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Main => Monitor/Video Forum => Topic started by: abispac on April 02, 2020, 12:29:20 pm

Title: electrohome g07 Vertical collapse.
Post by: abispac on April 02, 2020, 12:29:20 pm
So i was trying to use my electrohome g07 which i previously broke,  so i took it to  friend and he marked  the parts that were bad in order for me to buy them and replace them , i did , now i just fired it up, and it has the infamous vertical collapse. Ive found serveral topics but most of them are way to long and most of them end up in not solving the vertical collapse. So i was wondering if theres some kind sould that would walk me trough and help me. I replaced a couple , if not most of the caps, and a small 3 leg black transistor, (not even sure if is called that) and the big round 2 leg transistor on the side, far away from the flyback, but on that one in particular , i have my doubts, as my friend marked for me, and when i was at the local supply store, i couldnt remember the numbers on the transistor so a quick google search gave me  "toshiba 2sd870", so im wondering if is the correct part to use on that particular side. So if it is, what else should i look for, if is not, whats the correct part number? thanks in advance for any help.
Title: Re: electrohome g07 Vertical collapse.
Post by: abispac on April 03, 2020, 11:49:51 am
I found the round transistor part number and hope ill get it today, ill post results later on.
Title: Re: electrohome g07 Vertical collapse.
Post by: Mike A on April 03, 2020, 12:02:35 pm
Do you have a G07 manual? There should be no mystery as to which parts to use.
Title: Re: electrohome g07 Vertical collapse.
Post by: abispac on April 03, 2020, 12:33:51 pm
Do you have a G07 manual? There should be no mystery as to which parts to use.
Yeah, i ---fouled up beyond all recognition--- on the one i bought, but after getting the manual now i know wich parts to buy, im just scared as several topics i found with the same problem, they never finish fix in it, i really would love to fix this monitor as it looks in good conditions, itas sitting on a warehouse for over 20 years or more. The chassis itself has a good condition. so i dont care if i have to change every componet , ill get it fix, but hope i dont have to change that many.
Title: Re: electrohome g07 Vertical collapse.
Post by: grantspain on April 03, 2020, 02:58:11 pm
why are you replacing the 2sd870 for a vertical fault
if you have a vertical fault the most likely issue will be one the multiple resistors that fail in the vertical circuit or the vertical transistors
Title: Re: electrohome g07 Vertical collapse.
Post by: abispac on April 03, 2020, 05:49:08 pm
Rocky mistake mr grantspain, anyway acording to this guide
http://www.pinrepair.com/g07/
Quote
The new transistor will only mount one way (unless you force it!) Do a continuity check between the outside of the transistor's metal case and the metal frame it mounts to - there should be no continuity. If there is continuity, you must replace the rubber or mica transistor insulator. If you fail to do this, you will kill the new transistor (and of course the monitor will not work).
but as soon as i add this metal holder thing,
(https://i.ibb.co/C2t42gW/11.jpg) (https://ibb.co/C2t42gW)
the ouside of the transistor gets grounded, ive seen pictures and thats the correct cable on that metal thing, so its this normal? its that the way its supposed to be? the outside can be grounded? i know the 2 pins are not. thanks for any help. i got a say i added extra plastic to make sure the transistor does not get continuity, but that metal thing gets the continuity going.
Title: Re: electrohome g07 Vertical collapse.
Post by: grantspain on April 03, 2020, 06:46:48 pm
thats the regulator transistor, it has nothing to do with vertical deflection- if that was short circuit it would blow a fuse and your b+ would be unregulated
some of the online guides are good and others are not

put it back exactly how it was before
Title: Re: electrohome g07 Vertical collapse.
Post by: behrmr on April 03, 2020, 07:24:08 pm
Many things can cause vertical collapse in a G07.  Neither of those are the large bottlecap style transistors.

Has the monitor been capped recently?  If not start there.

C402 is a little unmarked usually blue tantalum cap. This cap fails and causes collapse. 
FR401 68 ohm fusible resistor goes open or out of spec and causes collapse.
X401/X402 the vertical output transistors can go bad
Just about anything wrong in the 400's can cause collapse

Title: Re: electrohome g07 Vertical collapse.
Post by: abispac on April 03, 2020, 07:42:55 pm
thats the regulator transistor, it has nothing to do with vertical deflection- if that was short circuit it would blow a fuse and your b+ would be unregulated
some of the online guides are good and others are not

put it back exactly how it was before
I did and now my monitor is dead.
Title: Re: electrohome g07 Vertical collapse.
Post by: grantspain on April 03, 2020, 07:48:30 pm
ok show us a photo of how you have wired up the regulator
Title: Re: electrohome g07 Vertical collapse.
Post by: abispac on April 03, 2020, 09:05:24 pm
ok show us a photo of how you have wired up the regulator
(https://i.ibb.co/yRDwgVd/1.jpg) (https://ibb.co/yRDwgVd)
(https://i.ibb.co/ngp1Wby/2.jpg) (https://ibb.co/ngp1Wby)
thank you sir.
Title: Re: electrohome g07 Vertical collapse.
Post by: abispac on April 03, 2020, 09:06:38 pm
Just about anything wrong in the 400's can cause collapse
can you elaborate on what this means please?
Title: Re: electrohome g07 Vertical collapse.
Post by: behrmr on April 03, 2020, 09:27:04 pm
Just about anything wrong in the 400's can cause collapse
can you elaborate on what this means please?

Look at a G07 schematic and at the physical PCB.  You'll see parts numbered in the 400's.  Failed parts in that section is mostly where vertical collapse can happen.  Also IC501 can fail and cause all kinds of problems.
Title: Re: electrohome g07 Vertical collapse.
Post by: abispac on April 05, 2020, 11:28:35 am
i give up,took it to a pro.
Title: Re: electrohome g07 Vertical collapse.
Post by: Mike A on April 05, 2020, 11:34:05 am
Hopefully it is not the same pro who didn't finish fixing your other monitor and handed it back to you.
Title: Re: electrohome g07 Vertical collapse.
Post by: abispac on April 05, 2020, 12:49:35 pm
 :laugh2:
Hopefully it is not the same pro who didn't finish fixing your other monitor and handed it back to you.
:laugh2: