Maker Pro
Maker Pro

Magnavox mdr557h/f7 dvr

having a problem with the power board with this unit. Blows fuses. Caps and diodes good. Mosfet good. Cant find schematic or replacement parts.
 
Sir ennisdavis . . . . .

To confirm that you are using the proper time lag fuse replacememnt . . . . to further save any more power components from getting crowbarred.
Locate a desk, torchiere or drop light that accomodates conventional screw in based incandescent bulbs.

Place a 60 or 100 watt lamp in it and plug in and turn on . . . let there be light ? . . .then unplug and head for the DVR and use 2 test leads . . . . with their end clips . . .thereby . . . being able to connect the lamp in place of the fuse at the fuse clips.

Plug in and turn on the unit to see if you get a normal cherry red glow as the FWB is charging up
the main 470 ufd raw DC storage cap.
As its degree of charge maximizes . . . the lamps brightness diminishes.

OR . . . . if you have bad power supply parts, the lamp will light up and stay at almost normal 60/100 W brightness.

To be continued . . . . . tune in . . . . . same time . . . . . same station . . . . tomorrow.

73's de Edd
 
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