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Hantarex polo 25-28 multisync horizontal with control (SOLVED)
princess prin prin:
You can check C173 and C184 which is in parallel with D141, then T114, T301 and IC301.
perjmolsen:
--- Quote from: princess prin prin on October 30, 2019, 03:56:36 am ---You can check C173 and C184 which is in parallel with D141, then T114, T301 and IC301.
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Hi
I have now tested C173,C184,D141,T114,T301 all components test OK.
I have no idea in how to test IC301 (TD8145) - I might order some new ones in china. :)
I have also done a electrolytic cap kit on the chassis, also tested the volts from the PSU, they are all as in the schematic.
But I am still unable to adjust the picture in the sides, it is still curved.
There is some jumpers that I am uinable to find any information on, what do they do?
K104 (with the green plug) it is pluged in the middle
J107 (with the blue wire) it is pluged in to K117
I have noticed on your picture the J107 (blue wire) is connected to K117 pin 1?
princess prin prin:
--- Quote from: perjmolsen on November 01, 2019, 04:25:28 am ---I have now tested C173,C184,D141,T114,T301 all components test OK.
I have no idea in how to test IC301 (TD8145) - I might order some new ones in china. :)
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You can try but I think the IC rarely goes bad. At this point an oscilloscope would be useful to check if the sawtooth signal from the vertical deflection is arriving at the IC and if the correcting parabolic signal is coming out of it. Is the IC getting power (25V) at least?
--- Quote from: perjmolsen on November 01, 2019, 04:25:28 am ---There is some jumpers that I am uinable to find any information on, what do they do?
K104 (with the green plug) it is pluged in the middle
J107 (with the blue wire) it is pluged in to K117
I have noticed on your picture the J107 (blue wire) is connected to K117 pin 1?
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The capacitance across the hot collector line and the horizontal deflection yoke is used to correct raster distortion in the form of compression at the sides or in the center (similar to linearity but symmetrical). This is called S-correction and the S-correction capacitor is C181. Different tubes and different scan frequencies require a different correcting capacitance so by setting the jumper across pin 2 and 3 of K104 you modify the capacitance of C181 with C182 in parallel with it when the chassis is at 15KHz. By setting the J107 jumper on pin 1 of K117 you put C200 in parallel with C180, the retrace capacitor. The modification of this capacitance is necessary when the chassis runs at 15KHz.
perjmolsen:
--- Quote from: princess prin prin on November 01, 2019, 06:46:00 am ---
You can try but I think the IC rarely goes bad. At this point an oscilloscope would be useful to check if the sawtooth signal from the vertical deflection is arriving at the IC and if the correcting parabolic signal is coming out of it. Is the IC getting power (25V) at least?
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Hi
I have tested that there is 12.4V at pin 1 at the IC301.
Hmm now it would be an idea to put together the china oscilloscope, and figure out how to use it :D
I guess that i need to test all the testpoints as mentioned in the schematics
princess prin prin:
--- Quote from: perjmolsen on November 01, 2019, 08:24:07 am ---I have tested that there is 12.4V at pin 1 at the IC301.
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It needs 25V at pin 6.