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<h1>PDP-11/45: VT52 repair</h1>
Sat 16 July 2016
by <a class="url fn" href="https://fritzm.github.io/author/fritz-mueller.html">Fritz Mueller</a>
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<div><p>Replacement oscillator arrived for the VT52, so spent some time getting it back going again. Things got <em>much</em> better
with a stable timing chain, but some glitchiness remained -- tracked this down to the socketed microcode ROMS which
just required a reseat.</p>
<p>Here you can see the new oscillator fitted (silver rectangular can with tie-wrap). The microcode ROMS are the four
socketed chips towards the right in the picture. Interestingly, the schematic I have calls for 8 ROMS of half the size
of the ones that are in here, and indeed you can see the unpopulated spaces for these on the board.</p>
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