Do you need the resistors to discharge a vector?

morphis72

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I have a rubber handle screwdriver that I have soldered a wire to with an alligator clip. It has been discharging your standard raster for me for quite some time now with no issues. Clip it to the frame, *pop* and done.

I am new to working on vectors though and have a couple (one B&W one Color) that I am trying to get working. I have read that I need to have resistors added to my setup to safely discharge or I will fry some components on the boards.

Is this true and how much resistance do I need to add?
 
Save yourself the headache and get a HV probe. The method you are using may be OK for rasters, however they put stress on HV diodes and can destroy them. And they're getting harder to find.
 
+1 for getting an HV probe. If you're rebuilding monitors, you really need one anyway, to calibrate the HV when you're done rebuilding it. The Fluke 80K-40 is the probe of choice by many folks here, and you can get them used on eBay for a reasonable price ($50-80), depending on how long you want to wait for a cheap one to pop up.

Regarding adding resistors for discharging, there are mixed opinions on this. I believe the vector monitor FAQs advocate using the resistors (which certainly isn't going to ever hurt), but there is conflicting data regarding the actual need for them. There are folks who have claimed to have discharged plenty of B/W vector monitors with a screwdriver with no problems, so YMMV.

Personally, based on the reading I've done on this topic over the years, I would say that if there is a need for resistors, it's only applicable to B/W vectors. 6100's self-discharge (which I have verified from working on many of them, and measured with a probe), and thus it's moot in that case. They also don't have an HV diode like the G05's and 19V2000's, which is the part that people claim can be damaged by the straight discharge with a straight wire.

(Note that I'm not advocating that you don't discharge a 6100, but am saying that when you do, you should get no pop, as there should be no voltage, unless something is wrong).

If you are going to build a discharge tool with resistors, the B/W vector FAQ recommends ten 100K-ohm 1/2 watt resistors in series. This is preferred over a single resistor, which runs the risk of having the HV jump across it, as HV likes to travel through air if it's high enough, and an easy enough path.
 
+1 for getting an HV probe. If you're rebuilding monitors, you really need one anyway, to calibrate the HV when you're done rebuilding it. The Fluke 80K-40 is the probe of choice by many folks here, and you can get them used on eBay for a reasonable price ($50-80), depending on how long you want to wait for a cheap one to pop up.

Regarding adding resistors for discharging, there are mixed opinions on this. I believe the vector monitor FAQs advocate using the resistors (which certainly isn't going to ever hurt), but there is conflicting data regarding the actual need for them. There are folks who have claimed to have discharged plenty of B/W vector monitors with a screwdriver with no problems, so YMMV.

Personally, based on the reading I've done on this topic over the years, I would say that if there is a need for resistors, it's only applicable to B/W vectors. 6100's self-discharge (which I have verified from working on many of them, and measured with a probe), and thus it's moot in that case. They also don't have an HV diode like the G05's and 19V2000's, which is the part that people claim can be damaged by the straight discharge with a straight wire.

(Note that I'm not advocating that you don't discharge a 6100, but am saying that when you do, you should get no pop, as there should be no voltage, unless something is wrong).

If you are going to build a discharge tool with resistors, the B/W vector FAQ recommends ten 100K-ohm 1/2 watt resistors in series. This is preferred over a single resistor, which runs the risk of having the HV jump across it, as HV likes to travel through air if it's high enough, and an easy enough path.

I ordered one for 70 bucks shipped. I figured this is my new norm so I need the right tools. Thank you very much for the answers.
 
bah... I've been working on these games since 84. Been discharging B/W vectors with a screwdriver and wire since then and have never fried one diode. I've probably had my hands on 1000's of those monitors in that time frame.

That diode is meant to handle high voltage. If your trying to discharge the tube with the monitor ON and operating then yes, you will fry the diode. Otherwise.... Go for it.

It is good to have an HV probe though.
 
bah... I've been working on these games since 84. Been discharging B/W vectors with a screwdriver and wire since then and have never fried one diode. I've probably had my hands on 1000's of those monitors in that time frame.

That diode is meant to handle high voltage. If your trying to discharge the tube with the monitor ON and operating then yes, you will fry the diode. Otherwise.... Go for it.

It is good to have an HV probe though.

I would think it would be hazardous to ones health to attempt to discharge a monitor (vector color, B&W, raster or otherwise) while it was plugged in and turned on....

Any idea how long a B&W vector will hold its charge after powering it down?
 
I would think it would be hazardous to ones health to attempt to discharge a monitor (vector color, B&W, raster or otherwise) while it was plugged in and turned on....

Any idea how long a B&W vector will hold its charge after powering it down?

He's joking. Never attempt to touch anywhere near the anode cup while the game is on. You can and most likely *will* die.

I also wouldn't just trust that using only the screwdriver+wire method is never going to fry any components. Raster seems fine but there's got to be a reason people say you can blow components on vector with that method. I mean what seems like a more sound gameplan:

1. Buying an HV probe for like $50-$80 one time and being able to safely discharge all monitors for decades to come or

2. Using a screwdriver and wire with alligator clips and taking a risk of blowing pricey components each time you discharge vector monitors... but hey, you save $50-$80... just hope nothing goes wrong for the decades to come whenever you discharge a vector monitor.

It's like health insurance. You save tons of money by not paying for it, but you're going to be in deep doody if you have a major health issue and no insurance. A person can tell you they've never paid for health insurance and they've saved thousands... and another person will tell you they never paid for health insurance, got in an accident, and had to go $50,000 in debt because of medical bills.


Take your pick.

Also to answer your other question... USUALLY most monitors will lose the majority of their charge within 1-4 weeks. But there's no magical number. You could have a monitor off for a day and it has no zap left when you discharge. You could leave another monitor off for a month and get a nasty bite from it.
 
I would think it would be hazardous to ones health to attempt to discharge a monitor (vector color, B&W, raster or otherwise) while it was plugged in and turned on....

Any idea how long a B&W vector will hold its charge after powering it down?

More like hazardous to the parts that drive HV. I did just this about a year ago. oops... I needed to rejuvinate a tube on a G07 so I discharged it and left the grounded screwdriver under the cup. Did my rejuvination, powered it back up and OH CRAP... Blew the HOT. DOH!

I would imagine and a B&W vector would hold a charge for some time. Well past a few hours I would guess. Raster monitors have been known to hold a charge for months.
 
He's joking. Never attempt to touch anywhere near the anode cup while the game is on. You can and most likely *will* die.

I also wouldn't just trust that using only the screwdriver+wire method is never going to fry any components. Raster seems fine but there's got to be a reason people say you can blow components on vector with that method. I mean what seems like a more sound gameplan:

1. Buying an HV probe for like $50-$80 one time and being able to safely discharge all monitors for decades to come or

2. Using a screwdriver and wire with alligator clips and taking a risk of blowing pricey components each time you discharge vector monitors... but hey, you save $50-$80... just hope nothing goes wrong for the decades to come whenever you discharge a vector monitor.

It's like health insurance. You save tons of money by not paying for it, but you're going to be in deep doody if you have a major health issue and no insurance. A person can tell you they've never paid for health insurance and they've saved thousands... and another person will tell you they never paid for health insurance, got in an accident, and had to go $50,000 in debt because of medical bills.


Take your pick.

Also to answer your other question... USUALLY most monitors will lose the majority of their charge within 1-4 weeks. But there's no magical number. You could have a monitor off for a day and it has no zap left when you discharge. You could leave another monitor off for a month and get a nasty bite from it.

Youre not going to "die"... Its high voltage but very low current. Will it sting, yeah it will.

Whats going to fry on a vector monitor? MAYBE the high voltage diode. MAYBE. Its what, under $10? FYI... 30+ years NEVER FRIED ONE THAT WAY.

Its overkill.
 
OK, arcadeshop is $15 but still. I've NEVER fried one by discharging a tube.

Think about the flow of electricity. Easiest path to ground. Screw driver is connected to the frame of the monitor, where is that electricity going to go. Left or right? :)
 
OK, arcadeshop is $15 but still. I've NEVER fried one by discharging a tube.

Think about the flow of electricity. Easiest path to ground. Screw driver is connected to the frame of the monitor, where is that electricity going to go. Left or right? :)

I guess it was just dumb luck but I was working on a couple deflection boards in a G05 years ago and the picture started blooming so I put a brand new HV diode in and after discharging it a couple times with a screwdriver and wire clip, it started blooming again. After that I got a High voltage probe and now discharge with it. I figure why take a chance.
 
could be. I've also had new diodes fail shortly after install only to find out that they were the wrong ones.
 
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