How to discharge High Voltage from a TV?

[Expandable]

The Vertical IC on my 7 years old JVC TV is bad and I need to replace it but High Voltage scared me from touching anything. Please help.

Aslo, if someone knows where to get the part from?

Thanks in advance.

Edit spelling.

 

[Electric Amish]

Just let it sit, unplugged, for awhile. The stored voltage will eventually leak off.

amish

 

[OutHouse]

Originally posted by: Electric Amish
Just let it sit, unplugged, for awhile. The stored voltage will eventually leak off.

amish

not entirely true. he should take it to a tv shop or electronics shop and let them dischage it the right way.

 

[Expandable]

Thanks for reply guys.

Any other advice before taking it to a repared shop?

 

[Ameesh]

Originally posted by: Citrix

Originally posted by: Electric Amish
Just let it sit, unplugged, for awhile. The stored voltage will eventually leak off.

amish

not entirely true. he should take it to a tv shop or electronics shop and let them dischage it the right way.

all the capaxciors will eventually drain out, if he waits long enough it will be fine.

 

[tweakmm]

Originally posted by: Ameesh

Originally posted by: Citrix

Originally posted by: Electric Amish
Just let it sit, unplugged, for awhile. The stored voltage will eventually leak off.

amish

not entirely true. he should take it to a tv shop or electronics shop and let them dischage it the right way.

all the capaxciors will eventually drain out, if he waits long enough it will be fine.

I wouldn't want to be the one who finds out if he waited long enough

 

[BDawg]

Originally posted by: tweakmm

Originally posted by: Ameesh

Originally posted by: Citrix

Originally posted by: Electric Amish
Just let it sit, unplugged, for awhile. The stored voltage will eventually leak off.

amish

not entirely true. he should take it to a tv shop or electronics shop and let them dischage it the right way.

all the capaxciors will eventually drain out, if he waits long enough it will be fine.

I wouldn't want to be the one who finds out if he waited long enough

Ditto. 20,000 volts, even at a low amperage would still hurt.

 

[Colt45]

20kv is just on the second anode.. theres no filter caps in that path.

(AKA the red wire from the tin box (flyback tranny) to the "suction cup")

but yeah, look out for the power supply filter caps.


have fun finding the IC though. lol

other than that, there shouldnt be much zap worthy.

(/me has taken apart 3 transistorless (all tube) TV's and a couple monitors, and im alive!)

and tubes like alot more voltage than silicon anyways

 

[BillGates]

Take a bath with it.

 

[Pliablemoose]

Don't try this @ home!!!

For the CRT, use a high wattage (not for power but to hold off the high
voltage which could jump across a tiny 1/4 watt job) resistor of a few
M ohms discharged to the chassis ground connected to the outside of the
CRT - NOT SIGNAL GROUND ON THE MAIN BOARD as you may damage sensitive
circuitry. The time constant is very short - a ms or so. However, repeat
a few times to be sure. (Using a shorting clip lead may not be a bad idea
as well while working on the equipment - there have been too many stories
of painful experiences from charge developing for whatever reasons ready
to bite when the HV lead is reconnected.) Note that if you are touching the
little board on the neck of the CRT, you may want to discharge the HV
even if you are not disconnecting the fat red wire - the focus and screen
(G2) voltages on that board are derived from the CRT HV.

 

[Eli]

Just throw some tinfoil balls in there, and shake the tv around. When the lightshow stops, you know it's safe to proceed.

 

[Expandable]

Hi all,

I did found the IC and able to get the part too. I did research on google news groups and it appears that it is a common problem for JVC TVs (The picture shrink to a bright horizontal line on the screen; tap on the Vertical ICs and picture become normal). It may be just a broken joint. Don't you guys think It is risky if I just resolder the joint without touching anything else and not to discharge HV? Also discharging High Voltage by shorting the big red wire (look like a sparkplug wire on a car) to the CRT coverd by a "suction cup" to ground (TV frame)?

Thanks.

 

[cressida]

t'was testing something.

 

[NogginBoink]

Obviously the IC won't be part of the high voltage area. You should be able to solder it in relative safety if you stay away from other areas.

OTOH, discharging that fat red wire to ground would increase the safety while soldering. That, of course, brings up your safety while discharging. Be careful and you should be fine. Clip alligator leads from ground to a screwdriver and slide the screwdriver under the suction cup, keeping one hand behind your back.

 

[Expandable]

Thanks for the advice. I think I gonna do it myself without taking it to the shop.

 

[Jugernot]

Lick it....

 

[kherman]

Originally posted by: Eli
Just throw some tinfoil balls in there, and shake the tv around. When the lightshow stops, you know it's safe to proceed.

I've done this before, it works!

 

[Linflas]

Back in the tube days the common way to discharge them was a very large screwdriver across the chassis and the contact for the diode tube in the flyback transformer. Here is a link to how to do it safely. Safety for high voltage equipment.

 

[Expandable]

Thanks for the link Linflas.

 

[Yossarian451]

I learned either you used a screwdriver with a plastic handle or take a pvc tube and put a nail at the end, and bridge the capacitors. Get the big ones and you shold be pretty safe, just don't worry about small shocks, they don't really hurt as much as 120v straight, long story about vcr repair and why the one hand rule is important. Which reminds me, use the one hand rule, use only one hand to touch stuff at a time.