At a local junkshop, I bought a Thomson DTR6000AU PVR (it was later found to be a rebadge of a Comstar FGS8800) for a song.
Upon opening, C7 (feedback monitored +5V rail) was bulging, along with CP1 (+12V), C107 (feedback monitored +5V rail), C121, C108, C121, C120 (unmonitored +5V rail) and C3V1 (unmonitored +3.3V rail) being bad.
All of the electrolytics in question were TREC units, with the 450V unit being a "ST" unit.
When C7 loaded down the monitored +5V rail, it caused the +12V rail to rise dangerously high to the point it destroyed the HDD (probably explains why there was no HDD in it when I bought it, with CP1 on the logic board bulging).
The MOV at the mains input was blown (rated at 250VAC, too close for comfort at 240VAC, especially in Western Australia, where it is 254VAC) and replaced with a 275VAC unit. The 400V zener diode after the AC bridge rectifier would have provided additional protection against surges.
All of the electrolytic capacitors were replaced with Nippon Chemi-Con KY Series (the 450V unit being replaced with a 150uF Nippon Chemi-Con KMH Series unit - I recommend that capacitance rating as a minimum), with C111 and C5 being 2200uF units (which I recommend for a PVR unit on the +12V rail)
RV1 was carefully adjusted (initially with the supply disconnected from the logic board) to make sure the output was a safe voltage (it was initially a little bit high).
Rebuilding the remote and placing a hard drive inside (no special preparation required - you will lose all existing data without a prompt!
) made the recorder work again.
Upon opening, C7 (feedback monitored +5V rail) was bulging, along with CP1 (+12V), C107 (feedback monitored +5V rail), C121, C108, C121, C120 (unmonitored +5V rail) and C3V1 (unmonitored +3.3V rail) being bad.
All of the electrolytics in question were TREC units, with the 450V unit being a "ST" unit.
When C7 loaded down the monitored +5V rail, it caused the +12V rail to rise dangerously high to the point it destroyed the HDD (probably explains why there was no HDD in it when I bought it, with CP1 on the logic board bulging).
The MOV at the mains input was blown (rated at 250VAC, too close for comfort at 240VAC, especially in Western Australia, where it is 254VAC) and replaced with a 275VAC unit. The 400V zener diode after the AC bridge rectifier would have provided additional protection against surges.
All of the electrolytic capacitors were replaced with Nippon Chemi-Con KY Series (the 450V unit being replaced with a 150uF Nippon Chemi-Con KMH Series unit - I recommend that capacitance rating as a minimum), with C111 and C5 being 2200uF units (which I recommend for a PVR unit on the +12V rail)
RV1 was carefully adjusted (initially with the supply disconnected from the logic board) to make sure the output was a safe voltage (it was initially a little bit high).
Rebuilding the remote and placing a hard drive inside (no special preparation required - you will lose all existing data without a prompt!
) made the recorder work again.
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