The image is at http://lwca.org/community/Attachments/slash_composite_crop.jpg.This image shows the analog hardware used to generate "SIW" in slant code (upward ramp = dot, downward ramp = dash). On the top right is 555 timer circuitry to establish the period (tunable and currently about 60 seconds). In the top middle are multiplexer ICs to choose ramp up or ramp down per the "SIW" code. On the top left are op amps to create the ramps and relays to select which is applied in time (tried FET switches but they were too leaky).
The bottom image shows a Spectrum Laboratory QRSS3 waterfall, embedded with an Argo QRSS30 waterfall. The lower signal on the former waterfall is the SIW QRSS6 signal. Unfortunately the image is low resolution so magnifying it to see the fine print won't work.
Of course the best way to generate slant code is with a uP. But none was at hand when the urge hit so a junk box design was pursued instead.
73, Garry, K3SIW, EN52ta, Elgin, IL