Joseph KL7JHM is the author of a very unconventional CW transmitter for the 40 meter band. Only TTL circuits are used - 7400 and 7403. At 5V power supply, the output power is approximately 250 mW, at 6V up to 360 mW. The output impedance is approximately 50 ohms.
The wiring consists of two parts: an oscillator with IO 7400 and an output stage with IO 7403. Reviving the ten-part transmitter does not cause any problems, as long as the wiring error was not corrected. We key the supply voltage.
[1] 40m TTL QRP TX – KL7JHM, Floor No. 33, Winter 1982/83