GE 14" Safety Question

[Electronic M]

I have done 3 of these sets. You have the early version. Chassis removal is a pain....I think I got the chassis half way out such that I could reach the HV connector on the CRT and discharged it with a probe. I have the Beitmans service manual (a reprint of GE service manual) for the late set and it reccomends crushing defective original caps and resistors on the PCBs and twisting the old and new component leads together and soldering....I have to agree with that approach....the solder side of the PCB is blocked by the chassis and unscrewing the boards to get at the solder side usually destroys the factory board standoff grounds and involves unsoldering several wires...

Originally Posted by mr_rye89

Discharging at the HV cage, whodathunk!.

On my kcs96 (chassis wrapped around the picture tube neck) it didn't matter how many times I discharged the HV lead with the long screwdriver it still managed to zap me when I reached my arm in there to unhook it from the pic tube. On that set if I take the yoke off I can get my arm in there between the chassis and pic tube neck.

HV dielectric bounce back!...It is a treacherous bitch. On almost all sets you will get it if you dead short the HV to discharge. The best way to avoid bounce back is to discharge the HV through a resistor 1M or higher....I almost always use my HV probe to discharge and never get zapped when I do....it's always when I cheat and dead short the HV (or neglect to discharge it at all) that I get shocked....

[Yamamaya42]

Originally Posted by Electronic M

I have done 3 of these sets. You have the early version. Chassis removal is a pain....I think I got the chassis half way out such that I could reach the HV connector on the CRT and discharged it with a probe. I have the Beitmans service manual (a reprint of GE service manual) for the late set and it reccomends crushing defective original caps and resistors on the PCBs and twisting the old and new component leads together and soldering....I have to agree with that approach....the solder side of the PCB is blocked by the chassis and unscrewing the boards to get at the solder side usually destroys the factory board standoff grounds and involves unsoldering several wires...



HV dielectric bounce back!...It is a treacherous bitch. On almost all sets you will get it if you dead short the HV to discharge. The best way to avoid bounce back is to discharge the HV through a resistor 1M or higher....I almost always use my HV probe to discharge and never get zapped when I do....it's always when I cheat and dead short the HV (or neglect to discharge it at all) that I get shocked....

getting shocked ( i mean by the HV) is half the fun with old sets like these!

you have not lived until POW-ZAP! your hair is standing on end!

[Electronic M]

Originally Posted by Yamamaya42

getting shocked ( i mean by the HV) is half the fun with old sets like these!

you have not lived until POW-ZAP! your hair is standing on end!

Ooh I've lived plenty...Ever seen the movie office space?...I kinda regard the HV stored in a powered off set like the protagonist regards that staticy doorknob: a necessary annoyance. I hardly even flinch in most screwups...just cus a bit.
The real scary thing to get bit off of is the yoke and the H output top cap of a powered on set...those can supply lethal current, and even if you don't get it across the chest and live to tell they will still char your skin and leave a nasty burn...I have learned that the hard way twice.

When dealing with a powered up set everyone should always keep one hand in a pocket or wear rubber gloves...

[Yamamaya42]

Originally Posted by Electronic M

Ooh I've lived plenty...Ever seen the movie office space?...I kinda regard the HV stored in a powered off set like the protagonist regards that staticy doorknob: a necessary annoyance. I hardly even flinch in most screwups...just cus a bit.
The real scary thing to get bit off of is the yoke and the H output top cap of a powered on set...those can supply lethal current, and even if you don't get it across the chest and live to tell they will still char your skin and leave a nasty burn...I have learned that the hard way twice.

When dealing with a powered up set everyone should always keep one hand in a pocket or wear rubber gloves...

I love the smell of skin burn in the afternoon, it smells like... YUCK!

I remember working on a Zenith hybrid in HS, got a little TOO CLOSE to one of the many electrified metal tabs in it that are sticking up (300v+ or so ), instant automatic reaction was to pull my arm back, this caused the tab to cut in deeper and burn a nice long line on my arm as it went. instantly cauterizing as it went.

Still have the scar.

[Electronic M]

Originally Posted by Yamamaya42

I love the smell of skin burn in the afternoon, it smells like... YUCK!

I remember working on a Zenith hybrid in HS, got a little TOO CLOSE to one of the many electrified metal tabs in it that are sticking up (300v+ or so ), instant automatic reaction was to pull my arm back, this caused the tab to cut in deeper and burn a nice long line on my arm as it went. instantly cauterizing as it went.

Still have the scar.

Ouch! That had to have been a bad day.

Burnt skin is up there with 'strand of hair lands on the soldering iron' in the least appatizing smells working on electronics department.

[old_coot88]

Ever had an RF burn from a transmitter feed line? There's no feel or sensation at all, just the wafting smell of burning hide.

[Jon1967us]

Originally Posted by old_coot88

Ever had an RF burn from a transmitter feed line? There's no feel or sensation at all, just the wafting smell of burning hide.

Negative. I haven't experienced that and I'm an Extra class ham!

[Jon1967us]

Originally Posted by Electronic M

Ooh I've lived plenty...Ever seen the movie office space?...I kinda regard the HV stored in a powered off set like the protagonist regards that staticy doorknob: a necessary annoyance. I hardly even flinch in most screwups...just cus a bit.
The real scary thing to get bit off of is the yoke and the H output top cap of a powered on set...those can supply lethal current, and even if you don't get it across the chest and live to tell they will still char your skin and leave a nasty burn...I have learned that the hard way twice.

When dealing with a powered up set everyone should always keep one hand in a pocket or wear rubber gloves...

Yeah man. I hear you loud and clear. I have a healthy respect for the dangers inherent in this hobby. There is a touch of excitement derived from "riding the lightning" that, but rest assured I have no desire to get zapped. I'm trying to do as much homework before getting started, and yes I wear rubber padded gloves, kinda like a mechanic wears, or I have the super rubber gloves.

I've been zapped already from a non discharged CRT once and that time really wasn't too bad. It just felt and sounded like discharging to a doorknob during a dry winter. I've gotten AC zaps off of transformers and chassis countless time, even once across my chest and I definitely dont want to repeat that mistake. I do the one hand in pocket thing.

[Jon1967us]

Originally Posted by Electronic M

I have done 3 of these sets. You have the early version. Chassis removal is a pain....I think I got the chassis half way out such that I could reach the HV connector on the CRT and discharged it with a probe. I have the Beitmans service manual (a reprint of GE service manual) for the late set and it reccomends crushing defective original caps and resistors on the PCBs and twisting the old and new component leads together and soldering....I have to agree with that approach....the solder side of the PCB is blocked by the chassis and unscrewing the boards to get at the solder side usually destroys the factory board standoff grounds and involves unsoldering several wires...



HV dielectric bounce back!...It is a treacherous bitch. On almost all sets you will get it if you dead short the HV to discharge. The best way to avoid bounce back is to discharge the HV through a resistor 1M or higher....I almost always use my HV probe to discharge and never get zapped when I do....it's always when I cheat and dead short the HV (or neglect to discharge it at all) that I get shocked....

I have no problem with the crushing/J-hook method. I just did some of that on my Philco. I didn't even have to take the chassis out - just worked on the IF board with the back open.

The term "dielectric bounce back" is a new one to me. I didn't know what this was called, however I was observing this phenomenon the other day with a pair of electrolytics, a voltmeter, and test clips with and without a bleed resistor, and sure enough it's the case.