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heh @ robofish

Posted by renesis at 23:22 | permalink | 0 comments


same thing
is it a big one?
hmm, i think are hp at school was even bigger

Posted by renesis at 13:19 | permalink | 0 comments


neat i think new emc fixed the oscillating stepgen bullshit

Posted by renesis at 13:08 | permalink | 0 comments


haha
its a funny idea
your cable is like an inductor with caps to ground
so if your noise is so bad its liftiing grounds in the scope, then its prob bad enough to create diff noise on diff sides of your cable
faraday cage
.
indeed

Posted by renesis at 12:27 | permalink | 0 comments


oooh
yeah thats the only way ive gotten shit from there

Posted by renesis at 11:03 | permalink | 0 comments


heh you paid
damn so 3rd party search just crawls thru all of rapidshare?

Posted by renesis at 10:58 | permalink | 0 comments


haha youre still having problems?
we dont have ants or roaches here
just crickets
haha nice

Posted by renesis at 10:53 | permalink | 0 comments


maybe has a roll mode and 10sec divs or something
wouldnt matter in roll mode!

Posted by renesis at 01:23 | permalink | 0 comments


it has defeated your scopes grounding
NEEDS MORE ENGINEERING
its japan i dont see this as being unlikely at all
timecop: proceed with random RFI testing
first task: rotate scopes randomly and see if it changes
also walk around scope to absorb cancer causing waves, check results again

Posted by renesis at 01:17 | permalink | 0 comments


that funny i didnt think of saying that but in the same situation i prob be flippin the big virtual paddle every 10sec
timecop: unhook your probes and try
ha sucks
its autoranging right now?
see if its 20mv with diff voltage divs
this thing maybe has bad internal grounding
what
this is that $20K scope you were babbling about?
this isnt china shit?
if its doing it on both youre prob just living in an EMI storm
and the scopes pcb grounding is maybe fail

Posted by renesis at 00:51 | permalink | 0 comments


filter set to 20MHz?
same thing
if its exactly 1/2 the voltage, my guess is your noise source is like ~40MHz
do a single scan in sampling mode and look for patterns
or try taking it to another toom by itself, or diff outlet, see if it does same shit
w34s3l: its probably counter output from the noise

Posted by renesis at 00:42 | permalink | 0 comments


dunno, single sweep it and see if there is a regular signal on it
also try a .1uF right at the chip if you dont already have one
also maybe 100pF
what
you have 3.3V offset when you ground your leads?
(if yeah youre going something wrong)
oh the noise
yeah dunno, its maybe just noisy around you
yup
look for filtering/bandwidth limiting in the scope settings

Posted by renesis at 00:36 | permalink | 0 comments


timecop: i dont mean the readout i mean the actual wave
it does that with the LDO?
doesnt look like ripple unless youre triggering is totally fucked
looks like noise

Posted by renesis at 00:31 | permalink | 0 comments


is your scope ground earthed?
or isolated
is maybe a little bus bar in back
yeah but sometimes they have a little bars between some terminals
so you can unhook it and float the scope
short of that, tethering to the DUT with your probe ground should kill the ground floating
i had to check other shit!
unhook it
clip probe ground onto probe tip
and see what it says
yeah you got problems or there is some sort of offset for the measures
can you see this?
the 3.3v rail and the ripple

Posted by renesis at 00:26 | permalink | 0 comments


if your probe is floating itll pick up noise
480mv ripple after the LDO?
at what freq
check the input to see if youre dropping it out
haha you think?
not enough cap before the LDO might be it
connected to the LDO
or your probes
dude floating probes dont mean anything
whats the board grounded to
so wtf isnt connected
haha is your psu actually grounded?
or its some DC wart
heh
maybe this is why it was $900 instead of $20k?

Posted by renesis at 00:21 | permalink | 0 comments


hi
you have a scope why are you measuring ripple with a soundcard

Posted by renesis at 00:00 | permalink | 0 comments


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