Here is a circuit I designed, I call it the “Fullerwell”. It’s an 18 watt amp, basically a 5E3 preamp with cathodyne phase inverter mated to a Marshall model 1974 power amp. Built it in a 1×12 with a Jensen P12R but I’m sure a greenback would sound good too.
In the slides there are a few insignificant errata, here are a few I know of and I’d appreciate it if anyone spots something that looks off just let me know, thanks in advance.
Errata:
1) slides 5&6, I didn’t have all of the necessary KiCad libraries so some of the switches may look odd or oddly wired in this schematic, just refer to the wiring diagrams, those are correct for the switches.
2) slides 5&6, same as previous for the transformers — they may look funny here because I cobbled them together from other transformer symbols in KiCad. I used the Heyboers listed on slides 8 and 16.
3) slides 5&6, same as previous for the rectifier tube. I used 6CA4 (EZ81) as listed on slide 9.
4) slide 19, R7 is listed as the PI tail load BUT R7 is actually the PI bias resistor.
5) slide 19, R18 is listed as “V2 Master Volume Leak” but there is no such thing, R18 is the PI tail load resistor.
6) slide 21, these photos were taken prior to some modifications I later made, slides 22 and 23 include the modifications (added a jumper on the B+ bus, the red wire; modified high side of R24, originally had it soldered before both voltage dropping resistors but it needed to be between them, so that’s why there is a black jumper wire in there now).
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.
Have an amazing project to share? The Electronics Show and Tell is every Wednesday at 7pm ET! To join, head over to YouTube and check out the show’s live chat – we’ll post the link there.
Electronics — How to make your own magnetic field probe!
Python for Microcontrollers — Python on Microcontrollers Newsletter: New Releases of MicroPython and CircuitPython and more! #Python #CircuitPython @micropython @ThePSF
