651
edits
m (→0500 (Z70500 is on the rear side): fix external link) |
m (→Z70500) |
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*''Problems:'' | *''Problems:'' | ||
**[http://www.benophetinternet.nl/hobby/vanmezelf/ZX%20Spectrum%20128K%20video%20fixes%20and%20video%20cables. | **[http://www.benophetinternet.nl/hobby/vanmezelf/ZX%20Spectrum%20128K%20video%20fixes%20and%20video%20cables.pdf Requires TR4 mod for misplaced transistor.] | ||
** Not only should TR4 be rotated but also TR7. If TR7 is mounted in the false direction then the transistor, which normally acts as an emitter follower, only acts as a diode. The base-collector-diode together with R65 realizes the OR function. But in this case A0 is loaded by 470 Ohm which would be avoided if TR7 would be mounted correct. ([http://www.worldofspectrum.org/forums/discussion/comment/834739/#Comment_834739 Ingo]) | ** Not only should TR4 be rotated but also TR7. If TR7 is mounted in the false direction then the transistor, which normally acts as an emitter follower, only acts as a diode. The base-collector-diode together with R65 realizes the OR function. But in this case A0 is loaded by 470 Ohm which would be avoided if TR7 would be mounted correct. ([http://www.worldofspectrum.org/forums/discussion/comment/834739/#Comment_834739 Ingo]) | ||