VCU-piggyback

Modding and Technical Issues

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Schnurri
Vic 20 Newbie
Posts: 15
Joined: Tue Jan 16, 2018 5:56 am

VCU-piggyback

Post by Schnurri »

What's the story with the VCU-piggyback (Video Circuit Upgrade)? It was mentioned in Commodores Magazine Power/Play Issue 1 (page 3) and Issue 2 (page 3). What does it exactly do? Best regards, Schnurri
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Mike
Herr VC
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Joined: Wed Dec 01, 2004 1:57 pm
Location: Munich, Germany
Occupation: electrical engineer

Re: VCU-piggyback

Post by Mike »

From the description in those two magazines, the VCU piggyback is a small PCB (printed circuit board) that was (or could be) fitted to very early VIC-20s (and Japanese VIC-1001s) to improve their colour output:

Image

(from http://sleepingelephant.com/denial/wiki ... djustments)

It's the vertically mounted PCB in the photo above. The video amplifying circuitry of the VIC-20 was modified quite often, and is substantially different once again with the CR variant of the mainboard.

Regardless which mainboard revision, their video output (especially on PAL) is greatly improved with the S-Video mod.
Schnurri
Vic 20 Newbie
Posts: 15
Joined: Tue Jan 16, 2018 5:56 am

Re: VCU-piggyback

Post by Schnurri »

Very early VIC 20s were just relabeled VIC 1001s, right? Best regards, Schnurri
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