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Another Hantarex polo 25-28 repair (SOLVED)

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perjmolsen:

Hi

I got my fingers in another hantarex Polo 25-25 that I am trying to repair..
When i got the chassis the NTC and fuse where blown, NTC and Fuse replaced

- I have checked all the diodes in the PSU selection, all are OK.
- Zener diode is OK
- Checked the two large resistors they are OK.
 - T101 is OK
- HOT is OK
-Changed the large 220uf 400V cap and also C111, C112 and also the poly caps C104 and C105

- Also removed the solder at flyback pin3 and1 - and connected a  40w bulb to chassis ground. 0 V at TP6

So stepped back to TP1...there is 0V at TP1?

Where is my volts at TP1?




perjmolsen:

Found a bacd trace in the PSU section.. now i have B+ over 200V!
(with  HOT removed the solder at flyback pin3 and1 - and connected a  40w bulb to chassis ground)

Changed C112 + C114 still HIGH B+ at 200V and unable to turn it down  :dizzy:

perjmolsen:

A broken trace more in the PSU selection where the issue.
Now i can adjust it down to 145V .. but the R167 went up in smoke.. thinking that mig have been to the high B+ earlier?

perjmolsen:

Will try to check the tda1675a later today...

perjmolsen:

Put in a new tda1675a and a new C139
Now the R167 does not get hot anymore  :applaud:

Put it all together, tested my voltages they are spot on  :applaud:

TP6   145            
TP10   11.92         
TP8   26,7      
TP9   16,5      

But I have a collapsed picture, so tested
TP31 0V   

Test before R167 25V

So I got a blown  R167   (2R7)

I Think that i blew up before i changed the tda1675a (it smoked)
So I am waiting for some new 2R7 resistors... then hopefully a working chassis! :notworthy:


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