Electrical Engineering V2 - Developers

WOW. this is a 1985 home automation system.... with a touch screen... just amazing. [url]http://imgur.com/a/Jb6jW[/url]

It seems so strange seeing a touch screen before flat screens were a common thing.

I know its stupidly simple, but it was an impulse build and I thought it was fun... :v: [video=youtube;pouFVZmkfw8]http://www.youtube.com/watch?v=pouFVZmkfw8[/video]

I know it's not really EE, but I built my first quadcopter this afternoon and I thought you guys might appreciate this little timelapse of the build: [media]http://www.youtube.com/watch?v=MnuKOZRGg_Q[/media]

Oi, dji Flamewheel F350 buddies!

I finally got my analog PWM to work using a voltage source as the controller. It uses a current source linearly charging a capacitor and 555 timer to create a sawtooth wave and then a comparator to take the voltage and turn it into PWM. There has to be a more straightforward way to do it I would imagine?

You could use a triangle wave to create a constant-phase PWM.

is it safe to charge up a small lipo battery with out a station, and if so;how? I'm thinking of some solar arduino project with a backup battery to last the night. [URL="http://www.dx.com/p/3-7v-500mah-20c-battery-for-rc-helicopter-35608#.U7sBw_l_teQ"]something like this? [/URL]

[QUOTE=scratch (nl);45319700]is it safe to charge up a small lipo battery with out a station, and if so;how? I'm thinking of some solar arduino project with a backup battery to last the night. [URL="http://www.dx.com/p/3-7v-500mah-20c-battery-for-rc-helicopter-35608#.U7sBw_l_teQ"]something like this? [/URL][/QUOTE] No.

I think this ebay seller might have some issue in their system. I bought 25 2x8cm green double sided perfboards, and 10 5x7cm single sided (5 brown, 5 yellow), and they sent 5x yellow, 25x green and... I already got 3 packages in the mail of brown pcbs, amounting to a total of 25. They told me to keep them. Now I've got a lifetime supply of perfboard. If only it was veroboard :v: [editline]7th July 2014[/editline] The loot [t]http://i.imgur.com/ZpCw6sA.jpg[/t]

Imagine the amount of beacons/geo-caches you could build with that.

[QUOTE=LoneWolf_Recon;45320982]Imagine the amount of beacons/geo-caches you could build with that.[/QUOTE] I had never heard of beacon geo-caches. I might build a bunch. Thanks for the idea. Kind of sucks that amateur radio in portugal is dying though. Anacom (like the fcc but in pt) is slowly killing it for some reason. [editline]7th July 2014[/editline] I think I could make a small AM transmitter that people could try and find with an pocket radio.

[QUOTE=TTSDA;45320600]I think this ebay seller might have some issue in their system. I bought 25 2x8cm green double sided perfboards, and 10 5x7cm single sided (5 brown, 5 yellow), and they sent 5x yellow, 25x green and... I already got 3 packages in the mail of brown pcbs, amounting to a total of 25. They told me to keep them. Now I've got a lifetime supply of perfboard. If only it was veroboard :v: [editline]7th July 2014[/editline] The loot [t]http://i.imgur.com/ZpCw6sA.jpg[/t][/QUOTE] Damn, I crave those boards-- everytime I need them, they are gone.

[QUOTE=TTSDA;45320600]I think this ebay seller might have some issue in their system. I bought 25 2x8cm green double sided perfboards, and 10 5x7cm single sided (5 brown, 5 yellow), and they sent 5x yellow, 25x green and... I already got 3 packages in the mail of brown pcbs, amounting to a total of 25. They told me to keep them. Now I've got a lifetime supply of perfboard. If only it was veroboard :v: [editline]7th July 2014[/editline] The loot [t]http://i.imgur.com/ZpCw6sA.jpg[/t][/QUOTE] you got a link to that seller? I'd like some as well :v:

[QUOTE=scratch (nl);45321648]you got a link to that seller? I'd like some as well :v:[/QUOTE] Rather dislike that brown board myself, the traces come of -far- too easily. I got loads of varo board... waste of money, i would much rather use matrix board or just plain perf-board. Varo board is rather bad when it comes to higher voltage or higher current..

I really need to get round to ordering some of that stuff, I just have nothing I want to make permanent.

[QUOTE=nuttyboffin;45321742]Rather dislike that brown board myself, the traces come of -far- too easily. I got loads of varo board... waste of money, i would much rather use matrix board or just plain perf-board. Varo board is rather bad when it comes to higher voltage or higher current..[/QUOTE] What temperature are you soldering at?

[QUOTE=ddrl46;45325613]What temperature are you soldering at?[/QUOTE] far above what i should be. however i never have the trouble with properly made boards.

[QUOTE=nuttyboffin;45325903]far above what i should be. however i never have the trouble with properly made boards.[/QUOTE] Why? There is no reason to go over temperature unless you're soldering a huge thermal mass.

[QUOTE=nuttyboffin;45325903]far above what i should be. however i never have the trouble with properly made boards.[/QUOTE] Well, thats your problem then.

[QUOTE=DrDevil;45325973]Why? There is no reason to go over temperature unless you're soldering a huge thermal mass.[/QUOTE] Because i usually am soldering a large thermal mass. thick wire, large components and so on. [editline]8th July 2014[/editline] [QUOTE=ddrl46;45325994]Well, thats your problem then.[/QUOTE] And it sure is....... Anyone know where to get the copperless perf-board from?

[QUOTE=nuttyboffin;45326063]Because i usually am soldering a large thermal mass. thick wire, large components and so on. [editline]8th July 2014[/editline] And it sure is....... Anyone know where to get the copperless perf-board from?[/QUOTE] You should look into buying an iron with more wattage than. Any 40W iron is able to solder thick wires and large components. With the extra heat you're only putting large stress on the components, easily damaging them.

[URL]https://www.windowsondevices.com[/URL] Microsoft are giving out testing samples of development boards, I'd suggest checking it out if you are interested.

Meh, fuck windows.

[QUOTE=nuttyboffin;45301715]WOW. this is a 1985 home automation system.... with a touch screen... just amazing. [url]http://imgur.com/a/Jb6jW[/url][/QUOTE] I have one of those IR tracking panels. It's just an array of IR LED's and phototransistors that generate X/Y coordinates depending on which light paths are blocked by your finger, then output something like a serial string to the host. I keep telling people who want to build a home automation system. Hoard up on Minitel terminals before they are all recycled and build those into your walls. [img]https://c1.staticflickr.com/5/4129/5060440292_a15f90c191.jpg[/img]

[QUOTE=DrDevil;45327471]Meh, fuck windows.[/QUOTE] I'd agree but you can probably install Linux on it anyway. Those Intel chips on the other hand would be a rather interesting alternative to a full blown atom processor or ARM. [QUOTE=pentium;45327674]I have one of those IR tracking panels. It's just an array of IR LED's and phototransistors that generate X/Y coordinates depending on which light paths are blocked, then output something like a serial string to the host. I keep telling people who want to build a home automation system. Hoard up on Minitel terminals before they are all recycled and build those into your walls. [img]https://c1.staticflickr.com/5/4129/5060440292_a15f90c191.jpg[/img][/QUOTE] What color phosphor ? I would love an amber one. Also for you people in the UK you can get 10% off at Conrad UK on all orders £50 or over, just use the voucher code [b]missuk[/b] when you checkout, valid until next year.

Minitels were available in white/light blue phosphor. Get them while there should still be a few hidden in closets. They're all in France.

[QUOTE=pentium;45327674]I have one of those IR tracking panels. It's just an array of IR LED's and phototransistors that generate X/Y coordinates depending on which light paths are blocked by your finger, then output something like a serial string to the host. I keep telling people who want to build a home automation system. Hoard up on Minitel terminals before they are all recycled and build those into your walls. [img]https://c1.staticflickr.com/5/4129/5060440292_a15f90c191.jpg[/img][/QUOTE] As tempting as that is.... i would rather make it all myself if i were to :) [editline]8th July 2014[/editline] [QUOTE=DrDevil;45326216]You should look into buying an iron with more wattage than. Any 40W iron is able to solder thick wires and large components. With the extra heat you're only putting large stress on the components, easily damaging them.[/QUOTE] Indeed i should..... On the other hand, i spent all my money on 8 of these IGBTs: [del][url]www.mitsubishielectric.com/semiconductors/.../nf/cm300dy-12nf_e.pdf[/url][/del] not bad, 15 Euros each down from 20. these are the ones everyone uses in the -huge- tesla coils ;) EDIT: Oops, i ment these ones: [url]www.mitsubishielectric-mesh.com/products/pdf/cm300dy-24nf_e.pdf[/url]

[QUOTE=Amiga OS;45330744]I'm sure a freedom respecting OS can be shoehorned onto one.[/QUOTE] So what's the advantage of this over a similar ARM board? [editline]9th July 2014[/editline] [QUOTE=nuttyboffin;45328781]As tempting as that is.... i would rather make it all myself if i were to :) [editline]8th July 2014[/editline] Indeed i should..... On the other hand, i spent all my money on 8 of these IGBTs: [del][url]www.mitsubishielectric.com/semiconductors/.../nf/cm300dy-12nf_e.pdf[/url][/del] not bad, 15 Euros each down from 20. these are the ones everyone uses in the -huge- tesla coils ;) EDIT: Oops, i ment these ones: [url]www.mitsubishielectric-mesh.com/products/pdf/cm300dy-24nf_e.pdf[/url][/QUOTE] I'm not very familiar with IGBTs. What's the highest maximum switching frequency one could expect at full load?

[QUOTE=DrDevil;45331557]So what's the advantage of this over a similar ARM board? [editline]9th July 2014[/editline] I'm not very familiar with IGBTs. What's the highest maximum switching frequency one could expect at full load?[/QUOTE] Its bridging the gap between high level processing (with an x86 processor, which is up to personal taste), and low level peripherals. Much to the same that the Pi did. Also, I do believe a significant factor to max switching frequency depends upon the parasitic capacitance across the gate.