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Toshiba D-VR7 DVD/VCR Combo
March 23, 2025
Over the years Toshiba released a number of different models of VCR / DVD combo units, today we will explore the Toshiba D-VR7 which has not only VCR / DVD playback, but also DVD recording and HDMI upscaled output from both VHS and DVD sources. When plugged into power this unit briefly lit the front VFD display, showed a 'Load' message followed by some noises from the DVD drive and eventually powering off, all in less than 30 seconds. It seemed that no combination of button presses or modes (VCR or DVD), disc in or out, would show any result other than a swift power off. Time to take the cover off!
With the cover off, the tuner PCB can be seen in the upper left, VCR deck just below, and the DVD, including PCB with upscaling electronics on the right. Funai, a Japanese manufacturer was responsible for the production of both the Toshiba and Magnavox brands, and so there are many decks that have this same overall layout and architecture across the three brand labels. Visual inspection doesn't reveal any obvious issues at this level.
Getting to the power supply requires removing four screws from the corners of the DVD drive and either disconnecting the flex cables in the left side, or gently flipping the DVD drive up and towards the VCR deck so that it sits upside down with the flex cables still connected.
With the DVD drive out of the way we can get a visual on the power supply. There does not appear to be any puffed capacitors, scorched or cracked components.
I worked through checking the ESR on the power supply capacitors, reviewed many of the resistors for value and also checked the diodes. Everything tested ok. Fortunately I had an identical unit here which was working well, so I swapped power supplies and there was no change in behavior, the unit still powered off within a few seconds which suggests that the problem is not likely with the main power supply, but elsewhere.
Reviewing the schematics it shows that the power supply flows through a flex cable to the main board, and works through another power stage. There appears to be regulators for 1.8V and 3.3V as well as switching for 5V, 9V and 11V as well as passthrough for some higher voltages used for the vacuum florescent display.
The board is covered with jumpers which provide a nice place to check various voltages. In this case as I worked through the various rails I noticed that the PON+5V-MOTOR line appeared to be acting strangely.
The schematic shows that Q1057 switches the +5V rail and I confirmed that while the nearly 6V was present on the base, and the 11.6V appeared on the collector there was nothing on the emitter. Testing showed that it had failed.
After removing the transistor the voltage rail was still showing as shorted to ground. The schematic suggested C1544 would be worth looking at.
Looks like C1544 is definitely shorted, 0.02 ohm!
Replacement capacitor installed, and the short now gone. Also installed a replacement for Q1057.
With the capacitor and transistor replaced the +5V line appeared to be working as expected. I was then able to power on the unit and it stayed on. I loaded a DVD into the drive and the disc spun up and displayed on the screen. Next I loaded a VHS tape and.... chaos. The tape was dragged partially in, tried to eject, plastic gears ground, belts strained and eventually the deck powered down.
Looks like there will still be more to be shared on this one, stay tuned!
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