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Hantarex Polo/2 25-28 Dead - how to test B+ (SOLVED)
perjmolsen:
Hi
I got this Hantarex Polo/2 25-28 that is dead, so I am trying to repair it.
I have successful repair Hantarex Polo's, but newer a Polo/2, so I need some basic help with this one.
There is no ticking sound, completly dead.
I have tested the fuse, that is good.
Testtet OL from HOT middle leg to chassis.
I have no schematic for Hantarex Polo2, and it does not seem that the normal testpoints as in the Polo are present.
1. How do I connect the 40W bulb to test the B+ power supply? What do I need to lift?
2. Where do I test the normal volts? and what should they read?
3. If my PSU volts are OK, can I still de-solder leg3 on flyback to see if it the flyback is dead
perjmolsen:
It seems tthat the PSU is putting out power
R32 = 23V
L6 = 15V
Tested the diodes after the PSU:
D6
D10
D11
D16
D44
D47
All where OK
I have tested the poly caps around the flyback:
C103
C99
C97
C96
They tested all ok
I traced the b+ from the 100uf 250V cap at the psu, If I do that I get all the way to flyback PIN3 with connectivity.
So I tried to de-solder the leg from pin3 and connect the bulb to pin3 . Then I got light, and 145V :dizzy:
So I went back to test the 25V at R153, now i only see 8V and tested 16V at L6 there I now only have 0V :hissy:
princess prin prin:
Your second to last picture is confusing as you sucked solder off pin 1 not 3. Pin 3 is the b+ and 1 is the other end of the primary winding of the flyback that connects to the HOT collector. To test the b+ you need to suck solder off pin 3 (the correct one) and connect the bulb to the pad or something directly connected to the pad like R153 (as in the last pic) or more simply you leave the flyback alone and lift that side of R153 and connect the bulb to it.
perjmolsen:
Hi
Have found out why my volts where low on R32 and L6.......... :hissy:
My battery in my multimeter where low on power!!! :banghead:
Put in a new 9V battery - and tested
R32 = 23V
L6 = 15V
And B+ messured at R153 = 145V
So all my volts are OK. :applaud:
Next step is try to put in a new flyback (HR7191), and see if I still have B+ because if i solder pin1 and pin3 at the current flyback, then my B+ is 0V
And the HOT is good, so it must be the flyback...there is no visual defects at the current flyback.
And one last thing.. how do I open the connector?
I have tried to pull and press on the tabs, but no luck
princess prin prin:
Check if the primary and secondary windings are shorted. 1-3-4 must be isolated from 5-6-8-9-10:
http://www.hrdiemen.com/reparation/flyback/scheme/7191
Check if pin 1 on the chassis (with flyback off circuit) is shorted to ground. You said the HOT and the high voltage caps are good but the damper diodes may not be. If you remove the HOT and bridge pin 1 and 3 on the chassis and the bulb lights up and b+ voltage is present there are no shorts (but HV caps/diodes may be open).
That socket is the worst type without a release mech. I would suggest to replace it. I can give you a free one if you pay for the shipping.