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|17-inch DELL Computer Monitor recyling!|
|Written by Hans Summers|
|Saturday, 01 January 2011 17:02|
Don't throw away your old computer monitor! Inside there are numerous parts to restock your junk box. Scroll down to see what useful components I found in a 17-inch DELL multisync monitor, and photographs of the dismantling process.
Take care when recycling monitors:
1) do not break the fragile glass neck of the Cathode Ray Tube
"John K" who emailed me with further warnings about dismantling monitors and televisions. CRT's can store a high voltage charge, due to their behaviour as a capacitor (metalised coating inside and outside the glass). The danger is the EHT connection which you can normally find by looking for a thick wire going to a rubbery pad on the body of the CRT. Unfortunately, even if the "capacitor" is shorted out, within minutes a charge can rebuild by itself, via a process called "dielectric hysteresis", or "dielectric soak". The electric shock one might receive would be unpleasant but would likely do less damage than the probability of then dropping the CRT, which may then implode on impact causing flying glass injuries etc. John says: "many servicemen prefer to break the exhaust pip on the tube to let the air in. Said to be safer than risking the chance of an implosion". Personally I have dismantled many TV's and monitors in my life and never suffered shock or explosion. I suppose I generally cut the thick cable, extract the CRT then leave it alone, so haven't touched the wires. Still, this warning is good advice, definitely something to be aware of. More information on the dielectric hysteresis affect can be found at: http://www.siteswithstyle.com/VoltSecond/ and http://www.faradnet.com/glossary/d_gloss.htm#da .
Inventory of useful parts
I will keep the PCB's and other parts in my junk box, and unsolder components as and when I find the need for them.
LM324 Quad Operational Amplifier (SMD)
SLA5038 5-MOSFET array
Numerous resistors, both SMD and normal, various power ratings
NOTE ALSO: Barry Smith writes: "Another part of some monitors, and most TVs, is that squarish cone of metal covering the back of the CRT. I think its a mu-metal magnetic shield. Might be worth saving. At least, that's what I tell myself."
Click the images for larger version of the photographs.
Left: If you do this on your desk at the office, people are going to ask questions...
Left: Next I removed the deflection coils. These are supposed to create a magnetic field which directs the electron beam across the face of the screen. I have seen these coil yolks before in televisions, consisting of just two coils (horizontal and vertical deflection). Not here! This one has two main coils, but all manner of auxilliary coils mounted at various angles.
Left: This small board fits in the front panel of the monitor, for user adjustment. It contains 5 buttons and one 5mm green LED.
The Sony 17-inch Trinitron tube. Destined for the rubbish dump.
|Last Updated on Saturday, 01 January 2011 17:20|