CRT Monitor Discharge

[Jesfa]

Been browsing the forums a good bit since I picked up a cabinet on the cheap that I wanted to convert to a multi-arcade.  Learned a lot from posts on here/working on it, and can't wait to try again and do it better next time since I've made some mistakes this first time around.

That being said, I'm on my last stage of the job (Other than decals/painting/cosmetics), and I'm attempting to replace the old 19 inch arcade monitor in my cabinet, with a 19 inch CRT tv.  With the plastic shell off the "new" tv going into the cabinet, the two tubes look nigh identical, and it fits 100% perfectly into the monitor frame which is a huge plus.  My only issue I have is that having done not nearly enough research on the issue until I was partway through, I didn't realize the monitors carry a charge even when unplugged.  I pulled the frame and monitor out of the cabinet, and removed the frame from the monitor on my dining room table, and then removed the plastic shell from the replacement tv before I discovered you need to discharge before safely working on these, so I promptly stopped and thanked my stars I didn't shock myself at all.

I've watched a number of videos on youtube/google searching, spoke to an electrician friend, and am supposed to call an arcade repair guy I met at a local arcade later this week; but I thought I'd get some input here first to see what you guys would do/how you do it.

My "plan" is to use car jumper cables, attaching one end to a screwdriver, the other to the metal frame that previously held the monitor (as a ground).  Then wearing some fairly thick rubber glove, probing the screwdriver under the suction cup to discharge.  Having little experience myself, this appears to be the exact same thing I've seen in a few videos, but they're never the EXACT same procedure in all the videos, so I thought I'd pitch it here and see if you had any thoughts.

Thanks guys!

[yamatetsu]

You might want to check the 'The Monitor FAQ' sticky in the Monitor/Video Forum. Discharging the monitor is decribed in the second post.

[Jesfa]

Ah!  Read the first post and several of the others, missed the bottom bit of post #2!

Likely going to buy alligator clips later this week then, though I imagine car jumper cables would do the exact same thing. Thanks!

[behrmr]

Please don't toss the original monitor chassis.  If it's a common model give it to a collector.  I may be interested in it depending on the model.   

Discharging doesn't require jumper cables or rubber gloves or a hazmat suit or a tinfoil hat or crocks or condoms.  Grab a screwdriver and attach a jumper to the shaft of the screwdriver and the frame of the monitor.  If you don't have a jumper grab any length of wire strip a couple of inches and wrap it around the shaft and secure it with electrical tape. Do same with the other side and attach to monitor frame.  With one hand holding the screwdriver (do whatever you want with the other hand as long as you're not grabbing anything on the monitor. Wave to your neighbor or something if you feel the need) slide the blade under the anode cup and contact the metal cup.  You may or may not hear a snap depending on the type of monitor.  I do this all of the time and I use a cheap jumper wire with alligator clips and a pocket sized  screwdriver.

[pbj]

You're gonna die.  Don't even attempt it.

[AndyWarne]

There is no need at all to discharge the CRT unless you are planning to separate the CRT from the base board. If simply handling the monitor as an assembly, even uncased, the CRT stored voltage is not present on any external component.

On the other hand, there are power supply capacitors which are accessible and dont get discharged even if you did discharge the CRT, but these will decay after 15 mins or so.

[Jesfa]

There is no need at all to discharge the CRT unless you are planning to separate the CRT from the base board. If simply handling the monitor as an assembly, even uncased, the CRT stored voltage is not present on any external component.

On the other hand, there are power supply capacitors which are accessible and dont get discharged even if you did discharge the CRT, but these will decay after 15 mins or so.

I was trying to find out exactly whether or not I actually needed to discharge the CRT in order to move it to the frame; but all my searches kept resulting in how-to guides.  Never could find the if/when you need to.

[Jesfa]

Please don't toss the original monitor chassis.  If it's a common model give it to a collector.  I may be interested in it depending on the model.   

Discharging doesn't require jumper cables or rubber gloves or a hazmat suit or a tinfoil hat or crocks or condoms.  Grab a screwdriver and attach a jumper to the shaft of the screwdriver and the frame of the monitor.  If you don't have a jumper grab any length of wire strip a couple of inches and wrap it around the shaft and secure it with electrical tape. Do same with the other side and attach to monitor frame.  With one hand holding the screwdriver (do whatever you want with the other hand as long as you're not grabbing anything on the monitor. Wave to your neighbor or something if you feel the need) slide the blade under the anode cup and contact the metal cup.  You may or may not hear a snap depending on the type of monitor.  I do this all of the time and I use a cheap jumper wire with alligator clips and a pocket sized  screwdriver.

The original monitor is in working shape, though I think there's a very  faint image burn of "Lotto Fun II".  Haven't turned it on in a couple months, but I think I remember that.

[jtslade]

Why would you not just use the Arcade CRT?

Andy makes an Arcade VGA..

GroovyMame / Arcade will run with CRTEMU drivers / Atom 15


I did Svideo TV for many years and will never go back.

[behrmr]

There is no need at all to discharge the CRT unless you are planning to separate the CRT from the base board. If simply handling the monitor as an assembly, even uncased, the CRT stored voltage is not present on any external component.

On the other hand, there are power supply capacitors which are accessible and dont get discharged even if you did discharge the CRT, but these will decay after 15 mins or so.

I was trying to find out exactly whether or not I actually needed to discharge the CRT in order to move it to the frame; but all my searches kept resulting in how-to guides.  Never could find the if/when you need to.

Yes. You should discharge it to remove it from the frame.  Basically if you need to remove the HV anode wire (cup thingy) from the tube then you need to discharge the tube first.

[Jesfa]

So after all my concerns, the monitors either had no charge left in them, or at least when I discharged them there was no audible or visible indication that they had discharged.  Pulled off the anodes on both without a hitch; thanks guys.

@jtslade:  I was originally going to try and use the original, but didn't find much in the way of how to connect it to a Pi.  Several articles I read had how-to's that involved some soldering and such, but wasn't very comfortable trying that.