ComputerSphere – converting the knobs to buttons

Before I can mount the motherboard, I needed to return the three knobs back to their original location as I wouldn’t be able to do this with the motherboard in the way.

Originally these knobs were used for volume control, and some form of picture fine tuning.

As we are all in a digital age, I didn’t have anything that I could control with pots, and the two things I do have (channel and volume, both up down buttons) will be controlled with the two main knobs (coming soon). So I came up with a very simple crude method to convert the knobs to more useful push-buttons.

Here is the assembly of the original potentiometers (one black knob missing).

The original Videosphere tuning knobs

Here are the standard red push-button switches that I had lying around.

Three generic red push-button switches

And here is the idea, cut the original black knobs in half and mount the push-button switches underneath.

The concept, the knobs converted to buttons

I create a basic bracket from some folded sheet metal and mount the push-button switches.

The knobs mounted in a sheet-metal bracket

On first test the black knobs were slipping of the head of the push-buttons as there was too little surface area. To solve this I epoxyed some small sheet metal channels to the base, this stopped the knobs slipping off.

Here they are all sitting on the heads of the push-button switches.

The push-buttons with the knobs sitting on top

What is looks like inside when mounted to the Videosphere.

The whole thing mounted inside the Videosphere

And what it looks like from the exterior, looks pretty much the same as it originally did, except we have three useful buttons.

Looks exactly the same viewed from outside

Now what’s going to be connecting to the buttons, well, the LCD TV has seven buttons already, two for volume up and down, two for channel up and down, one for ‘menu’, one for ‘power’ and one for ‘TV/AV’. The three buttons will be used for the later, with the power button of the LCD TV sharing the same button as the computer.

Here is a shot of the original LCD button PCB, I keep the whole thing and mount it inside as it allows me to trouble shoot things. The IR receiver for the remote I thought of keeping, but couldn’t think of anywhere good mount it, plus having already mounted the LCD made it very difficult to drill holes anywhere close to the LCD.

The LCD TV control panel PCB

The following shows the button PCB mounted and buttons wired up, also added the VGA cable.

The original TV LCD control panel PCB mounted and wiring started