Toshiba 34hfx84

[BigTroll]

Hi i have a nice 34hfx84 toshiba tube tv, recently i broke off a rf input and bought a new switch box, my question would be does this tv automatically discharge the tube if you leave it off a day and since the small rf box is not near the tube would it be a big deal to try and repair myself, so far i have replaced caps on a few psus and never got shocked.

[BigTroll]

Re: Toshiba 34hfx84

oh heres a pic of this beauty i heard this is one of the last toshiba american made tvs before they went to orion

[RON_CET]

Re: Toshiba 34hfx84

anytime your working around the anode cap of the crt i recommend to properly discharge the Hv even after few hrs of non-operation but since your working away from the anode of the crt down near the Tuner you would not need for anode discharge

[momaka]

Re: Toshiba 34hfx84

If you're not going to remove the flyback transformer, leave the anode cap alone.

Do beware that the mains cap could still be charged, though!
Most PSUs will discharge them in just a few seconds, but keyword here is *MOST*. Some can hold the charge for days. I know because I already got bit a few times. It's not lethal but certainly dangerous if you have your hand in the TV cause you'll pull it back faster than you knew you could... and you can easily get your hand/fingers cut on something. Maybe even break the neck of the tube.

Some sets have a rail or two in the 80 to 200V range. Those can remain charged for a while as well. When in doubt, use your multimeter to check first that they are discharged.

[BigTroll]

Re: Toshiba 34hfx84

sweet,thanks for the advice guys.
i plan to at least leave it off a day, i figuere a tv built in 2004/5 should have some protection and drain the capacitors i plan on wearing rubber gloves and using only one hand, should be fine.

[retiredcaps]

Re: Toshiba 34hfx84

i plan to at least leave it off a day, i figuere a tv built in 2004/5 should have some protection and drain the capacitors i plan on wearing rubber gloves and using only one hand, should be fine.

A LG W2234S made in 2008 that I worked on recently did not automatically discharge its large filter cap. It dropped maybe 1V over a 24 hour period. I had to manually discharge it with a 100K ohm resistor.

I use a multimeter to verify always now. I use aligator clips with the multimeter so I only use one or no hands to take the reading.

[momaka]

Re: Toshiba 34hfx84

Yes, just because a TV is new doesn't mean it will self-discharge. The first time I actually got zapped by one of those large caps was on a 2007 HP LCD TV.

Checking the voltage with multimeter is a very safe way. I don't necessarily think you need to go as far as using alligator clips, though.

Also, if you have the TV unplugged, using 1 hand or 2 hands doesn't really matter much since none of the voltages inside would be enough to kill you. But they would be enough to make you pull back your hand(s) if you get zapped - and again, the danger of that is when you pull your hand(s) back, you can easily cut yourself on something.

As a final check, I do actually brush boards with the back of my hand to check if there is still anything changed. That way I'll pull my hand back from the shock if there is. Better get zapped when you're expecting it than when you're not .

If you find any large caps that still remain charged, you can discharge them with a resistor. Anything from 5 kOhms and above rated for 1W or more would do.

[retiredcaps]

Re: Toshiba 34hfx84

I don't necessarily think you need to go as far as using alligator clips, though.

It took me about 7 months to get quality probes with proper fitting aligator clips so I'm using them as much as a I can.