This post ends my series about the Vectrex gaming system. You likely missed it because I remove the audio track from my videos, but this vintage console has a most annoying characteristic: the horripilating buzz it makes when it is turned on. It is infuriating and doesn’t depend on the volume setting. You don’t have to trust me; just listen to the audio recordings attached to this post. So, I went ahead and installed the Buzz Off kit by Charles Tweedy into my GCE Vectrex. The buzz comes from the design of the Vectrex.
In this design, the main logic board sits flat at the console’s bottom and uses the AY3-8192 chip to generate the sound. However, the audio signal needs amplification before being fed into the speaker (which is right afront on the logic board, facing the player). The odd design choice is to send the signal to the power board for amplification (sitting vertically in the console) using an op-amp (LM386-3). The signal is then sent back to the speaker header on the logic board.
Besides the passable quality of the op-amp itself, the wire bringing the amplified signal back makes an excellent antenna and captures all sorts of electric noises, especially from the CRT. Hence the awful hum. Now, some Vectrex users claim that this is part of the experience and that it should be kept as-is for authenticity reasons. Others, like I, found very hard to go back and play a buzzing model. Think about the pain you have to endure if you code an application with a beehive sitting next to your ear.
No one deserves such torture. Because the kit is not destructive, I can always restore the Vectrex to its original state if needed. Simple and effective! One last note. If you attempt the mod, do it at your own risk, and never ever touch the tube or the power board in general. Because, as Doug Marcaida would say: “it will kill.”
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