What is the strangest behavior you have witnessed in a system?

While finishing a service call on an AV / Control system, I was testing a 1500 wireless crestron touchpanel for consistency. As I pressed the lights buttons, I noticed the programmer's laptop beeping every time I pressed a button.

I looked at the computer, and I saw that every time I pressed a light dim button, his laptop's screen brightness decreased by half, and brighted again with a lights up button press!!!!

Computer is an IBM Thinkpad, crestron is controlling a Lutron radio ra interface.

I thought maybe something was being received back through the serial cable, so we removed the cable from the crestron processor, took out the laptop's wireless lan card, and disabled the irda port (overkill, but this was pretty wierd).

The laptop still responded every time to the button presses. I still can't figure out exactly what it was receiving and why, but it was pretty cool to see that the IBM thinkpad has discreet brightness control!
And 3 technicians saw it!!

Was the power cord plugged in?

Mike might be right, if the laptop is in a plug affected by lights up/down (don't know anything about Lutron radio ra) then when the power is dropped it might not have the juice needed and the laptop switches to battery mode and then when you click up it might be going back into power mode

I am using an IBM Stinkpad right now, and if I unplug the charger, the screen does not change brightness at all. I just looked at settings and cannot find a way there to change the screen brightness. For that matter, there is a control below the screen that changes its brightness (contrast, really) from 100% down to about 80%. Pretty ineffective, but definitely not what you are seeing!

weird... my Toshiba screen shows a dramatic difference when unplugged. I guess i got a pretty crappy battery.
Mike

The scree dropping brightness when on battery power is a feature. it increases the length of your battery time. This feature can be turned on and off. My compaq does this as well. Most of the time I like it but if you are in a room with alot of sunlight it is hard to see. Then I have to turn off the battery saving feature.

Robbie S

About a week ago I was installng a DirecTV system.

Cusotmer had a Daewoo TV/VCR combo in his bedroom. Everytime I would move i front of the doorway the volume bar on the bottom of the screen would pop up on the screen, when I would move back the MUTE signal would show up on the screen.

I plugged the receiver in and blew a breaker. tried it again (maybe plugger error) blew it again. I ran an extension cord out of the bedroom plugged it into the living room everything worked fine.

I told the customer that he might want to cal the landlord and have the electrical in the house checked out.

The I proceeded to run out the door before I got trapped in a burning inferno.

I dont remember if the laptop was plugged in to ac, but I don't think voltage drop was the cause. When I hit the lights dim button, I saw the green brightness overlay on the laptop screen appear and decrease, and increase with lights up. I don't think that happens when the IBM's power save comes on, but I'll check.

The light switch wasn't controlling a switched outlet that the laptop was plugged into was it?

what a novel idea rhm9 :-)

genius!

Customer had a Daewoo TV/VCR combo in his bedroom.


I think your answer is right there.