21 May
2012
21 May
'12
12:44 p.m.
So I finally got my VT220 put back together! I have one I saved from the dumpster from a
plant floor,
but it was incredibly filthy. I disassembled it, cleaned it thoroughly, and put it back
together (over a
duration of 6+ months), and amazingly it still works! So, I had to hook it up to my
MacBook Air, just
for fun. Works like a charm, but characters on the left seem slightly fuzzier then
others. Maybe that's
just because I've been staring at the razor-sharp screens on my MacBook and iPhone
too long, and
the fact that this thing's 26 years old, but is there a way to sharpen them up a bit?
Even if not, it's still darn funny to have a physical terminal on my MacBook!
I thought htere wsa focus preset on the video.monitor PCB, the presets
are all labelled on the paper overleay.
However, AFAIK this affexcts the focus over the enitre screen. There is
no way to focus one wide rather than the other. Now, the focus anode
voltage is derriced from the flyback transforer, as are most of hte other
CRT votlages (some of which could also affect the focus). So if the focus
is much better at one side htan the otehr, it suggests one of those
votlages has horizontal-freqeuncy ripple on it. Which to me suggests a
defecive capacitor in one of the rectifier cirucits hung off the flyback.
-tony