Panasonic TH-P50X60b Seven Blink.

[diif]

Re: Panasonic TH-P50X60b Seven Blink.

What is the silicone for on the buffer ICs, do you replace the silicone if you replace an IC ?

[ReeceyBurger123]

Re: Panasonic TH-P50X60b Seven Blink.

Just some photos showing after a 5min with the silicone remover and a clean you are ready to cut the pins and remove the ICs , I do not use hot air just low melt solder that I get of ebay for about £7.00 for 1m that lasts forever.and for sealing up when the new IC is fitted I use Permatex ultra grey made in the US and was recommended to me by a Panasonic repairer tech. hope this is of some help to you

Sweet Flocko thanks for that

[Alastair E]

Re: Panasonic TH-P50X60b Seven Blink.

What is the silicone for on the buffer ICs, do you replace the silicone if you replace an IC ?

Its to prevent tracking etc from moisture and dust/crud build-up on the pins...

Cant see the point of Silicone at all. All that's needed is a coat of coil-varnish like Ulti-Meg.

--The Tracks on the board have only the solder-resist doing exactly the same between the tracks, so just Why silicone is used is anyone's guess.

Guys get SO hung up on using silicone and all sorts--when there's Really NO need at all.
A coat of std Polyurethane would prob be OK too, but I prefer the Ulti-Meg as its very quick drying and completely effective....

Ive seen some early plasmas with nothing at all on the pins--but the pitch of them was coarser, so distance greater...

[flocko]

Re: Panasonic TH-P50X60b Seven Blink.

Let me make my point why you should be using silicone, it removes moisture that would be left around the pins of the IC (this is what makes it cure) that is picked up in the humid air that we live in, and also stops it returning by sealing it out after it has cured. Hot glue and Ulti-Meg will not do this, they have there uses but not for this job.

[Alastair E]

Re: Panasonic TH-P50X60b Seven Blink.

Nah--I'll leave the silicone for you guys. I am happy with Ulti-Meg, never had an issue and been using it for some years, takes less than 15 mins to dry, and during this time creeps through, under, between the pins and the base of the chip Sealing it properly, Unlike all the messy stinking silicones around, that you'll just spread over the pins, nothing underneath or under the chip......

Ulti-Meg will seal the pins/tracks better IMO than mearly spreading silicone over the chip pins--What stops the moisture creeping up via the Vias Under the chip to infect the pins Under the silicone?--Nothing!

--Silicone, Hate the stuff--Leave it for Engine re-assembly, has no place in TV repairs IMHO.......

If you've just used Hot Air to remove the old one, (lets face it they really Have to be hot-aired off, the board has been to around 230 deg C so NO moisture will be there)--Then used soldering to fit the new one--There'll be no moisture there worth mentioning Anyway!!
Coat or two of Ulti-Meg and that's all sealed up, Job Done.

Silicone--The Wrong one would be disastrous as it liberates Acetic Acid that rots out the copper tracks or the buffer-chip pins--Also, Acetic acid is conductive....

The Right One takes around 5 days to properly cure, and I'm sure due to the liberation of Alcohol due to curing would still be slightly conductive--Till fully cured--3-7 days later.
Dunno bout you--But I ain't got 7 days to keep a set held up while the silicone cures!

Hot-Melt glue is another good alternative but not used it myself, That stuff is pretty hot, would dry out the board on application--IF it still had moisture--if it had been left open for some hours before sealing.

[flocko]

Re: Panasonic TH-P50X60b Seven Blink.

So Panasonic have got it all wrong then? and would be better of using something that has been around like me from the late 40s, I was using Uti-Meg on motor rewinds when i was a boy. Not seen or heard of it for years.messy old shit but each to there own as you say

[ReeceyBurger123]

Re: Panasonic TH-P50X60b Seven Blink.

Or you could be me and use hot glue like most sammy and Lg use lol

[Alastair E]

Re: Panasonic TH-P50X60b Seven Blink.

So Panasonic have got it all wrong then? and would be better of using something that has been around like me from the late 40s, I was using Uti-Meg on motor rewinds when i was a boy. Not seen or heard of it for years.messy old shit but each to there own as you say

TBH--Yes, I think Panasonic HAVE got it wrong! Wouldn't be the first time a Maker--Even a Huge Co--Got It Wrong! They got it wrong in the design of TNPA5081/5105 IMHO otherwise they Wouldn't Blow Up in the first place!

--They Don't Use Silicone either--but some kind of Grey/Black Mastic Crap--a hard plastic tarry rubber...

They (Panasonic et-al) never really intended these boards to be repaired anyway, Or they wouldn't use that crap on the pins of chips that do fail now and then, making them extremely difficult to remove without track/board damage--Thats why the manuals always just say, Change Board SU/SD/SN etc....

I think that the modern 'Ulti-Meg' is probably different from that used in the 40's. There's many different grades of it too....

[flocko]

Re: Panasonic TH-P50X60b Seven Blink.

I was asked what I use and how I do Panasonic buffer repairs, and I have told you . If you think you have a better method and it works for you that is fine, you do it your way I will do it mine, and you could be right that Ultimeg has moved on with different products in the last 50/60 years I would not know.but I do know my trade customers would not be best pleased to see refurbished Panasonic boards sent out with hot glue or polyurethane paint on the buffers

[Alastair E]

Re: Panasonic TH-P50X60b Seven Blink.

Here you go,--

http://www.aev.co.uk/aev_ultimeg_2000.php

You'll be interested to see they do Silicones too....
--They do so many Different sealers, coatings, tropicalisers and potters to keep Anyone happy!

Ulti-Meg --aint just varnish!

Been around making this sorta stuff since 1849, so must be reasonable or they would have gone long ago...

[sordids999]

Re: Panasonic TH-P50X60b Seven Blink.

Sordids sent me a lot Panasonic boards TNPA5335 and buffers from a set with a broken screen am waiting for buffer ICs but the SN tests fine

Omg now my name has popped up

[Alastair E]

Re: Panasonic TH-P50X60b Seven Blink.

Haha--You didnt think we would leave you out did ya buddy....?

[flocko]

Re: Panasonic TH-P50X60b Seven Blink.

Alastair so what one are you using ? please share

[michael dranfield]

Re: Panasonic TH-P50X60b Seven Blink.

Not sure why you have to take the sillicon off first ????

Heres one I have just done and left the silicone on , its much easier to remove from the board with the chip off first.

[michael dranfield]

Re: Panasonic TH-P50X60b Seven Blink.

Here is the board after cleaning , no need to worry about the silicone burning , it has a very high temperature rating , I use it on my van to seal the exhaust , its much cheaper than exhaust putty !