#garfield Logs

Sep 10 2018

12:39 AM rue_mohr: furrywolf, prolly an electric vehicle, like a floor cleaner or old "forklift"
09:33 PM zhanx-: Evening
09:50 PM rue_mohr: hey
09:58 PM zhanx-: Remodeling the house a bit
09:58 PM zhanx-: While waiting on parts
10:19 PM rue_mohr: is the power supply your using just 12V?
10:19 PM zhanx-: 12v psu out of a pc
10:31 PM rue_mohr: ok, are you using just the 12V or the 5V too?
10:36 PM rue_mohr: for making DC servos that use a pot for feedback, I wonder how I can set up a torque-relief for overrotation
10:43 PM zhanx-: 12v only
10:44 PM zhanx-: Ratching slip joint
10:45 PM rue_mohr: hmm,
10:46 PM rue_mohr: on another project, I want to make an electrostatic amplifier (for picking up and hearing electrical noise)
10:46 PM rue_mohr: if I have a 1Mhz amp, and use a gain of 100
10:46 PM rue_mohr: its only good to 10Khz
10:46 PM rue_mohr: :/
10:48 PM rue_mohr: maybe I should multistage it
10:49 PM zhanx-: Can't help with that
10:50 PM rue_mohr: lm324 is 100db and 1Mhz
10:50 PM zhanx-: Been doing lots of drywall work
10:50 PM rue_mohr: so, if I do two 20x stages
10:50 PM rue_mohr: I get a gain of 400, and a rolloff of...
10:50 PM zhanx-: What's the loss in quality?
10:51 PM rue_mohr: 50Khz
10:51 PM zhanx-: For every db gained ?
10:51 PM rue_mohr: ok, if I dont mine a 20Khz rolloff,
10:52 PM ffurrywol: that reminds me, I should fix my kenwood L07m audio amps.
10:52 PM rue_mohr: I can get a gain of 2500 in the two stages
10:52 PM rue_mohr: zhanx-, thre is a "GBP" gain/bandwidth product"
10:52 PM rue_mohr: its 1Mhz
10:52 PM ffurrywol: they're back from when manufacturers were competing on quality, not just price... 150W RMS audio amps
10:53 PM ffurrywol is now known as furrywolf
10:53 PM rue_mohr: if you have a gain of 1000, your signal will start to be attenuated at 1khz
10:53 PM furrywolf: now, they're _audio_ amps... want to guess what the bandwidth is?
10:53 PM rue_mohr: furrywolf, what happened to them?
10:54 PM rue_mohr: isn't 1Mhz kinda typical for lots fo audio amps?
10:54 PM furrywolf: one blows the main fuse, the other blows the control board fuse. I've done no diagnostics beyond that.
10:54 PM zhanx-: I have a working Kenwood l07m
10:54 PM zhanx-: It was given to me
10:54 PM furrywolf: no, 20khz is typical for audio amps. lol
10:54 PM rue_mohr: furrywolf, oh easy, they popped the IRFZ44 in the power converters
10:54 PM furrywolf: zhanx: one or two?
10:54 PM zhanx-: 1
10:54 PM furrywolf: they're a lot more useful in pairs. lol
10:54 PM zhanx-: It's on the shelf so yea
10:55 PM zhanx-: No speakers for it
10:55 PM furrywolf: it's mono, only need one. lol
10:55 PM furrywolf: in any case, the later versions were DC-600Khz -3db. for audio.
10:55 PM zhanx-: Lol you can tell i looked at it so much then
10:56 PM furrywolf: hence why they're more useful in pairs. heh.
10:56 PM zhanx-: I got that and a dual tape deck
10:56 PM zhanx-: Not sure where that is
10:57 PM furrywolf: want to get rid of the l07m?
10:57 PM zhanx-: No I am wanting to get speakers for it
10:58 PM zhanx-: My dad had one so I know how they sound
10:58 PM zhanx-: But his was records only
10:58 PM furrywolf: if it is an l07m, and you're not getting the model number wrong, it's a mono amp. one channel. you always use them in pairs, at least if you have two ears.
10:59 PM zhanx-: Is there a stereo one?
11:00 PM furrywolf: not with that model number
11:00 PM zhanx-: K the model is right
11:00 PM furrywolf: https://specialistdivision.files.wordpress.com/2015/08/kenwood-l-07m.jpg looks like that?
11:00 PM zhanx-: Complete with gold plated speaker jack
11:01 PM rue_mohr: hah, wouldn' that screw with people, release the different amps with the same model number in two different areas
11:02 PM zhanx-: No the front has a jack and controls on it
11:02 PM rue_mohr: https://www.bcit.ca/apprenticeship/students/training/electrical+apprentice
11:03 PM rue_mohr: I'm screwed for 4th year school
11:03 PM furrywolf: go double-check the model number. :P
11:03 PM zhanx-: K
11:04 PM zhanx-: L07c my bad
11:04 PM zhanx-: Only 1 letter off
11:06 PM zhanx-: Rue thought you were done with school
11:06 PM furrywolf: the l-07c is the preamp for a pair of l-07m power amps. it doesn't have its own amplifier.
11:06 PM rue_mohr: no I'v not done 4th yet
11:06 PM rue_mohr: I have the hours, just not the time to do the school
11:07 PM rue_mohr: and their changing the program all around now
11:07 PM zhanx-: Fun
11:07 PM rue_mohr: I'm supposed to finish before Sep 2020 or I'm screwed for the stuff I'v already done
11:07 PM furrywolf: you use the l-07c to control power amps... it's pretty useless on its own.
11:07 PM zhanx-: Great
11:08 PM zhanx-: So my trade was crap then
11:08 PM furrywolf: now you need a pair of l07ms to hook up to it. :P
11:08 PM zhanx-: And speakers
11:09 PM zhanx-: I plan on doing whole house stereo
11:09 PM furrywolf: https://i.ebayimg.com/00/s/MTIwMFgxNjAw/z/pasAAOSwn4Vbi7M6/$_1.JPG like that
11:10 PM zhanx-: K
11:11 PM zhanx-: I just dropped 500 on stuff to repair and remodel and 800 on the kids for school
11:11 PM zhanx-: So that has to wait
11:11 PM zhanx-: I do plan on getting a bunch of in ceiling speakers also
11:12 PM furrywolf: I only have a stereo in my living room... I don't spend much time in other rooms.
11:12 PM zhanx-: Rue I pulled 1000 deer o
11:13 PM furrywolf: plus, my living room is loud enough to be heard anywhere in the house/property/neighborhood....
11:13 PM zhanx-: Feet of cat5 at home today
11:13 PM zhanx-: Darn phone
11:13 PM rue_mohr: deer feet..
11:13 PM rue_mohr: thats about 3" right?
11:13 PM zhanx-: Lol
11:13 PM rue_mohr: :)
11:13 PM rue_mohr: yea, runs add up eh?
11:13 PM zhanx-: More like 5"
11:13 PM furrywolf: have my JBL 4312 control monitors on my desk, my 14" sansuis on the wall on either side, and my 16" sansuis and 12" pioneers on the back wall, with a total of 1200W RMS of amplifier power...
11:14 PM zhanx-: Yes they do
11:14 PM rue_mohr: deer dont have 5 feet, <thats not a foot>
11:14 PM zhanx-: I have a closet in the laundry room I pulling everything to
11:14 PM rue_mohr: yup
11:15 PM furrywolf: I'm pretty much all-wireless now
11:15 PM rue_mohr: ugh
11:15 PM zhanx-: 2 cat5 per room and 2 speaker cat5 1 extra
11:15 PM rue_mohr: yep
11:15 PM zhanx-: Furry I overloaded my wifi
11:16 PM rue_mohr: ok I have a design for a 2500x amp
11:16 PM rue_mohr: good to 20Khz
11:16 PM rue_mohr: that should be enough to hear any kinda electrostatic signal of anything
11:16 PM zhanx-: Now I am doing mine with wifi for the smart stuff. Cables for what I can