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The service manual was a copy of the original from Wirlpool. The quality was good, all neccecary information was available including the service-codenumbers, so I could order the right part to be replaced for repair.
Downloding was no probem after the payment.
Thanks for the service!
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Good,readable manual. I found other manuals that were not readable when it came to part ID, but the one downloaded from owner-manual.com was better than expected. I will do buisness with owner-manual.com again.
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Service Manual that I received was very helpful to me. Thank you.
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The manual is well organized and is easy to read. The chapters are following normal way to proceed.
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This scanned manual is well done in that most all the pages except for one is straight and clear- the way I would do them. One page was upside down but that happens. For the money that is charged on this site you get a pretty good deal. Now with complex repairs, I still prefer to us paper manuals which I have to buy at stereomanuals but the one I got here was much less than the $45 he was charging but this is a larger than normal manual for three different units. I am a picky manual user because I have used original manuals from Sony and Teac.
Model 185B (3) The voltage across staircase capacitor C236 increases, and is applied, through SCANNING switch S203C/D, to unity amplifier V201AQ210, increasing output of the generator by the same amount; this output is the horizontalscan voltage. (4) After comparator blocking oscillator pulse decays, diode CR215 becomes reverse-biased again, and prevents charge on capacitor C236 from leaking off. (5) DENSITY contrbl R255B is in the charge path of staircase capacitor C236. DENSITY permits limited adjustment of charge-path resistance, thereby determining amplitude of staircase steps by controlling amount of charge added to staircase capacitor each time blocking oscillator fires. (6) The output of unity amplifier V201A-Q210 is applied to transformer T203 in such a way that a bootstrap action results. Thus for a given density, the same amount of charge is added to staircase capacitor C236 each time, which results in staircase steps of equal amplitude.
Section IV Paragraph 4-84 (7) When voltage across staircase capacitor C236 reaches about +15 volts, reset blocking oscillator Q209-T204 fires and discharges the capacitor. The staircase is thus reset and starts over again. 4-84. RESET BLOCKING OSCILLATOR. When the staircase voltage exceeds voltage on collector of Q209 (approximately 15 volts), diode CR217 becomes forward-biased, current begins to flow through collector winding of transformer T204, and capacitor C236 effectively becomes the voltage supply for blocking oscillator Q208-T204. The effect of this current flow is transformer-coupled to the base of Q209, which causes blocking oscillator to fire, essentially dropping collector of Q209 to ground. The resulting current-flow through CR217 and QZOQdischarges capacitor (2236, thereby resetting the staircase. It might be pointed out here that the amplitude of the staircase signal remains constant. The height of each individual step can be varied by adjusting R255B a s mentioned in paragraph 4-83, step d (5). The result of varying the height of each step is to change the number of steps per staircase, which changes the number of samples per sweep on the crt.
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300
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HORIZONTAL SIGNAL
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TO COMPARATOR AND HORIZONTAL AMPL.
Figure 4-10. Staircase Generator 01255-1 4-11
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