The Morse Code Keyer
This model of Morse Keyer is a fun DIY project for cold winter weekend.
During lunch we were meditating with my colleague about older CW Morse Keyer. The built-in flash memory is aging and has limited R/W cycles. A colleague raised question if we have the drive and guts to design a kit. It has to be easy to build, easy to use, and easy to repair. Without the 0402 and 0201 SMD parts. Any 100mA audio transistors in SOT23 for 1c each fit there. Make it simple as possible. With larger parts to ease assembly. Use resources from your junk box. All parts must be replaceable without the "obsolete mystery" of fake marketing. Soldering a processor with 144 pins requires specialized tools, hot air station, and microscope. This is not that case. The whole keyer is housed in an Altoids tin.

Cypress ASIC CY8C27xxx-SXI controller fits this task. With efficient data coding, there is a plenty of program memory left for features and memory banks. The external memory has more than 10E¹³ R/W cycles.
(Some hams buy spared worn-out EEPROMs for their failing Chinese transcevers. That's a temporary solution, the design is sick). It is interesting to rethink the system limits such as "data retention", MTBF. The keyer will run till the battery is completely flat, in contrary with commonly used voltage regulators such as 78L05. Transceivers use mostly 5V interface, not the 3.3V logic.
If you touch the board or buttons, connectors, usual ESD from hand is between 4kV and 8kV. Look at the designs of "Internet experts" in terms of robustness. The wires deliver 40A discharge pulses from your finger directly to the MCU micro controller die. Is it shielded? The mechanical encoder will last one, two years. Corrosion will take care. If you add lcd display, shield it.
There is additional issue nobody will tell before purchase. How the morse code keyer behaves in terms of EMI -interference with radio? Does it generate broadband noise everywhere like the 32bit MCUs?
"A step to technology-independence that succeeded".

Keyer Grounding
A while ago I had a discussion about grounding with Tektronix guy in Portland, Oregon. Use of "Power Planes" in Mixed Signal environment is inherited nonsense from TTL times. Imagine 16-bit ADC on his TTL power plane with FPGAs. He keeps his noisy power planes. I keep designing products that work.

It works the same way as mobile phone technology. One unseen mistake in multilayer PCB board, and the whole device will never work!. Learn your practical part about Maxwell's equations - electrical and magnetic field theory.
It is also a lecture. Some people ask you to confirm validity of their crap and mistakes. Do not fell in this trap!.

Can you do it?
If we see shops with 99.0% products "Made in China", you are missings skills, knowledge, and will.
Passivity results in arrogance, self-importance, and priggery. The empty nothing. Wise people learn from mistakes of others. Unwise don't know, what they don't know. 99% import from colonies is unwise.
The government advisers are fake. They were always fake. They tell some BS about economy.
Connect with your friends or local club members can help you. Amateur radio is about connecting people together and planting mutual cooperation. It is not about show-off about what you can buy from China and throw it to garbage bin next day, next month. Failure is not an option.
Everything published on internet is copied by China in 2 months. This attitude continues since 90's. Presently they are already very busy copying the Morse Keyer. Assembly diagram is available upon request only for none-profit DIY home brew activities. skype.
The brave world only waits what shit comes from China, manufactured by political prisoners. Considering the hypocrisy behind, and priggery supporting CCP. It is a long term society decline, a slump. 40 years of imports and pillage.

China copies the product. After few months you can see the product on Amazon without paying a dime for R&D.
One of my friends set up a fabless company financed out of his pocket. He designed PWM chips. He sold the chip to a company in China. After 6 months the whole China had the chip. Similar situation is in South Korea with schematic diagrams. Schematic diagram communism. (Finally everybody have it). Well, my friend closed his company door for good.

QSL.net censors text, pictures, or implements typos. It was here too many times.

Text.pdf

PCB board: pcb use top layer for routing. The bottom layer is full copper. There are ground vias, or ground vias-holes connected by wires to the bottom layer. It is OK. Local PCB prototyping shop has no resources for plated vias. No problem. (Support your local small business). You can print the PCB artwork in 1:1 scale. (Irfanview).
Use of any Microsoft printing program results in different scale.

Morse Keyer 2 PCB top layer in TIFF file.

- Before you are finished, find somebody in your club who can program the chip with hex file.
Learn about social interaction and mutual cooperation. Cartels love your dependency, and love to lock you to a single chip manufacturer. Typical example is ERA2, ERA4 MMICs Mini-circuits (60mA), or PGA-1 LNAs with no ESD immunity. They will keep you busy replacing PGA-1. Arduino plants dependency on their libraries. "Bare metal" programming is the way to go.

Hex file download
morse_keyer01hi2.zip for initial testing with encrypted and hardcoded cw message:
"cq cq de KF6R.. /mm". Fully operational firmware. You can record and play back your Morse message, and set your speed.


Summary

Learn something. Check, what you can do.

Avoid market monopoly. Plant part sourcing from multiple parties.

Avoid fruitless and expensive firmware updates (Windows 25).

You can program it your way.
Take an older laptop computer. Clean the ventilator area. Open the intentionally sealed ventilator air intake holes. Nearly all computers have sealed ventilation holes from inside covered by foil! Remove the foil and plastic seal by knife. Place there SSHD solid state hard disk and additional memory. Load Linux. It will bring you satisfaction and spare your time. Use only tested and certified programs from "repository". Any different programs with recording, tracking, "share-what for?", or internet "connectivity" and government tracking will bring you trouble and waste your valuable time. Different words for the same thing: No forced updates to intentionally screw your work! Then they send "patches" to keep you in infinite IT/ tasks.

You can modify the micro controller source code. Add your own features.

Programming is in C. Without wasted months with assembly, or high level language library errors (Arduino).
Arduino plants full dependency.

Works with 5V or 3.3 Volts. Your choice.

Use old 3.5mm mono/stereo jacks with springs inside. Recent cylinder-type jacks are unreliable.

Avoid mechanical encoder. The rice encoder will die on you after one year due to contact corrosion. Can't imagine you will fix it on mountain top or remote Pacific atoll. Murphy's law works everywhere, 100%.

The push buttons are hidden in metal can, shielded. Usual constructions from Internet experts are problematic. Everytime you touch any metal wire or connector, it gets 4kV to 8 kV ESD shock. This goes directly to the die. How long it will last?

Avoid processors generating 1GHz wide spectrum full of interference (esp32, fpga). EMI. On a oscillocope probe shortened by the ground wire = loop, you can measure [Volts] of EMI interference.

The flash memory has finite number of write cycles and limited data retention time (generally 5-10y). Minimize Writes. There are multiple technology choices of memories that last longer. Some are radiation hardened for space applications.

The Morse keyer can be used in Beacon Mode with internal 32kHz clk (no crystal required).

What is the best morse keyer? -"The Best Morse Keyer is Made by You!"- .

Become Independent

References
[1] Dave's notes
[2] rice "MegaKeyer"
[3] Good Key and Bad Key
[4] Cypress Semiconductor

MADE by VA3DIW


Enjoy,
3/2023; public web 1/2024