Category Archives: electronics repair

Genie ISD-990 Garage Door Opener
Lights stay on

Symptom: After the garage door closes the lights will not go out. Pressing the wall switch will not turn them off either.

Most likely solution: the relay controlling the lights is stuck in the closed position.

Here is the garage door opener, its internal parts exposed:

IMG_3189

There is a board for the I/O, remote (the one parallel to the ceiling) and one to control the motor and lights (perpendicular to the ceiling).

IMG_3183

Note where the blue and white wires connect on the board (those wires go to the lights).
You can the follow the traces on the circuit board to see which relay they go to.
The relay is a Song Chuan 801H-1A-C.

I bought mine at mouser.com and here is a link to the specification sheet (PDF).

Remove the board:

IMG_3302

remove the relay:

IMG_3307

and put the new one in.

IMG_3311  IMG_3303

Put the board back in the garage door opener.

Tascam CD-RW700 Repair
Stuck at Welcome!

Problem is with a Tascam CD-RW700 standalone pro-audio recorder. Turn on the power and the unit gets stuck at the Welcome! message on the LCD screen and you cannot even open the CD tray.

Remove the rack ears and carefully open the unit, locate the power board (right hand side when facing the unit).

IMG_5912

The top part of the board handles audio I/O and the bottom part is the power supply to the various boards (the connectors are a good place where to check voltages).

IMG_5910 - Copy

In my case I noticed one of the capacitor (C07 – the black one) had leaked. I also decided to replace the CapXon cap (C02) since it showed a borderline ESR value.

Specs:
C02….4,700 μF(35V)
C07…10,000 μF(16V)

I replaced them with Nichicon branded caps.

IMG_5915

Close, start and enjoy!

Note that I did check the two resistors (R72 and R73) and they were good (desolder one lead to measure the resistance). They should be 470 Ω (1/2 W).

Additional photos:

IMG_6404 IMG_6398LCD board