Can you post a photo of the soldered side?
Also, start with the pot in the middle and do not rotate it to the ends. At one end, the discharge transistor (pin 7) is connected directly to V+ and it won't like that.
Hmm.. it loads OK on Firefox Windows but winds up in the downloads folder on Safari and Firefox on iPad. It’s viewable from there. Same on some other PDFs I the thread. Something new maybe?The schematic shows an error and cannot be seen.
You're absolutely right now that I look at it.Another problem is that with only a single resistor to limit LED currents then all the LEDs that are turned off have much more reverse voltage than the 5V shown on the LED datasheet as the maximum allowed reverse voltage.
Using your multi-meter, set to measure DC Volts with the unit powered up measure between pin 3 of your clock chip and ground. Does the meter bounce around or does it give a steady reading? The idea here is the clock chip, likely a 555 timer acts as a free running multi-vibrator. The polarized cap and the pot control the frequency (how fast the LEDs chase). Pin 3 of your clock drives what is likely a 4017 decade counter which counts up 0 through 9 and resets. Your images look like things are installed correctly. I can't imagine 3 of these things not working. We are missing something here.
View attachment 189459
Ron
Adding more should not be too difficult. You have as mentioned, a clock signal generated by your 555. That clock signal is passed along to a 4017 CMOS Counter Divider. This allows a visually appealing LED chaser effect. The 4017 does have a "carry out" pin which can be used to drive another 4017 resulting in what is known as "cascading 4017 counter/divider chips". The downside I see is as the first chip increments up once it provides a carry out it will start counting up again and the second chip will increment up one count.In addition as I work on this, I am trying to figure out how to get two of them to work together, so I can use fiber optic cable to run a marquee theater sign in HO scale.
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