Panasonic TH-42PZ85E --> Completely dead!

[Moreno83]

Re: Panasonic TH-42PZ85E --> Completely dead!

Well the off values are exactly the same as mine! When i press the power button nothing changes so im missing the 5v OUT from the PS.

What part is causing this? Can i jump a small wire from pin 12 to pin 9? I dont want to blow up the machine but fix it

[tom66]

Re: Panasonic TH-42PZ85E --> Completely dead!

For some reason your power board CPU is not turning on the output - it is detecting a fault elsewhere.

[Moreno83]

Re: Panasonic TH-42PZ85E --> Completely dead!

Ill try and measure every component on the board unless you got a better idea?

[tom66]

Re: Panasonic TH-42PZ85E --> Completely dead!

Do you have access to a scope?

[Moreno83]

Re: Panasonic TH-42PZ85E --> Completely dead!

I have 1 @ work , but the last time i used one is like 10 years ago! So i could take it home but i need help measuring.

[tom66]

Re: Panasonic TH-42PZ85E --> Completely dead!

Yes, that would be useful, get a 1X/10X probe with it, with that you can check AC_DET signal from the MC501 module.

[Moreno83]

Re: Panasonic TH-42PZ85E --> Completely dead!

I got the 1x/10x probe. Do i need a 15MHZ or 20MHZ scope?

[tom66]

Re: Panasonic TH-42PZ85E --> Completely dead!

What are the models numbers of each? If you have the choice I'd get a tek/HP/Philips/etc over a no name brand.

[Moreno83]

Re: Panasonic TH-42PZ85E --> Completely dead!

Hameg HM203 / 20 mhz
Philips PM3206 / 15 mhz

[tom66]

Re: Panasonic TH-42PZ85E --> Completely dead!

Both good scopes ... I'd get the hameg as it looks to have a line trigger which will be useful for AC_DET test.

[Moreno83]

Re: Panasonic TH-42PZ85E --> Completely dead!

Ok , i will take that one home.
The cable i have is :

10M Ohm. 15pF
10:1 , max 500VpK

[tom66]

Re: Panasonic TH-42PZ85E --> Completely dead!

Should be ok.
In the mean time I'm now on the train to work... Why not watch a few videos on scope usage when you get some free time...

[Moreno83]

Re: Panasonic TH-42PZ85E --> Completely dead!

Thx , will do that! I know the basics , but i dont know how to measure the AC_DET test.

[Moreno83]

Re: Panasonic TH-42PZ85E --> Completely dead!

Ok i took the hameg scope with me.
Nobody uses it so the signal was not that good at first. ( Some static ). Used the pot meters back and forth and the signal is now good.

Measured the 2 pins on the front ( 2v / 5v ) and it shows it correctly. I got it now setup that it shows 1v per square.
Want me to take some pictures of the power supply + settings scope?

[tom66]

Re: Panasonic TH-42PZ85E --> Completely dead!

Yes, that could be useful.

Try setting scope to LINE TRIGGER then set timebase to 10ms/div. (Trace will probably start visibly pulsating.)

Then probe the AC_DET line from the MC-module... and see what you get

Dirty pots are quite common with old Hamegs, we used to have them in school all the time.

[Moreno83]

Re: Panasonic TH-42PZ85E --> Completely dead!

I'll make some pictures first before blowing up the scope

[Moreno83]

Re: Panasonic TH-42PZ85E --> Completely dead!

This is the setup, tell me what to do in less technical english haha.

[Moreno83]

Re: Panasonic TH-42PZ85E --> Completely dead!

If i have done it right then i get 3 vertical lines on pin 13

[tom66]

Re: Panasonic TH-42PZ85E --> Completely dead!

Can you get a picture?

[Moreno83]

Re: Panasonic TH-42PZ85E --> Completely dead!

This is how i have set it up.
Picture is on pin 12/13 the same..

Do i need to ground the cable?