Yes, you’ve all thrown away your lunky old CRT monitors, in favour of sleek ultra-thin LCD displays. And, you thought you’d never see another one again…
But this CRT display has a twist! It’s round. It’s small at just 3 inches diameter. And it’s awfully cute.
![Oscilloclock 3-inch CRT VGA Display Assembly - overview](data:image/svg+xml;base64,PHN2ZyB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciIHdpZHRoPSI1ODQiIGhlaWdodD0iMzM1IiB2aWV3Qm94PSIwIDAgNTg0IDMzNSI+PHJlY3Qgd2lkdGg9IjEwMCUiIGhlaWdodD0iMTAwJSIgc3R5bGU9ImZpbGw6I2ZmZmZmZjtmaWxsLW9wYWNpdHk6IDAuMTsiLz48L3N2Zz4=)
Last year, I was approached by a dedicated flight simulation enthusiast, who needed a radar indicator to use in a fighter cockpit replica. The indicator should employ a CRT, for the most realistic look. Could Oscilloclock design and construct such a display?
It didn’t take much convincing! Diverging only temporarily from building clocks, I took up the challenge to create my first raster-scan CRT display unit. In the ensuing months, difficulties sprang forth from every direction in the project, but ultimately I was able to avoid a diraster (sic) and deliver a functional assembly:
See more related videos on my YouTube channel
The Setup
The key component of this setup is a new prototype VGA Board that converts a VGA signal into analogue X and Y outputs. Both analogue intensity and binary blanking outputs are provided.
![Oscilloclock VGA Board prototype](data:image/svg+xml;base64,PHN2ZyB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciIHdpZHRoPSIyMzIiIGhlaWdodD0iMzAwIiB2aWV3Qm94PSIwIDAgMjMyIDMwMCI+PHJlY3Qgd2lkdGg9IjEwMCUiIGhlaWdodD0iMTAwJSIgc3R5bGU9ImZpbGw6I2ZmZmZmZjtmaWxsLW9wYWNpdHk6IDAuMTsiLz48L3N2Zz4=)
Oscilloclock VGA Board prototype
The X and Y outputs drive an Oscilloclock
Deflection Board, while the binary blanking output drives the blanking amplifier in a
CRT Board.
![Oscilloclock Deflection Board - modified for ultra-linear HV output](data:image/svg+xml;base64,PHN2ZyB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciIHdpZHRoPSIxOTAiIGhlaWdodD0iMzAwIiB2aWV3Qm94PSIwIDAgMTkwIDMwMCI+PHJlY3Qgd2lkdGg9IjEwMCUiIGhlaWdodD0iMTAwJSIgc3R5bGU9ImZpbGw6I2ZmZmZmZjtmaWxsLW9wYWNpdHk6IDAuMTsiLz48L3N2Zz4=)
Deflection Board – modified for ultra-linear HV output
![CRT Board - heavily modified for improved frequency response](data:image/svg+xml;base64,PHN2ZyB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciIHdpZHRoPSIxOTAiIGhlaWdodD0iMTQzIiB2aWV3Qm94PSIwIDAgMTkwIDE0MyI+PHJlY3Qgd2lkdGg9IjEwMCUiIGhlaWdodD0iMTAwJSIgc3R5bGU9ImZpbGw6I2ZmZmZmZjtmaWxsLW9wYWNpdHk6IDAuMTsiLz48L3N2Zz4=)
CRT Board – modified for improved frequency response
Blanking isolation, heater, and HV supplies are provided by a
Power Board.
![Power Board - with improved optocoupler](data:image/svg+xml;base64,PHN2ZyB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciIHdpZHRoPSIzMDAiIGhlaWdodD0iMjMxIiB2aWV3Qm94PSIwIDAgMzAwIDIzMSI+PHJlY3Qgd2lkdGg9IjEwMCUiIGhlaWdodD0iMTAwJSIgc3R5bGU9ImZpbGw6I2ZmZmZmZjtmaWxsLW9wYWNpdHk6IDAuMTsiLz48L3N2Zz4=)
Power Board – with improved optocoupler
It all looks so easy! But
noooo. Astute readers will recall from other posts that
every Oscilloclock project involves sleepless slumbers, horrific hair-pulling, and forgotten family members. Let’s see what caused me grief this time…
Continue reading →