G07 CBO Smoked a New Flyback... I need some pointers. (FIXED!)

TSB

Well-known member
Joined
Jan 14, 2016
Messages
2,541
Reaction score
916
Location
Alaska
G07 CBO Smoked a New Flyback... I need some pointers. (FIXED!)

I worked on this G07 a while back, but didn't have all the parts, so it sat. I put in a New Flyback and New Caps, but it also needed a new HOT and F901 Fuse (and maybe a Width Coil).

Skip forward to today: I finally got around to putting in the HOT, Fuse, and R908 that BR suggests. I also went around and hit the solder points of everything that I had replaced a while back, double-checking and cleaning along the way.

I powered it on and Smoke slowly spewed from beneath the Flyback Transformer.

Where should I start troubleshooting next? I can't find reference to a flyback letting the smoke out after replacing all those parts...
 

Attachments

  • IMG_2754.JPG
    IMG_2754.JPG
    182 KB · Views: 64
  • IMG_2753.JPG
    IMG_2753.JPG
    144.1 KB · Views: 57
  • IMG_2756.JPG
    IMG_2756.JPG
    366.8 KB · Views: 69
Last edited:
Where'd you grab that flyback, the unit itself could be a dud. I recommend security0001 never had any issues. Based on the caps I'd say yours is bobroberts but I don't know.
 
Does that happen? My first thoughts were along the lines of another part frying the original - then frying the new one.

Where'd you grab that flyback, the unit itself could be a dud. I recommend security0001 never had any issues. Based on the caps I'd say yours is bobroberts but I don't know.
 
look for cracks in the chassis around the flyback.

they can crack and break then ark and cause smoke when it burns any residue on the chassis.

make sure the area is clean and no cap legs were stuck in places they should not be.

i also stock flybacks if you need any parts, click on my store link below in my sig.

if you hit a brick wall and need it repaired, your welcome to send it in.

Peace
Buffett
 
I'll take off the flyback and look for cracks on the board. The smoke came from between the board and the flyback, so that could be a possibility.

The caps/flyback came from arcadeshop and all have clean connections to the board.

look for cracks in the chassis around the flyback.

they can crack and break then ark and cause smoke when it burns any residue on the chassis.

make sure the area is clean and no cap legs were stuck in places they should not be.
 
I worked on this G07 a while back, but didn't have all the parts, so it sat. I put in a New Flyback and New Caps, but it also needed a new HOT and F901 Fuse (and maybe a Width Coil).

Skip forward to today: I finally got around to putting in the HOT, Fuse, and R908 that BR suggests. I also went around and hit the solder points of everything that I had replaced a while back, double-checking and cleaning along the way.

I powered it on and Smoke slowly spewed from beneath the Flyback Transformer.

Where should I start troubleshooting next? I can't find reference to a flyback letting the smoke out after replacing all those parts...

that hot is fake because toshiba didn't use that style of case with red writing. make sure the flyback is seated tight to the pcb and you have good solder connections. if all that is correct pull the flyback and lets see a picture of the underside. flybacks can crap out new and if you got unlucky with a turd see if who you purchased it from will warranty it. i do all mine and i stock many thousands of flybacks. let me know if you need anything as i am happy to help.
 
That is a clean looking chassis.

I guess I need to reread your first post. I assume there is no image on your screen? What is the b+ measurement? Is either fuse blown?

Yes , security0001 should be your go-to for monitor parts in my opinion. He will stand behind his products if something is bad out of the box.

Contrary to br's claims, user error is only relevant in blowing flybacks about .00001 of 1% of the time.
 
I have a habit of watching the boards for a few minutes after I plug them in, so I don't know if it ever had an image on it. On the other hand, I was able to unplug it as soon as the smoke started, so I may have saved the board from a crispy death.

Neither fuse popped, it was almost as if the power was ramping up - leading me to initially think that there was another part malfunctioning.

I don't have a way of testing C904, is there another B+ part to check?

That is a clean looking chassis.

I guess I need to reread your first post. I assume there is no image on your screen? What is the b+ measurement? Is either fuse blown?

Yes , security0001 should be your go-to for monitor parts in my opinion. He will stand behind his products if something is bad out of the box.

Contrary to br's claims, user error is only relevant in blowing flybacks about .00001 of 1% of the time.
 
Pics of the board and Flyback. The smoke must have been coming from the edge of the Flyback, not underneath... or maybe the through-holes? I couldn't see anything indicating smoke from the Flyback itself.

I'm baffled as to where this smoke was emanating from because it was engulfing the base of the Flyback.


that hot is fake because toshiba didn't use that style of case with red writing. make sure the flyback is seated tight to the pcb and you have good solder connections. if all that is correct pull the flyback and lets see a picture of the underside. flybacks can crap out new and if you got unlucky with a turd see if who you purchased it from will warranty it. i do all mine and i stock many thousands of flybacks. let me know if you need anything as i am happy to help.
 

Attachments

  • IMG_2771.JPG
    IMG_2771.JPG
    164.5 KB · Views: 69
  • IMG_2772.JPG
    IMG_2772.JPG
    131.3 KB · Views: 62
I cleaned up the contacts and some of them lifted off and fell apart. I was hoping that I'd found where the burning came from, so I put it all back together with some "elevated pads" (wire doughnuts).

No such luck. The monitor warmed up and smoked again, this time it left a black mark on the white focus wire just above the board. Maybe something next to the Flyback?

Pics of the Flyback (solder side):
 

Attachments

  • IMG_2787.JPG
    IMG_2787.JPG
    202.2 KB · Views: 47
  • IMG_2786.JPG
    IMG_2786.JPG
    237.6 KB · Views: 47
  • IMG_2785.JPG
    IMG_2785.JPG
    212 KB · Views: 43
Found It!!! D503 was roasting.

I haven't read anywhere about people having issues with that diode, nor can I find a replacement referenced for it.

The description is "Si. Diode" with the part# "HF-1". Anyone know of a replacement (or specs of the diode)?
 

Attachments

  • FullSizeRender 64.jpg
    FullSizeRender 64.jpg
    153.4 KB · Views: 116
  • g07_schematic.jpg
    g07_schematic.jpg
    415.4 KB · Views: 35
  • Screen Shot 2017-06-02 at 7.53.41 PM.png
    Screen Shot 2017-06-02 at 7.53.41 PM.png
    17 KB · Views: 24
huh, the manual lists a part #, but I am less experienced than some at deciphering it.

Let me check my parts chassis, maybe I still have it on there.
 
behrmr, I used your suggestion to trace back the "equivalent replacement" list over the years
until I was able to find an old document with the HF1 specifications.

I'll post a screen grab for future reference, see line #17.

Thanks for all your help everyone! I'll get this thing running eventually!


Thanks!
Does it need to be Fast Recovery?
Or will a 1500V 500mA Standard Recovery do?
 

Attachments

  • Screen Shot 2017-06-02 at 11.49.39 PM.jpg
    Screen Shot 2017-06-02 at 11.49.39 PM.jpg
    299.5 KB · Views: 42
Last edited:
I'd grab a few of them incase something is causing them to smoke up just to be sure.
 
Found It!!! D503 was roasting.

I haven't read anywhere about people having issues with that diode, nor can I find a replacement referenced for it.

The description is "Si. Diode" with the part# "HF-1". Anyone know of a replacement (or specs of the diode)?

I had one of those explode in my face after a rebuild, lucky for me I had my glasses on!
 
Back
Top Bottom