hehe, I have a very similar groove in my tooth. I try to use it as little as possible now, but old habits die hard. Most people have a hard time believing how much control and repeatability I posses with this technique. Every once in a while I run accross someone with the same tell-tale trait. We should start a club
D'oh
I decided that I wanted to look at the output waveform produced by the little circuitI had that allows 120V soldering irions to be used on 240v mains.......just a thyristor circuit really.
So I clipped my 'scope's probe A to one of the outputs, and scope ground to the other. No need to check the polarity of course.
After the initial spark ans smoke of course the circuit was toasted, but at least the 'scope still worked.
The worst part is that my workbench area is in a closed off corridor that connects to the property next door. When the properties were subdivided, someone stuffed up, and the power to this area is fed by next door's meter! So when I hooked up my 'scope, I blew a mains fuse - next door!
Being too embarassed to explain to my neighbour what had happened (she would just worry too much...), I just ran an extension cord back there to restore power.........the fuse is still blown, after nearly 3 years, so I guess that circuit isn't too important to my neighbour..
I decided that I wanted to look at the output waveform produced by the little circuitI had that allows 120V soldering irions to be used on 240v mains.......just a thyristor circuit really.
So I clipped my 'scope's probe A to one of the outputs, and scope ground to the other. No need to check the polarity of course.
After the initial spark ans smoke of course the circuit was toasted, but at least the 'scope still worked.
The worst part is that my workbench area is in a closed off corridor that connects to the property next door. When the properties were subdivided, someone stuffed up, and the power to this area is fed by next door's meter! So when I hooked up my 'scope, I blew a mains fuse - next door!
Being too embarassed to explain to my neighbour what had happened (she would just worry too much...), I just ran an extension cord back there to restore power.........the fuse is still blown, after nearly 3 years, so I guess that circuit isn't too important to my neighbour..
One of the first experiments was classic water electrolysis. We used graphite rods from post-mortem 4.5v flashlight batteries, 5 in parallei. Of course conductivity of drain water at 12v batt charger was not enough high so we decided to mix some salt and acetic acid to electrolyte. Results: plenty of chlorine, difficulties breathing downwind of apparatus. We decided to chech if we get any hydrogen, burning stick to hydrogen pipe: Loud explosion and half of the electrolyte flies around(it was tasting salty)
And how long it takes to learn wich side of soldering iron is hot? I remember when i was teenager that i had at least one blister in my fingers all the time.
Not so long time ago i was repairing some industrial apparatus that had 0-10mA input and 230v line input at other side of edge connector. After playing around with it couple of times and plugging-unpluggind 230v cord to it i managed to mix up connectors(identical ones ) and plug 230v to 10mA input:
Burning copper foils flying around, dozen of IC´s "uncapped" and plenty of papers got to fire after burning stuff landing over them.
Called to customer after that and told that it seems to be uneconomical to fix this one
Got shot by BC337, install it wrong way to high-power amp and plastic to92 case flies around in pieces, hitting my forehead.
Dipped tantalums, I think everyone has had experiences with these Nowadays I use at least 2 meters extension cord when i have replaced electrolytics to anything, they sometimes go off like missiles.
Maybe best of mine:
I was using super-low viscosity syanoacrylate glue and find out that nozzle of bottle was slightly clogged. Well, hard squeeze should clear it....Yeap it does, resulting superglue to spray out with pressure to every direction. I had droplets of glue everywhere, resulting that got glued from my left hand to my cellphone, cellphone to ear, eyeglasses to nose, right hand to table and socs and soles to floor.... Superglue attach anything to SKIN in 2 seconds, but if skin is not involved it stays liquid on your screwdrivers at least 2 hours just waiting for your sweaty palm to catch on
Sorry for typos, what can you expect from guy who has to grab hot side of iron for dozens of times before learning
And how long it takes to learn wich side of soldering iron is hot?
I remember when i was teenager that i had at least one blister in my fingers all the time.Not so long time ago i was repairing some industrial apparatus that had 0-10mA input and 230v line input at other side of edge connector. After playing around with it couple of times and plugging-unpluggind 230v cord to it i managed to mix up connectors(identical ones
) and plug 230v to 10mA input:Burning copper foils flying around, dozen of IC´s "uncapped" and plenty of papers got to fire after burning stuff landing over them.
Called to customer after that and told that it seems to be uneconomical to fix this one
Got shot by BC337, install it wrong way to high-power amp and plastic to92 case flies around in pieces, hitting my forehead.
Dipped tantalums, I think everyone has had experiences with these
Nowadays I use at least 2 meters extension cord when i have replaced electrolytics to anything, they sometimes go off like missiles.Maybe best of mine:
I was using super-low viscosity syanoacrylate glue and find out that nozzle of bottle was slightly clogged. Well, hard squeeze should clear it....Yeap it does, resulting superglue to spray out with pressure to every direction. I had droplets of glue everywhere, resulting that got glued from my left hand to my cellphone, cellphone to ear, eyeglasses to nose, right hand to table and socs and soles to floor.... Superglue attach anything to SKIN in 2 seconds, but if skin is not involved it stays liquid on your screwdrivers at least 2 hours just waiting for your sweaty palm to catch on
Sorry for typos, what can you expect from guy who has to grab hot side of iron for dozens of times before learning
Around 11 or so I got my first electric RC car kit (Team Associated RC10T). My dad put it together for me but I fiddled with it - especially the electronics. So i got myself a more powerful motor one day and soldered the proper wires, caps, and diode to the tabs on the endbell of the motor, charged up my 7.2V NiCd battery and took her out for a spin. I eased onto the throttle and the car started sputtering and jerking forward violently. I knew something was wrong but felt the need to go full throttle. I did and heard this very loud fizzzzz sound coming from the car. Then a very bright light came from the motor area, followed by a small pop, and then a small fire. It just so happens that I had installed a schottky didode in reverse polarity across the motor! The ensuing fire melted the caps and the wire insulation I had just installed too.
So the full current of a 7.2V NiCd pack through a forward biased schottky diode makes some nice fireworks My little car never smelled the same after that either.
So the full current of a 7.2V NiCd pack through a forward biased schottky diode makes some nice fireworks
My little car never smelled the same after that either.
I remember when I was 13 and had just made my first 2 transistor 2Hz multivibrator/flashing LEDs circuit and was deciding what to do with it ....................... "I know what, I'll connect it across my head" said I to myself. Quite an experience, connected across my temples my vision was flashing light/dark in time with the LEDs. Haven't been the same since some would say.
The year was 1969...I was 8 years old when I was given an old diy crystal radio set built by a relative years before. It worked (past tense) great. I connected a speaker robbed out of an old radio across the diode (an old military surplus metal jacketed monster) and was puzzled as to why it didn't work like it did with the headphone. So I went to the person that always had the answer..MOM..and asked why the radio in the house could power a speaker but mine couldn't. She said "The radio in the house plugs in and yours doesn't"...clearly she did not think through the ramifications of her answer. I promptly went out into the garage, scounged up a power cord and wired it across the diode in parallel with the speaker...and plugged it in . After my ears quit ringing from the load "crack", and I put out the flaming speaker, I noticed the big diode was missing. I looked around and found it completely imbedded in a wall stud. The radio never played again, and Mom, after finding out what I had done answered all future electronic querys with "I don't know".
Casey
. After my ears quit ringing from the load "crack", and I put out the flaming speaker, I noticed the big diode was missing. I looked around and found it completely imbedded in a wall stud. The radio never played again, and Mom, after finding out what I had done answered all future electronic querys with "I don't know".Casey
I was 16, I decided to try and make some screwdriver type booze. A week and a gallon of orange juice with added sugar, yeast, and the mouth of the jug connected to a large balloon later I had some very peculiar orange juice/beer/wine/malt liquor. It sure wasnt screwdriver, but it did have alcohol.
Gotta just say - Great thread, hours of fun to read!
When I was about 15 I had an immense amount of fun with a 24VDC motor, actually all connected up correctly (on this occasion) to a properly grounded and fused power supply. Hours of fun attaching various different items to the shaft of the motor and watching them whizzing round. I even managed to attach razor blades to it and cut up things without injury.
Sadly this soon lost it's appeal and I was searching for something bigger and far more unsafe! Luckily for me I found just the thing, an old washing machine in the garden shed with one of those humongous dirty great big mains electric motors in. heaven! I was intelligent enough to bolt the thing down to a large chunk of wood with breeze blocks on it before commencing. Finally figured out the wiring after several mains shocks and a few sparks and bangs. that thing REALLY spun I can tell you.
All was well until I decided it would be great to fit a propellor on it and hold it over my head....
hmmmm the rest is history.
Fortunately the lead wasn't long enough to get me more than a few feet up before the power failed but I can say that once I left the ground I spun more than the motor did!
I'm still alive writing this aren't I?! The interesting thing is, I got my pilot licence about 5 years later!
When I was about 15 I had an immense amount of fun with a 24VDC motor, actually all connected up correctly (on this occasion) to a properly grounded and fused power supply. Hours of fun attaching various different items to the shaft of the motor and watching them whizzing round. I even managed to attach razor blades to it and cut up things without injury.
Sadly this soon lost it's appeal and I was searching for something bigger and far more unsafe! Luckily for me I found just the thing, an old washing machine in the garden shed with one of those humongous dirty great big mains electric motors in. heaven! I was intelligent enough to bolt the thing down to a large chunk of wood with breeze blocks on it before commencing. Finally figured out the wiring after several mains shocks and a few sparks and bangs. that thing REALLY spun I can tell you.
All was well until I decided it would be great to fit a propellor on it and hold it over my head....
hmmmm the rest is history. Fortunately the lead wasn't long enough to get me more than a few feet up before the power failed but I can say that once I left the ground I spun more than the motor did!
I'm still alive writing this aren't I?! The interesting thing is, I got my pilot licence about 5 years later!
i took the breeze blocks off and screwed on 2 big door handles to the underneath and held the thing over my head. I flicked the mains switch on the extension lead with my foot to start it.
It lifted me off the ground about 2 feet but the mains lead came off, I was spinning round underneath it at around 400RPM at a guess... I dropped it, hit the floor blood everywhere from a lot of cuts, (Iwas on concrete) the motor broke as well.
Didn't break any bones but I did break both eardrums being shouted at by my Dad, who called me something along the lines of "a silly billy"! Or perhaps it was less polite than that.... come to think of it, yes I think it was a great deal less polite than that actually!
Ha, happy days!
It lifted me off the ground about 2 feet but the mains lead came off, I was spinning round underneath it at around 400RPM at a guess... I dropped it, hit the floor blood everywhere from a lot of cuts, (Iwas on concrete) the motor broke as well.
Didn't break any bones but I did break both eardrums being shouted at by my Dad, who called me something along the lines of "a silly billy"! Or perhaps it was less polite than that.... come to think of it, yes I think it was a great deal less polite than that actually!
Ha, happy days!
Think I was about 13 or 14, to tell the truth I can't remember when the power dropped off, all I can remember was spinning around very fast and dropping the dam thing! We do have some strange ideas when we're young!
The prop was off a microlight, we lived next door to an airfield, still do in fact - the only difference being I now fly proper aircraft, ha ha! (Pic attached).
I dare say at this point I shouldn't mention the occasion when I was about 18 when I tried to weld using a piece of mains cable and a 3 pin plug...... made perfect sense to me, didn't blinkin work though! The results were interesting... smashing!
The prop was off a microlight, we lived next door to an airfield, still do in fact - the only difference being I now fly proper aircraft, ha ha! (Pic attached).
I dare say at this point I shouldn't mention the occasion when I was about 18 when I tried to weld using a piece of mains cable and a 3 pin plug...... made perfect sense to me, didn't blinkin work though! The results were interesting... smashing!
Attachments
Using the microwave to dry sand (speakerproject in a hurry..)which works perfectly fine until you get so confident to stash 4 kg on the rotating glass panel and apparently the moter controling the rotation short outs under the weight and set the whole microwave on fire........, back to being patience...
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