5 boards to have a crack at

heres a short vid

(you have to click 'display dodgy content' at bottom of screen for vid to appear)

the ue8 I am using was from a dead machine - are all these chips the same or is there different versions of a UE8 chip or does the big chunk of UE8 that I knocked off kinda upset the whole show?

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cleaned ron and ram simms (I have 4 in it) with a rubber. Reseated the video memory chip

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I removed UD8 during the cleaning to make sure the torn traces were not touching under the UD8.............they were not. When I went to put it back there was no writing on the chip to orientate it.......so I think I put it back the right way

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helllppppppppppp

I dont see the video?? 

Nevermind, I just went to your channel and looked at the last uploaded video. Simple enough. 

You would be better off replacing those chips with new. I have a stash I ordered from digikey to do it. They are all the same. Well sorta. 

There are HC, HCT, AS, F, variants, all with different speeds and voltage ratings. But otherwise thats about it. 

In your neck of the woods, maybe Farnell carries them. 

don't know why my vids only show when you click on 'show all content' on the bottom of the screen techknight.

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I have metered out all the connections and they are not shorting. they are all the same as the good board. But I am not using the schematic.

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you say replace those chips.... as in all the video chips UA8 up to UG8...as in all 7 of them

I have another dead se30 ( I have 3 in total) and the ue8 has the numbers tif022 cr   ls166a. All 7 are there... as in 1 set.

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change them all?

No... You want to replace UE8 with a brand new one, trust me. 

With the horizontal line cutting in and out is a for sure bad connection, But replacing UE8 with a brand spanking new SN74LS166 would remove this factor out of the equation, so you dont have to keep mucking with it. 

we wouldn't have anything like that in Ireland techknight.

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believe me this is one crap country for getting specific stuff. Everything is got online. So is a SN74LS166 some kind of generic chip that will definitely work as a UE8

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been at this dam thing 4 hours now so feck it im off to bed. Gigging for the weekend so will have a stab at it on monday

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cheers peoplez

A question.

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can an se/30 "single horizontal line" be caused by just UE8.?..........or can it be cause by any of the Ux8 chips (7 of them I think).....or anything else??

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Display is perfect when I install my good board.

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I have  worked on the Ux8 chips, replaces the the FUJ2 258 chip, replaced both transistors next battery and crystal next battery - those parts were missing

Im running out of options

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cheers people

Swap the PALs with a known good board? 

what are the PALS....the ux8 chips?.............jasus ...im sure you told me before!!!!!

All the socketed chips nearby. Out of all the SE/30 boards I had rebuilt, I have seen ONE case where the PAL/GALs were bad. it was causing the analog board to scream bloody murder. Replaced em, came back to life. 

jesus - great bleedn idea thechknight

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will have a look

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cheers man

heres what I did tonight - took off UE8 and UC8 ( to find the via for one of the pins) - this exposed all the first via's , along the trace , to all the missing pads left

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got smaller wire

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finished it up ( no picture, time!) - but its still the same

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will put up more pics tomorow

Techknight - went to swap out the PALS only to find they are all soldered into the board. Swapped out the video rom - still no joy.

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heres where it is at now.

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Id better get this going soon because the more I go at it the weaker all the connections, pads, traces are getting.

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I have metered out the UE8 with my good board and it checks out...cleaned the boards both sides........I just cant find the fault...........it has to be something stupid.

somebody gave this description in another post of same problem

"the Vertical Sweep IC at U2 (TDA1170A, 12-pin)"

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what chip is that?..........I cant see a 12 pin chip on the se/30 board anywhere!............is this chip on the analog board?

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I have metered out all the Ux8 chips and compared them to a good board. EVERY PIN IS CORRECT

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is there anything else that's would cause the horizontal line.

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would it be worth metering out all the pals

Isn't that U2 on The analog board?

thanks 360alaska.

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the analog board is good. When I swap in my good board display is perfect..............so its this darn motherboard.

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I just cant find the problem and I cant hot air gun chips off anymore, the pads will all come off if I keep swapping chips

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have to go on the assumption the chips are good

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ah well..........off to a gig..........will spend hours staring at this thing later

yep - you are right - I just read the rest of the post where I heard about the U2 and indeed he was referring to the analog board

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my bad

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its desperation at this stage

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weh hey!

Well you need to look at the schematic. where is the vertical signal generated? the PALs I believe. 

Even though they are soldered on, I would replace the one that is directly responsible for generating the vertical sweep drive. 

Messing with UD8/UC8, etc all day isnt going to fix this problem I dont believe. 

falen5 said:

yep - you are right - I just read the rest of the post where I heard about the U2 and indeed he was referring to the analog board

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my bad

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its desperation at this stage

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weh hey!

Click to expand...

Alot of those suggestions come from here: http://www.biwa.ne.jp/~shamada/fullmac/repairEng.html

But of course, you know you analog board is good... Unless that board has a short somewhere that damaged U2, Unlikely though...

thanks for all you help people.

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looks like I will have to do a crash course on reading schematics and on how to use them.

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until I do I am probally wasteing peoples time.

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anybody got any links to any good tutorials on utube

http://museum.dyne.org/gallery/apple/stuff/mac/andreas.kann/schemat.html

maybe this graphic i made will help you?  

thanks uni - I looked at the drawing and understood nothing............then again im drunk as a lord - weh hey!

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to be honest ive got to the stage where I must understand what is actually going on  , on the board - what ALL the chips do etc etc

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this is becoming an obsession.......just have to understand the board logic, use it to understand a problem, and again use it to find and fix the bas%$£d of a problem

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It kills me not having the knowledge I need to understand this

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off to utube for tutorials............god help me

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thanks again all

techknight - totally agree with you there

Update.......

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Success ...........

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blank video. 

try again techknight...... its processing 1,3 gig of dv fottage..........will work when done

good job!!! u is the man!

It looks like now the SWIM chip has problems, or the floppy drive is bad? It keeps flashing an X on the disk icon on the boot screen.

if you keep watching though, he disconnects the HD,  and then it becomes a ? mark… he did say in the video his hd was bad.     and he did boot it up from a floppy disk and it works.