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I took home a spare VR241-type monitor on a property pass. If you have a
VT241 at home, you could do something similar.
Connecting a DEC VR241 to the Atari is not too difficult, but it does
require some manual dexterity to work with those nasty 13-pin DIN
connectors. I obtained one of those 13-pin DIN connectors from the number
in (412) area code posted somewhere earlier in this file ($5.00+COD and
postage), and built a cable that ended in R, G, B, and SYNC BNC
connectors, as well as an RCA connector that attaches to a nearby stereo
for sound (including keyclick).
The disadvantages to using the DEC monitor are:
- The Atari expects an overscan monitor. The VT241 shows the
entire picture in a portion of the center of the screen.
- There is no sound built into the monitor, you need to hook up
some external amplifier to to audio output pin.
- You need to make your own cables.
The advantage to using the DEC monitor is:
- Very high resolution - high enough for DEC's 800-pixel devices,
so it works great with only 640.
If your particular edition of ST generates composite video, you
are in luck, because you can use this signal as the sync signal to
any RGB monitor that accepts external sync. In my case, a
1040STf, the "composite" pin was a dead pin, and I needed to mix
the two Atari TTL SYNC signals to produce the single sync signal
needed by the DEC monitor. I used two 330 ohm resistors, which
fit (rather tightly) inside the handle for the 13 pin connector.
(I first tried to wire-or these signals, assuming they were
open-collector signals. Wrong.) To make working with the
connector easier, I tacked short pieces of wire wrap wire to the
pins I needed, and soldered the other ends of the little wires to
the coax. I used the narrowest coax I could find, RG174, so that
four of them, plus a fifth VERY NARROW shielded audio cable (Radio
Shack microphone cable), could fit out the hole in the back of the
connector. (I needed to remove the strain relief to do this.)
ATARI (13 pin DIN) VR241
----- -----
Red-----------------------------Red (BNC)
Blue----------------------------Blue (BNC)
Green---------------------------Green (BNC)
H. Sync---/\/\/----+
330 ohm +------------Sync (BNC)
V. Sync---/\/\/----+
Stereo
------
Audio out-----------------------Aux In (RCA)
GND--------------------to all coax shields and audio shield
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