Sonic Impact 5066 Amplifier Upgrade - Page 9 of 10
After soldering everything in place per my schematic, I decided to make some changes.
I found out that the LED on the SI board is not 12VDC but rather more like 2 VDC. Therefore my green panel 12 VDC LED I wanted to power in parallel to the board's red LED would not work. Instead of going to buy another lower voltage LED I simply removed it and plugged the hole with a chrome hole plug.
I also added a second DC power jack. This jack could be used to allow a wall wart to power the amp if the SLA battery ever died. I did not make any special provisions in my electrical schematic to prevent someone from trying to run the wall wart and the battery charger simultaneously so I slipped a black plastic plug into the "wall wart" DC jack to mechanically prevent anyone from using it without first prying out the plastic plug. I'm giving this amp away to my parents as a Christmas gift and hooking it up for them so it will be safe.
Here are some photos of my finished project.
| Interior from front |
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| The right hand switch allows the SLA battery to charge (yellow LED) in the down position and allows 12 VDC to go to the power switch in the up position. The left hand switch allows power to go to the SI board in the up position. Note that I removed the original 12 VDC green LED and replaced it with a chrome hole plug. Note that I also cut some length off the potentiometer's shaft to allow the volume knob to mount closer to the panel face. |
| Interior from top |
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| Note how tiny the SI board is! The battery holders are actually brackets used in the enclosures to attach ceiling fans or ceiling light fixtures. The SLA battery takes up most of the room in the enclosure. I mounted my own custom rubber feet in each corner of the base. |
| The SI board and back panel detail |
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| Front panel detail |
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| Interior from rear |
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| Note the addition of a second DC jack (plugged) for using a wall wart power supply if ever necessary. |