Background

When I got back into the Aquarius in the Summer of 2019, I got a bare bones Aquarius that didn't even have the switch box or cable plug for RF output. I had to hack together a BNC cable with an RCA cable to even see the output to make sure the machine worked. It was frustrating, so I began researching the raw VID (composite) signal coming off of the video chip (TEA1002) of the Aquarius. I hooked a standard composite cable up to it but found the signal was too weak to be useful. I then found a video showing one user's success at adding an inexpensive video op-amplifier, and set about trying to find a similar chip in a more manageable PDIP-8 package that most users could more easily solder. I settled on the AD812ANZ Video Amplifier chip. Included in the chip's documentation was a sample single-supply (+5v) circuit, so I assembled the parts, bread-boarded it, and hooked it up. It worked on the first try. I then found the SND lead and discovered that it didn't need to be amplified, so I passed it straight through to the right and left audio out. After that success, I went through two PCB prototypes and settled on a design that fit within the stock RF modulator's form factor.

This through-hole DIY board replaces the stock RF modulator in the Aquarius computer with a 3.5mm AV out jack, combining composite video and stereo sound (Aquarius only had mono, so sound is split to L & R). This device works for either the NTSC or PAL version of the Aquarius. In addition to the BOM components, this build also requires a 3.5mm/0.125" AV cable that matches the pinout configuration shown below: