uPD 858 ssb chassis arduino control

[TM86]

And now I'm getting nothing on the channel display. I had seen a promising change on the ones digit looking almost right with an extra segment lit, then nothing. MCP23017 will no longer respond.

So now I'm stuck with a completely dead project until I can get some parts in.

Only reason I can think that the first one went so easy was too fool me into thinking the second one would be as well.

 

[nomadradio]

My bet is on my wiring job, though.

Ancient principle called Occam's Razor. Says that all things being equal, the simplest explanation is the most likely.

73

 

[TM86]

My crappy wiring job is the most likely culprit. I received some new MCP23017's this week, and started building replacement boards for the display and PLL interfaces. Hooked them up on a breadboard to make sure they both worked. Luckily they did, or at least didn't throw error messages.

I did notice that the display ones digit had the same problem as before, one extra segment lit. Tracked it down to a trace on the strip board that didn't get cut all the way through. I thought I had checked that, but apparently not well enough. Cut it, again, and retested. Ones digit now working perfectly, just like the tens digit.

Don't know if I'll get both of these installed into the radio this weekend or not. But at least now I have working chips. The dead ones were holding up progress a bit.