WTB: monitor discharge tool

pookdolie

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I don't want to make my own. I want something professionally made, slick, fool-proof, and ideally with some sort of voltage indicator on it to let me know when the monitor has been fully discharged.

I remember hearing about a tool like this being available, but I can't find any information now...
 
Screwdriver, jumpercables. Ill make you one?

+1

I doubt there is anything 'professionally' available - we were taught during my apprentiship to use a clip lead and a flat blade screwdriver. The voltage won't kill you anyway - just give you a fright.

ALWAYS clip the first end of the cliplead to the frame or earth braid of the tube FIRST - then attach it firmly to the shaft of a thin flatblade driver. Holding the INSULATED handle slide the blade under the rubber anode cap (ultor cap to be exact) and you will hear "CRACK" as the tube discharges. Using the screwdriver, carefully lever the edge of the cap up so you can see the actual connection on the tube and hold the end of the driver on it for a couple of seconds to ensure full discharge.

NEVER run you fingers or hand near this connection when handling a tube as there can be a small residiual charge - enough to frighten you and possibly cause you to drop the tube.

Do I really need to say "make sure the unit is turned off and unplugged BEFORE attempting this"
 
I have one of these (either the craftsman or snap-on version from working on cars), tho i'm not brave enough to do a tube discharge myself, wouldn't this work? (and show if there's residual voltage by the light inside being on/off?)
 

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I have one of these (either the craftsman or snap-on version from working on cars), tho i'm not brave enough to do a tube discharge myself, wouldn't this work? (and show if there's residual voltage by the light inside being on/off?)

NO - that tool is for 24V max - tubes hold 15,000 to 28,000 Volts !!!!

You just don't need anything more than a flatblade screwdriver with a good plastic handle and a cliplead - and, I nearly forgot - some COMMON SENSE!
 
Theres really nothing to this. Connect a low impedance path from the CRT tube anode to chassis ground.

Just be aware that the TUBE is the part that holds the charge, not the chassis. The chassis may have a cap that has a charge.

Theres nothing to buy just make one out of a good handled flatblade and some wire stripped on both ends. wrap one end around screwdriver. connect other to chassis ground. Done!

You will know when it discharged, it will sound like a light bulb blew.

The tube will generate static electricity after being discharged by the screwgie, so be sure to ground out the Tube every time you handle it.
 
good to know about that tool being 24v max, i had a buddy who owned a local arcade replace mine and yea he used a screwdriver and either gator clip jumpers or something more Mcguyver like. That automotive tool is just the first thing that came to mind when thinking of something Mass Produced. the one i have is much much more heavy duty than that klein one but as stated i'll never do it. but if i ever do i'll remember this discussion lol.
 
I have one of these (either the craftsman or snap-on version from working on cars), tho i'm not brave enough to do a tube discharge myself, wouldn't this work? (and show if there's residual voltage by the light inside being on/off?)

using that test light, the high voltsage will just blow the bulb.

Now if you took the bulb bot and shorted that area so it was a straight connection, yeah i suppose that would work.


ive also used dmm leads in a pinch ******NOT RECCOMENDED*******
 
I call that what it is - a high voltage probe - it will MEASURE any voltage present but it will not discharge the voltage.






you sure about that :D

alot of vector guys use a hv probe to discharge because using the old screwdriver and wire trick will actually blow some diodes on the chassis.

Using a hv probe works, but it takes alot longer then "instantly" to discharge

I have heard of guys using resistors in series on the wire between a screwdriver and ground to also provide a safer slow discharge of the tube, but i cant tell you an exact value resistor(s) you would need
 
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WoW that Mame nut is busy :eek:

The screwdriver with a wire and an alligator clip works just fine for most monitors.
A Hi Voltage probe will also discharge the tube more like a bleed off rather than all at once.
Many people want to argue the point but DO NOT discharge a G05 black and white monitor like found in Asteroids, Lunar Lander, Red Baron. Battle zone ETC. directly with the screwdriver and ground clip. It will cause the diode stick go bad and they are getting harder to find. It even states this in the Black & White Vector Monitor FAQ and Guide.
You should NEVER short the anode of the tube DIRECTLY to common ground. ALWAYS use a
resistance of 1 Meg ohm between the anode (underneath the suction cup) and common ground. A
direct short without the resistor(s) will cause the HV Rectifier Diode (D903/D904) to fail. Ten
100K-Ohm ½ watt resistors in series is the best method. You could use a single 1 Meg ohm, 3W
resistor, but the problem is flash over failure. Using a single resistor that is dropping 20KV instead
of 10 resistors that are dropping 2KV each increases the likelihood that the single resistor will short
out and provide no protection for the HV Rectifier Diode. Make sure the resistors are sheathed in
some heat shrink tubing for protection.
I would strongly recommend using a High Voltage Probe to discharge the monitor. This is the
safest method, as the probe is designed to withstand extremely high voltages
 
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