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hantarex polo 28 blows fuse
perjmolsen:
OK thanks Grant :cheers:
I have changed all the caps in the PSU selection again.. still the same
:dizzy: testing components.... still not have figured out why the psu shutting down when i attach at 40W bulb to pad on pin3 at flyback. (solder removed at flyback pin3)
It must be in the PSU selection...
In my test i have removed one leg at
D112
D117
D118
D119
Only D116 is connected - and i have also changed the diode just to rule that out.
My multimeter is connected to TP6 and its pulsing. :badmood: :badmood: :badmood:
Can it really be this time i have to give up---?!?
Resistors R111,R112,R113 is also tested ok..
What do I overlook.... :banghead:
perjmolsen:
Some pictures of the back and front at the psu on the chassis
perjmolsen:
Update..
I have now found out why i had pulsing volts. :applaud:
It where the D105 that had gone bad again!!!...so swapped it out with a new one.
Had still removed one leg on
D112
D117
D118
D119
Also removed solder at pin3 flyback
Only D116 is connected to rule out the rest of the board.
40W Bulb connected to pad before L103
Test leads to multimeter connected to D116 + at the end with the stripe on the diode and - to chassis
Turned it on an.. power at my bulb for a short time them something shorted/burned around D116.
I have tested the resistors R129,.R130, R131, C123 around the diode, also the small ceramic discs all seems fine.
Also D115 is fine.
So now i need to figure out what burned.. and why it burned... up hill but i am not giving up yet :o
perjmolsen:
Connected all again
D112
D117
D118
D119
Moved 40W bulb to pad on leg 3 at flyback
Tested T101 - OK
IC101 - OK
Put in a new C121 100uf 450V and now back to pulsing volts with 40W bulb connected.. 4-5V
without bulb connected 100V
... so back to where i started
perjmolsen:
Update..
Checked comonents one more time...
T114 - HOT - OK
D116 - OK
D117- OK
D118- OK
D119 - OK
D134 - OK
D135 - OK
C172 - OK
C174 - OK
C175 - reads 12nf - replaced with a new 22 nf poly
C114 - OK
C112 - OK
R130 - reads 4.40 ohm according to manual it must be 3.9 Ohm
I only have a 3.3ohm - reads as 3.5 ohm - can i replace R130 with that one?
The R130 is around that place where i yesterday saw some smoke, so it must has been R130 who blew up..