buzz/hum from Lilliput? higher pitch with higher RPMs...

chris in nh · 07-04-2004, 12:50 PM

for testing purposes i am running my laptop off it's battery. i have the Lilliput plugged into the cigarette lighter. the Lilliput is connected to the lappy via the VGA cable. the headphone out of the lappy is connected to the AUX IN (rca) of my car stereo. i get audible humming which gets a higher pitch as i rev higher. but when i unplug the Lilliput and just listen to an mp3, i don't hear the humming...

eventually i'd like to power my whole setup from an Opus. i have an email in to them right now to see if i can do it. haven't heard back yet. i don't know if this will solve my problem or not, but the other Opus features would be useful regardless.

i read the 'ground loop' thread below. looks good. just wondering if anyone has any thoughts about possible (easy) fixes...

thanks!

Pudge · 07-04-2004, 12:57 PM

The egg is a noisy POS.

zijester · 07-04-2004, 01:02 PM

Its not the egg its the car cig lighter . Get a fuse tap and wire it to the fuse box. I use the radio fuse. That should help.

chris in nh · 07-05-2004, 11:22 AM

ok, both answers are a good start.

what if i could hook the Lilliput to an Opus? do you think that would take care of it?

binary.h4x · 07-05-2004, 11:29 AM

try adding a couple capacitors in parallel to the power lines going into the lilliput.

chris in nh · 07-05-2004, 11:41 AM

flux capacitors?

just kidding. i have no idea how to do that, much less what a capacitor is!

can you point me to one, or an install procedure, etc? and when you say 'power lines' which lines are you talking about? (Opus that i plan to install, cig lighter, etc.)

thanks!

Litespeed · 07-06-2004, 10:25 AM

Run it off the 12V rail on your Opus. Problem solved.

WhiteRabbit · 07-07-2004, 02:07 AM

if you get noise when plugging in the lilliput, thats where your ground loop is. you can reground that, it shoudl help.

next thing, for $20 you can get a ground loop isolator form a stereo shop, it can help sometimes, you can experiment putting it in different places along the signal line, the closer ot the nosie source, the more effective it shoudl be

chris in nh · 07-09-2004, 11:55 PM

i got an email back from the Opus folks. the Opus unfortunately will not work with my laptop...

so how would i ground/re-ground the cig lighter? sorry, i am completely stupid when it comes to this...

chris in nh · 07-25-2004, 03:19 AM

*bump*

i KNOW you guys know the answer!

problem is (alternator/engine) noise on the line. noise seems to be coming from the Lilliput. grounding was suggested, but i'm not sure how...

the Lilliput is currently plugged into the cigarette lighter socket, but i found a source of 12V power (switched and unswtiched) under the center console. it's in case you want to power your phone or other overpriced option. so, assuming i want to use that line, how would i begin to ground such a connection? or can i just ground the Lilliput somehow?

system is Compaq Presario 1688 laptop (K6 - 400MHz, 128MB RAM, XP Pro) - soundcard connects to Becker CDR-220 HU, video connects to Lilliput 7" touchscreen.

thanks!!!

Motoko · 07-25-2004, 06:23 AM

power lili of a 12v line from the Opus.

chris in nh · 07-25-2004, 11:10 PM

Quote: Originally Posted by Motoko

power lili of a 12v line from the Opus.

i don't have an opus. it won't work with my laptop. now what?

Grayscale · 07-25-2004, 11:15 PM

yeah he just said that

i would try grounding your lilliputs negative power wire...or ground to the chassis of your laptop or negative power wire going into it (if you start running it without the battery) just run a wire between the two negative power wires...

chris in nh · 07-25-2004, 11:25 PM

Quote: Originally Posted by Grayscale

yeah he just said that

i would try grounding your lilliputs negative power wire...or ground to the chassis of your laptop or negative power wire going into it (if you start running it without the battery) just run a wire between the two negative power wires...

awesome! how?