distorted signal when when charging??

amcutem · Post by **amcutem** » Thu Sep 29, 2011 5:08 am

Hello guys?

I was curious if anyone else is having the same problem as me?

When Im using my 4ch pico and my HP laptop is plugged in into the charger, my signals get really distorted, and when I unplug my laptops power supply/charger, then the signal get way better?? But I need or want my laptop plugged in so It doesn't die while im diagnosing?

What do you guys think? Please help..

Post by **Martyn** » Fri Sep 30, 2011 9:53 am

Some laptop power supplies do not have an earth connection and produce large amounts of interference. If you have problems when the laptop is run off it's mains adaptor, but not on battery, you can try earthing the laptop. There is often a screw on the back of the laptop that can be used for this purpose. Alternatively run a wire from the USB connector shell to mains earth.

hbr · Post by **hbr** » Sat Jan 07, 2012 6:38 pm

Hello, i have the same problem also with a hp laptop. Did you solve the problem? Or else how can i earth the laptop?

Avdr · Post by **Avdr** » Sun Jan 08, 2012 9:28 am

I have 3 HP chargers and 2 HP/compaq laptops.
1 charger is genuine HP, the other 2 are cheap chinese copy's, both of the cheap ones cause interferance, noticable when working close to a radio or TV, the HP one doesn't cause any interferance. I would recommend a genuine HP charger from personal experience.

Andy

hbr · Post by **hbr** » Thu Jan 12, 2012 6:07 pm

Hello my charger is an original hp.

Post by **Martyn** » Fri Jan 13, 2012 8:51 am

hbr,
Can you email support@picotech.com as we would like to investigate your issue in more detail.
Kind regards,

hbr · Post by **hbr** » Tue Jan 17, 2012 10:00 pm

Hello Martyn, i send a message to picosupport.

Dave Hill · Post by **Dave Hill** » Thu Feb 23, 2012 11:51 pm

I use several laptops in the workshop & some of them display interference when the charger is plugged in.

They are not all HP laptops either. I have two Toshiba units that I have to disconnect from the mains supply, if I need a "super clean" signal.

It isn't a major deal though.

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