Doug Hoyte has made his own devise to assist with morse code transmission.
This is the keyer pared with a straight key
A dual-paddle (iambic) key is the preferred key for the project.
The guts of the box.
This keyer has a robust set of functions and can be built for less than $40.
The benefit of using an electronic keyer like this is that the keyer’s internal timing circuits determine the duration of the dots and dashes, and the spacing between them.
Be sure to check out Doug’s website and check out his detailed write up on the project. He also made his code available on GitHub.