Building NT7S's Code Practice Oscillator: Breadboard attempt 1

I’m currently working on NT7S’s Code Practice Oscillator. I was intimidated for awhile even after buying all the parts for it, but I finally went for it yesterday and…

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I realized I got the wrong kind of switch; but hey! I got an LED lit and I can switch it on if I want to!

I attempted the rest of the circuit, despite a lot of problems, and because of those problems (and being a beginner), I can’t properly troubleshoot–despite trying for an hour with my multimeter. At the end of the day, I broke down the breadboard to just the LED.

Here are the problems I noted:

  1. The trimpot I got doesn’t fit in the breadboard easily, so I substituted with a 3.3k resistor. I am now thinking that this is the main problem (or at least the first to address). As I looked at trimpot schematics I realized that they have 3 separate pins, not 2 like a resistor.
  2. The wrong switch: I got a SPST-NO (momentary on) rather than an on-off like for a lightswitch. This, at least, is an easy fix with my wallet. For now, the switch is out, replaced by a wire.
  3. 3.5mm stereo jack for headphones: not so much a problem with the hardware, so much as a problem with the user/builder (me!). First, the schematic calls for a mono jack but I had to be extra and get stereo. Second, I have no fucking clue how to wire these 5 pins and every search engine result is about soldering/fixing the plug and not the jack! I couldn’t wrap my head around it. Please forgive me, but I cut the wires of the 3.5mm mono from my existing practice oscillator (MFJ-557) and attempted to jerryrig additional wire to connect to my breadboard, because I couldn’t figure out how to uninstall the actual headphone jack from the plastic enclosure. Of course, since nothing else is working, I have no idea if the jerryrigging worked or not. Perhaps I shouldn’t have snipped so soon.

I’m going to try getting that trimpot in there for my 2nd try. And if I can’t bend them in, I’ll solder leads to the trimpot pins. While I’m soldering, I may as well solder longer leads to the jack I commandeered, too…

Should I have started on an easier oscillator/schematic? Maybe! I did decide I’d like to build a stepped tone generator (aka the Atari Punk Console) at some point. So if my 2nd attempt fails, I will probably take a break and attempt the APC instead. Less components, hopefully less opportunity for failure, and less frustration for me. I don’t want to become so discouraged that I want to quit. But this project so far is showing me I am not as well-equipped or as knowledged as I thought I was. That’s okay. I’ve already had several private temper tantrums about it.

Hope all is as well as can be for you, reader.