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(This question is a bit close to 'what to buy', but examples given are just such, as there are other suppliers) These are not wide ones, but two within one package. Looking at the back will show that each pair is wired separate (AFAIR simply in parallel). Such dual package LED were already back then special types. Nowadays they are no longer needed, as LED ...


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The early PET models (all 2001, early 30xx) with discrete video circuitry used 60 Hz in all models worldwide. The later PET models (later 30xx, 40xx/80xx/8x96/9000) used a 6545 CRTC chip where the ROM could set the refresh rate. (These can usually be identified by the ROM providing BASIC 4.0.) Candian/U.S. ROMs set a 60 Hz refresh rate; European ROMs set a ...


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TL;DR: Non-CRTC PETs (Original PET, early 30xx) are fixed to 60 Hz. CRTC (6545) based PETs (40xx/80xx/8x96/9000 - *1) use screen refresh rates set by its ROM (*2). 50 Hz for European machines, 60 Hz for US/Canadian units. Regarding the details: For the European models there was no need for compatibility with European television standards as far as I'm ...


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Commodore 128D has an internal PSU so you don't have the risk to have a faulty external PSU, typical for older C64 and C128. Se this other answer: What is the proper way to test the PSU output for a Commodore 128D? Commodore motherboard doesn't have an RTC battery and doesn't use tantalum capacitors so you don't have some problems that plaugue Amiga and ...


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There can be no one size fits all recommendation for all vintage computers. For example some DEC power supplies incorporate an over voltage circuit that short-circuited the output of the power supply. If you attempted to apply power with the power supply disconnected from the computer this circuit would trigger. If you made major changes to the internal ...


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My advice for the first start: Let the computer slowly warm up to room temperature. Perform a careful "audio test" - I mean tilt the case or slightly shake and hear. If some strange noise appears, it would be better to open it and find a part making the noise. It could be a piece of plastic or something torn off - a wire or some other part. Check all ...


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The Wikipedia page on PETSCII is unfortunately very wrong. I advise you to have a look at the "talk" page. For reference I'm copying my own contribution there with some elaborations: Instead of "shifted" and "unshifted", the two text modes were commonly called "lowercase" (or sometimes "business") and "graphics" mode. Since the shift key sets the high ...


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