Nice to see RTL (resistor transistor logic) circuits again! They were my introduction to digital logic back in the mid-1960s. I was getting into ham radio at t

Nice to see RTL (resistor transistor logic) circuits again! They were my introduction to digital logic back in the mid-1960s. I was getting into ham radio at the time, and my neighbor across the street was a sales engineer with Motorola. He saw me putting up an antenna and said "hey, it looks like you're into electronics, let me know if you can ever use some free samples of our integrated circuits. Here's a databook to get you started." I really wanted to make an iambic Morse code keyer. This is the kind that has a paddle with two independent levers, one for dits and the other for dahs, and if you squeeze them both at the same time it alternates dits and dahs for you - thus the name "iambic" [1]. So I designed a circuit using the RTL chips, gave my neighbor the parts list, and a week later got a nice box with the parts I needed. Put together the circuit and it worked! Of course I didn't know anything about RF shielding, and RTL circuits were particularly susceptible to interference. So when I hooked the keyer up to my transmitter and tried making some contacts, it mostly worked, but sometimes it would just start generating dits and dahs all on its own because the transmitter would feed back into my iambic circuit. Naturally the hams I contacted started laughing at me (as much as you can laugh in Morse code) and said "what a lid!" [2] It was fun though. [1] "a line of verse with five metrical feet, each consisting of one short (or unstressed) syllable followed by one long (or stressed) syllable": https://en.wikipedia.org/wiki/Iambic_pentameter#Example https://en.wikipedia.org/wiki/Iambic_pentameter#Example [2] https://boards.straightdope.com/sdmb/showthread.php?t=324119 https://boards.straightdope.com/sdmb/showthread.php?t=324119