fuckin evil
mfkr just crossed the streams
Posted by renesis at 19:44 | permalink | 0 comments
lordpil's blog
well you saved enough money you can buy a nice low Vos low drift rrio opamp
and use it to do gain and filtering
Posted by renesis at 12:17 | permalink | 0 comments
wow 5.5 to 6.5mV
looks accurate
timecop: so yeah the old sensor is about twice as sensitive
so yeah everything is working perfectly
thats just the maximum range timecop
not the voltage it outputs at max range
so the old one is capable of twice the swing
opamp or new sensor
cmon you knew this one
why did you pic the new one?
cheaper?
well now you know part of the reasonw hy
Posted by renesis at 12:11 | permalink | 0 comments
along with a load to get some current on the trace so maybe it doesnt get so much noise
but that wont help your problem
i would see how it response without any filters
no i think it just might be lower sensitivity, the sensor
full scale?
whats full scale
.83mV per degrees per second
the 4x channel is 3.33mV per degrees per second
so whats the other one say
the old sensor
maybe they dont have the same output range
ha
Posted by renesis at 12:03 | permalink | 0 comments
so its spiker, bit noisier, and you still dont get the gain, right?
maybe another 50mV if that
the sensor just isnt as sensitive
how do you have it loaded?
it shouldnt matter much, but try putting like 10K from the sensor output to ground
right
for production shit i would prob load it up with like 10K at the adc pins, with an RC right after that
tuned close to but not the same as the RC between the sensor output and the 4x amp
right thats what im saying you should do
Posted by renesis at 11:58 | permalink | 0 comments
its appropriate
reduce the 47k to 10k see if it makes a huge diff
it prob makes shit a tad spikier but i dont think its going to make the new sensor hit the same amplitude as the old one
yeah try that
should be noticable if it matters
just solder a 10k on top prob makes it like 8k
that shit has internal filtering too
rab: hi
Posted by renesis at 11:53 | permalink | 0 comments
it looks reversed
and less sensitive
opamp and amplify or deal with less resolution on your rotational values
it might
but probably not
47e3 * .1e-6 = 0.0047
thats about how long it takes for your rc to hit 3/4 of your full input voltage
ya
so it should smooth it out but it shouldnt attenuate the fuck out of it, judging by the 400ms divs on your images
Posted by renesis at 11:48 | permalink | 0 comments
weird @ high pass shit
and it could be killing response time
the lpf could be killing response time but eventually it should be a correct value
it depends on the RC values used
yes thats what it does
reduce the values
sure
tho thats prob not the problem that doesnt seem like too strong of a filter for that kind of response time
sup
what 2nd pic
Posted by renesis at 11:43 | permalink | 0 comments
you just have shit res to begin with
if you dont scale
no idea what youre doing with the sensor or how much you need tho
Posted by renesis at 11:36 | permalink | 0 comments
or .2v or however the lowest signal of the sensor is
you can prob do this with a RRIO amp
rail to rail input and output
use a 5.5v source instead of ground
depends
Posted by renesis at 11:18 | permalink | 0 comments
prob not in alaska
timecop is azn
cheater is saying what i said earlier
he just didnt say opamp
and you need more headroom multiplying first fuck that
you just need one stage
eh?
i would have the vin- at like 1v
Posted by renesis at 11:13 | permalink | 0 comments
so i mean basically your resolution is destroyed because youre amplifying noise and using a small part of the adc
so you have a solution
does this need to be cheap?
you need an opamp with badass input voltage offset specs
and then you need to shift the signal down like 1V
and do a gain of like 6
assuming 450mV max
and you filter as much as possible
if you can deal with a bit of latency, filter at like 1Hz
even 60/120Hz hum will be mostly gone
Posted by renesis at 10:59 | permalink | 0 comments
anyway make the signal full range, filter out noise the best you can without fucking your measurement latency
or deal with degraded resolution
well then youre clipping
if youre up to 1.8v and its 4x
so youre saying its 450mV
max
between like 275mV and 450mV
youre prob going to have like 10mV of noise without any filtering
amplifier to 40mV internally
*amplified
Posted by renesis at 10:54 | permalink | 0 comments
shit im almost done with fakemeat bacon cheeseburger and i cant find onions
eh
for the adc to use a narrower range you mean?
and you can use an external vref
to limit to 1.8
i dont think you can raise the lower limit, unless you have a diff adc and youre using another vref on the - input
no in software you have to deal with shitty resolution
or you do it the smart way
use opamps to shift the level down 1.8v, with a gain of around 4.2, and use the full scale 3v vref
oh my bad shift it down 1.1v
Posted by renesis at 10:49 | permalink | 0 comments
i think you divide by 1024 not 1023
like if you have a 1.024V ref, 0 doesnt really mean 0mV it means 0mV - 1mV
yeah so do i but for a second i thought maybe im fucking it up
Posted by renesis at 10:27 | permalink | 0 comments
oh i guess silica gel isnt really poisonous its stuff they add to it
and yeah fuck silica beads in the herb
gotta have rules
Posted by renesis at 08:42 | permalink | 0 comments
for cats?
and silica will still get stuck in their paws and get all over the house
the big pine pellets are the only thing that didnt do that
Posted by renesis at 08:35 | permalink | 0 comments
no idea what mine is made out of
no
im thinking about buying the pin pellet stuff again
pine
necr0s: neat
except i dont have a back yard
i guess it could poo in the courtyard, but there are dogs
Posted by renesis at 08:25 | permalink | 0 comments
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