This customer wanted a Blacet Time Machine in an Aries format. I needed to use small knobs and designed the panel to match the layout of other similar Aries modules. I kept the font for the Time Machine legend and MOTM graphics for the switch.  This is a FrontPanelExpress printed panel.

Sharp-eyed readers will note that the Regen control is +/- so should have looked like this. Oops, well now it's unique.

He bought the Kit from Synthcube less the panel and knobs and I made the bracket out of 0.050" aluminum. I made a MOTM to Dotcom power adapter for his cabinet.

Operation

This particular Time Machine has a peculiarity that I have not seen before. When rotating the Delay knob from 0 to 10 slowly, everything worked just fine. But if the Delay knob was turned fast, the signal had significant high frequency noise. Turning back to about 7 and the noise would disappear. Turning slowly from there would work as normal. I could see this noise modulating the output of the BBD so thought it was an issue in that area of the circuitry but the supplies, clocks, and input signal all looked fine. I then monitored the filter clock from the 4046 PLL and discovered with a quick shift of frequency that the filter clock would synchronize at a much higher frequency. The part was a NXP HEF4046BP. Suspecting this as a more modern part, I went through my stock and found a vintage Motorola MC14046B which worked perfectly.

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