Another spontaneous video recorded during a brief moment of peace at work. This pink(ish) pencil sharpener was given to me by Matt. I went as far as I could, but couldn't find a slim enough screwdriver to access the two final screws. The base reveals most of the science though, just a motor and two switches. One as a cover safety interlock and one to activate the motor when a pencil is inserted.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:- http://www.bigclive.com/coffee.htm This also keeps the channel independent of YouTube's advertising algorithms allowing it to be a bit more dangerous and naughty. ... https://www.youtube.com/watch?v=5Ob_ejGM1Yw
Another work light with power bank functionality, but this one has interesting circuitry. It also works very well as a work light, with the run time dependent on your choice of batteries and the intensity setting you use.
A test of the current showed:-
Full = 900mA
Low = 250mA
Flashing = 600mA
Here's a suitable eBay search link to get you started if you want to get one of these:-
https://www.ebay.com/sch/i.html?_from=R40&_nkw=30W+Portable+USB+COB+LED+Flood+Light+Outdoor+Camping+Spot+Work+Lamp+Power+Bank&_sacat=0&LH_BIN=1&_sop=15
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:-
http://www.bigclive.com/coffee.htm
This also keeps the channel independent of YouTube's advertising algorithms allowing it to be a bit more dangerous and naughty.
...
https://www.youtube.com/watch?v=NAoISQaA5jY
A gloriously dumb USB powered NiMH and NiCad battery charger that will guarantee a full charge every time, but only if you're not in a rush. A trashy 500mAh cell will take about a day to charge, while a luxuriously high capacity cell could take most of a week to charge - but will be charged right to the hilt and not be harmed in the process.
The unit uses low current trickle-charging at between 20-30mA to ensure a safe charge at a low enough level to allow the inherent feature of self catalysis of end of charge gas bubbles back into liquid electrolyte with low pressure buildup.
Can also be powered by a 5 or 6V solar panel and will use whatever solar energy there is to put some charge into the cells.
The PCBs can be cascaded with a common power buss to create an array of up to 40 charge positions from a common 1A charger.
Each cell is charged completely independently from the others and has a diode to prevent backfeed when power is removed or there is no solar power available.
Individual LEDs to indicate charging status. Choose whatever LED colour you like. Power indicator LED is optional and can also be any colour of LED.
There are four 3mm mounting holes for feet or for mounting the PCB to a panel. I'd recommend against having the panel loose amongst metalwork on a bench in case the back gets shorted out.
This trickle charging system is perfect for the newer NiMH low self discharge cells. It's basically creating a better than fresh-out-the-pack level of charge.
Here's a link to the gerber zip file for getting PCBs made. YouTube prevents a direct link to a zip file for security reasons, so you will have to copy and paste the link into another browser tab.
www.bigclive.com/NIMH.zip
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:-
http://www.bigclive.com/coffee.htm
This also keeps the channel independent of YouTube's advertising algorithms allowing it to be a bit more dangerous and naughty.
#ElectronicsCreators
...
https://www.youtube.com/watch?v=wVnAH17f4jg
The accountants have clearly had a part in the redesign of the circuitry on this classic Chinese light panel. They are intended for use in ceiling bulkhead fixtures, where the new panel sticks to the steel backplate with magnets. This type of light has no easy way to change a lamp. You will literally have to turn off the power and hook wires into terminal blocks instead.
The earlier versions used buck regulators with no flicker, but the new ones have cheaped out in every way possible, creating a very flickery light that has the classic over-driven LEDs. There is no other explanation for this other than profit above all else.
Given the LED layout I reckon they have used the original LED positions and tracks, but replaced the original single chip LEDs with multi-chip ones to cater for the higher voltage that is better suited to the linear regulators. That would also explain the rogue track passing under the rectifier.
In this video I do several experiments to stop the flicker and reduce the power dissipation to give higher efficiency and a much longer LED life.
Note that a lot of the experiments involve live exposed connections, so suitable precautions should be taken if doing similar experiments.
Supporting the channel with a dollar or two on Patreon helps keep it independent of YouTube's quirks, avoids intrusive mid-video adverts, gives early access, bonus footage and regular quiet Patreon live streams.
https://www.patreon.com/bigclive
#ElectronicsCreators
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https://www.youtube.com/watch?v=V9U2fCE9Sps
A view of the fireworks from the control booth, with this year being a celebration of David Bowie's contribution to music. The music is a custom orchestral arrangement for this show played live. The fireworks are being electrically triggered to cue by the main castle pyrotechnics department.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:-
http://www.bigclive.com/coffee.htm
...
https://www.youtube.com/watch?v=Y4BOGNrFYYg
These effects aren't new, but I thought it was time to take a look at a current model and see what it's like inside.
I'd also noticed that versions are being done for outdoor garden use, and I must admit that when fired up into a tree it's an impressive effect. Like a 3D sea of fairy lights in the tree.
Of course, whether you should be firing lasers at planes and wildlife is debatable, but the divergence and splitting of the laser beam is probably enough to limit the risk of any issues.
The ebay listing I bought this from was a UK warehouse.
http://www.ebay.co.uk/itm/331698940343
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https://www.youtube.com/watch?v=Bsb5X7fbUSw
This is a faulty ground recessed uplighter that was sent for our exploration by Douglas.
It's a classic example of premeditated landfill, with no replaceable lamp and a sealed case to try and stop water getting in.
They are often mounted into a buried enclosure to ensure that anyone who works on them has to kneel on wet ground and fumble in stinky water to try and make a waterproof connection onto a cable that gets shorter every time a fitting is replaced. They're usually powered from panels where all the RCDs/GFCIs have been bypassed to "fix the tripping issues". (Not a good thing.)
If working on this type of light it's VERY important to ensure power is properly isolated. That can sometimes be difficult when they are fed from random panels and are powered but not lit. Water and electricity are a bad combo for humans.
You can see this type of light littering the pavements of cities and "architectural" areas. They either shoot light pointlessly into space while dazzling pedestrians, or put blotchy skidmarks of light up the side of buildings. They are notable for flickering gently as their corroded LEDs light the internal drops of water on their lens, and occasionally emitting steam from their submerged electrical connections.
You may have noticed I'm not a fan of this type of light. But they do have their place if used as low intensity marker lights, with low voltage power supplies and easily replaced cables going to a nearby pillar.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:-
http://www.bigclive.com/coffee.htm
This also keeps the channel independent of YouTube's advertising algorithms allowing it to be a bit more dangerous and naughty.
...
https://www.youtube.com/watch?v=4goqsDGro7w
Compared to the generic eBay units, this temperature controller is much better built and uses traditional power components and an external high current relay.
The HVAC techs can judge will be the true reference if this type of module is reliable or not, as they may have come across them in use.
The power supply is a traditional potted 2VA transformer, and the external relay means that when it does inevitably fail due to the number of switching cycles, it can be swapped easily without messing around with the controller and settings.
The circuit design is traditional and very time-proven with good filtering on the thermistor input.
This particular unit is a heating controller that could be used directly with resistive heating loads.
It's notable that the PCB is a standard unit with the provision for two thermistors (plus circuitry for a third) and the capability of driving up to three external relays. It has provision on the module for a fourth button and a sounder.
These are normally quite expensive, even on eBay, and I lucked out with a more affordable one being sold as a "refrigeration controller" when in fact it turned out to be a heating version.
The display unit normally shows the measured temperature, but if the button is pressed briefly it flashes the set temperature and allows the user to adjust it within a range that has been determined by the installer.
To program the unit the installer or service engineer holds the set button in for six seconds. When E1 is displayed the set button can be used to step through the options and the up/down buttons used to adjust them as follows.
E1. The lowest temperature that can be set by the user.
E2. The highest temperature that can be set by the user.
E3. Hysteresis - the number of degrees from the set value that the unit activates.
E4 Delay start - a time from zero to ten minutes that avoids frequent cycling of the load.
E5 Thermistor calibration - allows the accuracy to be adjusted vs a calibrated thermometer.
C1 Units of measurement - Celsius or Fahrenheit.
If no button is pressed for ten seconds the unit stores the new settings and reverts back to its normal display.
The hysteresis setting is to avoid rapid cycling of the load by adding a few degrees between on and off. If hysteresis is set to 3 degrees and the set temperature is 18 degrees then the unit will turn off the heater when it reaches 18 degrees, but not turn it back on until the temperature drops to 15 degrees. (18 minus the hysteresis value.)
The delay start is a time setting to allow a load like a compressor to equalise pressure to reduce the risk of stalling if cycled off and on quickly, and also to reduce the stress on equipment caused by frequent starting. In the case of a heating unit like this one it may be set to zero.
Let me know if you've come across these in the wild, and how reliable they are.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:- https://www.bigclive.com/coffee.htm
This also keeps the channel independent of YouTube's algorithm quirks, allowing it to be a bit more dangerous and naughty.
#ElectronicsCreators
...
https://www.youtube.com/watch?v=VTXI-kvEjnY
During a spate of ozone investigation I bought a few different rechargeable ozone generators intended for deodorising cupboards, wardrobes and small rooms, and also keeping fridges sterile by killing surface bacteria.
One works really well, but another was defective from the start and this one started off OK despite some design weirdness, but then failed with a faint crackling noise.
In this video I reverse engineer it, find the cause of the problem affecting many of these units and hack it to run directly on USB with no battery. (The battery MUST be removed if the USB hack is applied.)
Note that the "wind" noise when I held the ozone generator up to the microphone was the ionic breeze that would normally be moving a decent amount of air through the corona discharge and out into the area being sterilised. In this product it's been encased in a badly designed product where the designer didn't really understand the operation and blocked the airflow with an unventilated recess and fine mesh.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:-
http://www.bigclive.com/coffee.htm
This also keeps the channel independent of YouTube's advertising algorithms allowing it to be a bit more dangerous and naughty.
...
https://www.youtube.com/watch?v=cvXWr8FV51s