[QUOTE=ROBO_DONUT;34092070]I'm fine with it. He struck me as a bit of a toolbag.
Moreso after watching that video.[/QUOTE]
I dunno he hates RWJ that's a big plus in my book.
Been desoldering parts from the boards I got out of the Panasonic TV, lots of goodies!
[img_thumb]http://i.imgur.com/pCTcZ.jpg[/img_thumb]
All of the ICs you see there had to be soldered from the board, none were in sockets.
[QUOTE=ddrl46;34095022]All of the ICs you see there had to be soldered from the board, none were in sockets.[/QUOTE]
How did you do that? Do you have a hot air solder gun?
I always use a paintstripper for that:
[img]http://img.cbcdn.net/products/101093/verfstripper-h-1600.jpg[/img]
I should get myself a decent hot air gun, though... The paintstripper just blows air all over the place. And no decent temperature control either.
[QUOTE=ddrl46;34095022]Been desoldering parts from the boards I got out of the Panasonic TV, lots of goodies!
[img_thumb]http://i.imgur.com/pCTcZ.jpg[/img_thumb]
All of the ICs you see there had to be soldered from the board, none were in sockets.[/QUOTE]
Soldering iron bros!
[QUOTE=masterburner;34095140]How did you do that? Do you have a hot air solder gun?
I always use a paintstripper for that:
[img]http://img.cbcdn.net/products/101093/verfstripper-h-1600.jpg[/img]
I should get myself a decent hot air gun, though... The paintstripper just blows air all over the place. And no decent temperature control either.[/QUOTE]
I was able to use a standard hand desoldering pump and my 50W iron because they used nice leaded solder instead of the lead-free crap.
So, could anyone tell me what happened with photonicinduction? Why did he close his account?
[QUOTE=Val67;34115873]So, could anyone tell me what happened with photonicinduction? Why did he close his account?[/QUOTE]
[QUOTE=masterburner;34091874]Alright, here are the videos of photon explaining everything:
Part 1: [url]http://www.youtube.com/watch?v=yjvskVvaZ0s&context=C3ae1df9ADOEgsToPDskIZPHRuMm9zVEZOnL7B-6tB[/url]
Part 2: [url]http://www.youtube.com/watch?v=SGfYfn-MNO0&feature=context&context=C3ae1df9ADOEgsToPDskIZPHRuMm9zVEZOnL7B-6tB[/url]
I think he made a wise decision.[/QUOTE]
Also I blew up an IRF3707 by using it in a boost converter, I should have known better what with its 30V VDS rating :-(.
I can't see the videos, they were deleted
[QUOTE=Val67;34117170]I can't see the videos, they were deleted[/QUOTE]
He gets married, too much work to keep up with youtube, accusations of doing dangerous stuff (lasering at planes), other big youtube channels copying his work and making profit off of it
I don't know where else to ask this, but I am a n00b :P
Okay, I was soldering (I am a beginner, doing for a science project), and I breathed in the fumes for 15 minutes.
I did this today and 2 weeks ago. I just found out it has lead in it. Is this bad?
[QUOTE=Hack;34120829]I don't know where else to ask this, but I am a n00b :P
Okay, I was soldering (I am a beginner, doing for a science project), and I breathed in the fumes for 15 minutes.
I did this today and 2 weeks ago. I just found out it has lead in it. Is this bad?[/QUOTE]
Yes and No, the fumes are soldering flux that evaporates when it comes into contact with the hot iron. While it's not directly dangerous, prolonged exposure is know to cause asthma. But for that you need to breathe it in regularily over months.
Lead only is dangerous when the iron's temperature is way too high, the solder won't evaporate, but tiny particles will be carried with the fumes and get into your body. If you had lead poisoning, you'd notice it, as one of the symptoms is diarrhea.
[QUOTE=DrLuke;34121579]Yes and No, the fumes are soldering flux that evaporates when it comes into contact with the hot iron. While it's not directly dangerous, prolonged exposure is know to cause asthma. But for that you need to breathe it in regularily over months.
Lead only is dangerous when the iron's temperature is way too high, the solder won't evaporate, but tiny particles will be carried with the fumes and get into your body. If you had lead poisoning, you'd notice it, as one of the symptoms is diarrhea.[/QUOTE]
I won't have any health effects from what I did, right?
[QUOTE=Hack;34121745]I won't have any health effects from what I did, right?[/QUOTE]
None that you'll notice, it wont kill you but best to try and avoid it.
I generally keep a window open when i am soldering.
[QUOTE=Hack;34121745]I won't have any health effects from what I did, right?[/QUOTE]
You'd have to work with this all day for years before you'd even begin to notice any effects.
Just keep some decent ventilation and you'll never ever have to worry.
Opening a window and having a small computer fan running by your desk (blowing all the fumes away) usually works fine.
Meh, just don't breath the smoke directly. Don't stick your nose right above the iron and you're fine. I've been soldering for years now and I still seem to function just fine... If you need to solder in an awkward position and you can't avoid the fumes going to your nose, just hold your breath for a few seconds.
If you need to do a LOT of soldering in one go, just open a window or door. No need for all kinds of fancy ventilation stuff.
Need to avoid solder fumes while you're doing some quick soldering? Blow gently on the joint as you solder it! Works okay if you've got a small soldering job to do, at least.
[QUOTE=Lapsus;34130894]Need to avoid solder fumes while you're doing some quick soldering? Blow gently on the joint as you solder it! Works okay if you've got a small soldering job to do, at least.[/QUOTE]
It can also cause it to cool too quickly leaving a cold solder joint.
You're blowing too hard :v:
Not like you can't stop once the flux boils off, and then remove the heat anyways.
[QUOTE=Lapsus;34131196]You're blowing too hard :v:
Not like you can't stop once the flux boils off, and then remove the heat anyways.[/QUOTE]
By that time the component you were soldering has probably already overheated.
Is there some kind of sweet package deal I can get to get myself started on this stuff?
I've done some of this in college, so I have an idea of what to do, but I don't really know what all I should get.
Some kind of starter pack would be nice.
[QUOTE=slayer20;34158135]Is there some kind of sweet package deal I can get to get myself started on this stuff?
I've done some of this in college, so I have an idea of what to do, but I don't really know what all I should get.
Some kind of starter pack would be nice.[/QUOTE]
Starter packs aren't that great.
Ask chryseus, if he has time I'm sure he'll whip you up a customized list of stuff to get.
Add me on steam, everyone loves my parts lists.
Need help with this one:
It is a Single stage transistor amplifier with a shared shorted emitter (unsure about english terms here). But there is a generator and a load added.
[IMG]http://i41.tinypic.com/11w3chy.jpg[/IMG]
I must find the Voltage over [b]RL[/b]. I know all the R values (including Rg, rπ, and r0) and have calculated the in- and out resistances, and the Av.
Any help would be appreciated. Even links or terminology in english (so I can google it). My book doesn't explain how to deal with generators and loads in this circuit.
[QUOTE=Rad McCool;34160638]shared shorted emitter (unsure about english terms here).[/QUOTE]
Common emitter amplifier.
Thanks!!
[QUOTE=Rad McCool;34160638]Need help with this one:
It is a Single stage transistor amplifier with a shared shorted emitter (unsure about english terms here). But there is a generator and a load added.
[IMG]http://i41.tinypic.com/11w3chy.jpg[/IMG]
I must find the Voltage over [b]RL[/b]. I know all the R values (including Rg, rπ, and r0) and have calculated the in- and out resistances, and the Av.
Any help would be appreciated. Even links or terminology in english (so I can google it). My book doesn't explain how to deal with generators and loads in this circuit.[/QUOTE]
This is called a capacitively coupled common emitter amplifier with voltage divider base bias and emitter degeneration (negative feedback) with bypassed AC feedback.
(or just a common emitter)
The collector voltage (approximate does not include intrinsic emitter resistance): VC = (IE * RE)
Voltage over RL = VC * (RL / (RC + RL)) just like a voltage divider
In practice however you would usually have a capacitor and resistor providing the AC feedback not just a capacitor since this particular circuit has a very high AC gain which will result in distortion of the signal.
Oh and your input cap is the wrong way around, in my experience you usually have the + side towards the input, although it may not really matter.
As for your question, I think the open circuit gain for DC and low frequencies is going to be ~R[sub]c[/sub]/R[sub]e[/sub] as long as R[sub]e[/sub] is largish. C[sub]e[/sub] changes things for higher frequencies a bit. For sufficiently high frequency AC, it is going to look like a short to ground, and then the gain is the product of the transconductance and R[sub]c[/sub], or g[sub]m[/sub]R[sub]c[/sub].
For the load, I think you could approach it one of two ways. I think you could either calculate the output impedance of the amplifier and treat the entire amp/load circuit as a big voltage divider (gain=Z[sub]load[/sub]/(Z[sub]amp,output[/sub]+Z[sub]load[/sub])) or you could combine R[sub]load[/sub] with R[sub]c[/sub] and the equation becomes v[sub]load[/sub](t)/v[sub]g[/sub](t)=g[sub]m[/sub]/(1/R[sub]c[/sub]+1/R[sub]load[/sub]) for reasonably high frequency AC.
I'd really recommend you get more opinions, though. I've gotten really bad with analog stuff, and I've made [i]a ton[/i] of assumptions here that may not be valid, without knowing the precise part values and operational frequencies.
[QUOTE=Chryseus;34160808]The collector voltage (approximate does not include intrinsic emitter resistance): VC = (IE * RE)
Voltage over RL = VC * (RL / (RC + RL)) just like a voltage divider
[/QUOTE]
IE = IC right?
[QUOTE=Rad McCool;34161043]IE = IC right?[/QUOTE]
For DC, yes, approximately (neglecting base current, which should be small), but not for AC.
AC current can pass through the coupling capacitor and load, so i[sub]e[/sub](t) is not necessarily equal to i[sub]c[/sub](t). If you're interested in the AC gain of the circuit, then you cannot make the assumption that the two are equal.
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