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complete part-lists and pcb layout, schematic diagram is good enlargable,
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Excellent, fast delivery, excellent product. Good luck!
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This manual is for the usa model only. But it is clear
, accurate and comprehensive, including board layouts and schematics.
I found it extremely useful for my mitsubishi dp-86da, but the same diagram would also work for the realistic lab5000 and hi fi 80. Thanks.
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Great to have extra resources for Service Manuals, Now days you can really not trouble shoot efficiently without one , Wayne at IRIONS TV & ELECTRONICS REPAIR Clearwater , Fl. 33755 727-446-7955
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For five bucks you can barely buy a hamburger. Or for the same five bucks you can buy a service manual. Much more useful. (and better for your health, depending on where you buy your hamburgers).
Yes, there are free manual sites out there, but if they don't have what you want, you have to pay.
And five bucks isn't much. Not for full specs, schematics and adjustment and parts replacement procedures.
My only criticism is that grayscale illustrations aren't well rendered, but I've seen worse.
Schematics and text are clear.
I'll be happy to purchase from here again.
Mike
[email protected]
Chapter 6
B) Reduce input harmonic current Normally switching power supply circuit is capacitor input type. Input current of this power supply has many harmonics, because of the conduction angle of input current is narrow. Therefore, an input current is distorted and this is a cause of low power factor. Main purpose of Power Factor Correction Control Circuit is reducing input harmonic current. MC101 senses input voltage (through R106, R107, R156 to pin1 of MC101), then compare the sine waveform and control Q1, Q2 (MC102) switching as correct sine waveform. C) Over current protection The peak current through Q1, Q2 (MC102) is detected at pin 2 ,pin 4 of MC101 as the voltage across R114. When the drain current of Q1, Q2 (MC102) goes over a certain limit, control ON-duty of them, and MC101 turns off. D) Over voltage protection PFC output voltage is adjusted at 12 pin of MC101 voltage by VR101. Even if this Connection to be open, it must be protected. Over voltage protection stops oscillation in Q1 and Q2 by activating the over voltage protection of PFC control IC in MC101 when PFC output voltage becomes over voltage.And the over voltage protection starts oscillation again when voltage goes down to a certain level, and it repeats oscillation and stop. E) (Inrush current suppression circuit) Not related by PFC, but include inrush current suppression circuit . (TH101) This circuit is to reduce (big) charge current through P2 lamp drive (Ballast) power supply and Charge current C114, at AC input timing. 3) Switching Converter The main parts of switching converter are transformer T101, switching MOS FET Q3 (MC102) and output diode D201, D202. This converter is Fly Back type. This means that energy is transferred from the primary to secondary when Q3 (MC102) is off. The main output is 12V output and auxiliary output is 15V output. 4) Control Circuit a) Start up When AC input is ON, power source of IC101 is supplied from R129 R132 and start switching and then the converter is start. Once the converter begins switching, power source of IC101 is supplied from B1 winding of T101. b) Output Voltage Control The stabilization of output voltage is controlled by Pulse Width Modulation (PWM). It is stabilized at 12V by resistance ratio of R206 and R207 based on the standard voltage at IC201.This stabilization is done by feedback from the secondary circuit to the primary circuit through Optoisolator PC102 and adjusting the level of current drawn from pin 2 of IC101. When 12V output voltage is above the control level, IC101 to shorten the on-time (duty cycle) of Q3 (MC102). This cause the average output to decrease. When the output is below the control level, on-time (duty cycle) is increase, thereby increasing the average output voltage. c) Over Current Limit The peak current through Q3 (MC102) is detected at pin 3 of IC101 as the voltage at both ends of R147. When the drain current of Q3 (MC102) goes over a certain limit, IC101 turns off Q3 (MC102).
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