to the difference in clock frequencies of the two CPU's. Maybe the intermodulation byproduct of 50 Mhz , with both machines in close proximity did it?

JimG · January 10th, 2002, 12:05 AM

cadetstimp,
Actually, the receiver for that and the cordless trackball (I got this cordless theme going here) are sitting behind my computer on the floor. Got a little lazy and didn't mount them to my desk, since it all moves out Monday AM for another semester in college. I'm now thinking based on what you, OC Guy, and Tomterrific said that the interference was caused by the EMI and all the gear under my desk.
Tom,
Umm, what can I say but wow. Didn't know what freq the RF stuff operated at, and I never would have made the connection to the differences in clock frequency. The two PCs are a little over a foot apart, say 14-15 inches. That's some really cool thinking there.
Thanks for your help guys.