#garfield Logs

Mar 02 2020

12:49 AM polprog: morning rue
12:55 AM polprog: rue_mohr: where is that chart from?
12:55 AM rue_mohr: he's right, its a neuron impulse
12:55 AM rue_mohr: and I cant find a REAL capture of it with the simulus overlaid
12:55 AM rue_mohr: EVERYONE just draws it
12:55 AM rue_mohr: and they all have a different creativity in their hand
12:59 AM polprog: hah
01:00 AM rue_mohr: I just deleted all the bio terminology
01:00 AM rue_mohr: its still some kinda simple discharge circuit
01:00 AM polprog: are you going to build a fet driver for the neurons now?
01:00 AM rue_mohr: its just a digital pulse
01:00 AM rue_mohr: nerves are pfm
01:00 AM polprog: pfm?
01:01 AM rue_mohr: pulse freq modulation
01:01 AM polprog: pulse freq modulation?
01:01 AM polprog: ah
01:01 AM rue_mohr: wow, we both shortened frequency
01:01 AM rue_mohr: hahahah
01:01 AM rue_mohr: anyhow, yea
01:01 AM rue_mohr: there was an article a few years ago about how amazing pfm is for its dynamic range
01:02 AM rue_mohr: that said, nerves are digital
01:02 AM rue_mohr: and I work well with digital circuits
01:02 AM rue_mohr: so I need to work out a level translation circuit
01:02 AM rue_mohr: and those are slow pulses, were talking 1ms!
01:03 AM polprog: i see, replace your body with some fet drivers and lut fpgas :p live forever!
01:03 AM polprog: I wonder what is the amplitude...
01:03 AM polprog: 100mV, ok
01:03 AM rue_mohr: not forever, just 8k-10k
01:04 AM polprog: hmm.. not enough for HCT series
01:04 AM rue_mohr: the pulses usually sit reverse pol by about -70mv
01:04 AM rue_mohr: they spike to about +30mv, but anything over 0mv is a pulse
01:05 AM rue_mohr: and the pulse is all that matters, the duration of it doesn't
01:05 AM rue_mohr: the pulse *is* the event
01:06 AM polprog: Interesting what keeps it at -70mV
01:07 AM rue_mohr: yea, there must be a pretty good little isulator around a nerve eh?
01:07 AM rue_mohr: but the answer is something like 'salt and potassium"
01:07 AM polprog: hmm
01:07 AM rue_mohr: whatever, I dont care
01:08 AM rue_mohr: I'd like to thunk up a circuit that behaves like that
01:08 AM polprog: i wonder whats the propagation delay.. can i make a neuron ring oscillator? :p
01:08 AM rue_mohr: they can oscillate on their own
01:08 AM rue_mohr: 1 sec
01:08 AM polprog: like that as in makes these pulses or has several inputs and one output like a neuron?
01:10 AM rue_mohr: http://ruemohr.org/~ircjunk/tempimage/F1large.jpg
01:10 AM rue_mohr: oh, I never noticed that
01:10 AM rue_mohr: mv and pA
01:10 AM rue_mohr: so...
01:10 AM rue_mohr: zippo:/files/doc/human# ohm -v 30m -i 300p
01:10 AM rue_mohr: Power is: 9.000pW
01:10 AM rue_mohr: Current is: 300.000pA
01:10 AM rue_mohr: Voltage is: 30.000mV
01:10 AM rue_mohr: Resistance is: 100.000MOhms
01:11 AM polprog: hmm..
01:11 AM rue_mohr: I wonder if they just used a 100M probe?
01:11 AM rue_mohr: plausable
01:11 AM polprog: maybe.. seems to round of a figure
01:12 AM rue_mohr: anyhow, my point was, nerves can take on different stimulus behaviours
01:12 AM rue_mohr: BUT look at the firing rates
01:12 AM rue_mohr: not fast ~50Hz
01:13 AM polprog: yeah
01:14 AM rue_mohr: that fast one there, +- the reality of the data is only 30Hz
01:15 AM rue_mohr: seems to me that its quite easy to *electrically* interface with
01:16 AM rue_mohr: mechanically is a mess
09:24 AM rue_mohr: hmmm
10:25 AM polprog: ive got some chemical tinning solution
10:25 AM polprog: ill have to try it out on the next run
12:54 PM Tom_L: that stuff is nasty... be careful with it
01:20 PM polprog: thanks for the warning
01:21 PM polprog: ill have to use latex gloves instead of polyurethane coated paintinggloves
01:23 PM Tom_L: fumes too
01:25 PM polprog: hmm..
01:27 PM Tom_L: https://www.msdsdigital.com/liquid-tin-msds
01:27 PM polprog: says it contains tin (ii) chloride
01:27 PM polprog: getting a 404 there
01:28 PM Tom_L: https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&uact=8&ved=2ahUKEwikhZf_wPznAhVEnKwKHZ50A6AQFjABegQIAhAB&url=https%3A%2F%2Fwww.octe.ca%2Fdownload_file%2Fforce%2F1158%2F411&usg=AOvVaw1au6GfhlmdobuZR8n43Erm
01:28 PM Tom_L: pdf
01:31 PM polprog: thats not the compound on the label
01:31 PM Tom_L: it's still nasty stuff
01:34 PM polprog: cas 7772-99-8 so thats not the dihydrate
01:34 PM polprog: ill try to find a safety card for it
01:34 PM polprog: https://www.fishersci.com/shop/msdsproxy?productName=AC196980025
01:36 PM Tom_L: similar warnings
01:39 PM polprog: yeah
10:35 PM Tom_L: mighty quiet night