#garfield Logs

Oct 26 2021

12:28 AM rue_mohr: so I just designed up an optically isolated audio ...isolator
12:35 AM rue_mohr: and it works
12:35 AM rue_mohr: wasn't able to do that before!
12:40 AM rue_mohr: polprog, ghostprog? hmm
12:40 AM polprog: Spooky month
12:40 AM polprog: It sounds weird i know
12:41 AM polprog: Good job on that optoisolator
12:44 AM rue_mohr: yea that was an interesting one
12:44 AM rue_mohr: I'm trying to work with "Every circuit is simple, you have input signals, and output signals, put what you need in the middle to make it happen"
12:45 AM rue_mohr: if you can understand enough about the things not doing what you want, you can understand what to add to make them do it.
12:45 AM rue_mohr: and how I wish it were all that easy
12:46 AM rue_mohr: no distortion to 15kHz too!
12:46 AM rue_mohr: I'm gonna make a few, my modem-transformer ones have moderate loss
12:49 AM rue_mohr: I'v tried to make those before and gave up thinking the opto-isolators just didn't have the bandwidth
12:49 AM rue_mohr: so that feels super cool
01:53 AM polprog: Its great!
01:53 AM polprog: I should go back to building simple stuff like that. Maybe i could do PCM audio over these fibre transceivers
01:58 AM rue_bed: haha, I'm browsing thru an old magazine, and
01:59 AM rue_bed: magazine: "midnight engineering" publisher: "Bill Gates" Phone: 303-491-9092
01:59 AM rue_bed: I have to wonder
01:59 AM rue_bed: polprog, consider 1 bit audio too
01:59 AM polprog: Hmm yeah
01:59 AM rue_bed: or FM
02:00 AM rue_bed: PLLs are good practise
02:00 AM polprog: ah i could go back to my pll project
02:01 AM polprog: These transceivers have a minimum frequency they have to operate at (or rather, a maximum off time due to AGC in the receiver)
02:01 AM polprog: And they only transmit logic levels
02:01 AM rue_bed: yup
02:01 AM rue_bed: FM is perfect then
02:01 AM rue_bed: you know your freq range
02:02 AM rue_bed: center your signal on it
02:02 AM rue_bed: dont exceed 2f
03:15 AM polprog: yeah
03:15 AM polprog: wow that python script blew up
03:15 AM polprog: i was sure that there are better tools
03:15 AM polprog: and there are
03:16 AM polprog: tools for viewing ROMs as graphics, for analysis and "eyeballin' "
03:16 AM polprog: but i think these are mostly for a certain platform (like GameBoys) and known only in the repsective scenes
03:17 AM polprog: then Matplotlib twitter account rt'd my screenshot of that Ati ROM
03:17 AM polprog: hmm
04:36 AM Tom_L: that's cool rue_mohr
10:05 AM rue_shop3: polprog, :)
10:05 AM polprog: :)
10:08 AM polprog: https://polprog.net/blog/romview/
01:23 PM aandrew: rue_shop3: you don't happen to have a handy list of standard capacitor values, do you? Do they follow the E24/E96 that resistors follow?
04:12 PM polprog: they follow every second value in e24
04:12 PM polprog: i think its E12 series
05:46 PM aandrew: really, it's just 12 values per decade?
07:32 PM Tom_L: got one new ear
07:33 PM Tom_L: got driver today http://tom-itx.no-ip.biz:81/~webpage/cnc/rotary/mount/Gecko1.jpg
08:15 PM rue_mohr: hi
08:16 PM rue_mohr: aandrew, sounds right
08:17 PM rue_mohr: 1, 1.5, 2.2 3.3 4.7, 8.2,
08:17 PM rue_mohr: for electrolytic anyhow
08:18 PM rue_mohr: 6.8? I think 6.8 should be in there
09:05 PM aandrew: yeah 6.8 is there too
09:05 PM aandrew: I'm trying to (finally) get my RCLs organized, I have had film negative binder sheets for years but never used 'em
09:06 PM aandrew: there's like 700 E92 values so I'm obvioulsy not going to have a space for every one
09:06 PM aandrew: but trying to find a reasonable list
10:28 PM rue_mohr2: well
10:28 PM rue_mohr2: for resistors
10:28 PM rue_mohr2: I go by power,
10:29 PM rue_mohr2: [gold/silver/black], brown, red, orange, yellow, green, blue
10:29 PM rue_mohr2: but I have a set of ranges for caps
10:29 PM rue_mohr2: I'll see what it is for most of the powers
10:30 PM rue_mohr2: esp cause I have some crazy values
10:34 PM Tom_L: i did find a 47 ohm for the driver after some diggin
10:50 PM Tom_L: maybe i'll hook the driver up tomorrow
10:50 PM Tom_L: spent this afternoon getting a hearing test etc
11:03 PM rue_mohr2: oh, it didn't come with some current set resistors?