Amateur radio operators had jargon LONG before the first byte was bitten.
When conversing in Morse code (aka CW or 'continuous wave'), where each letter can have up to 6 presses of the telegraph key, words naturally are abbreviated by the radio operators.
Of course, Mac translated my Morse code abbreviations spot on.
The abbreviations Mac & I used are no different from the abbreviated slang now used for a very similar reason in SMS or TXT messaging, where each letter/number may require as many as 7 keypresses.
The radio I pictured was a Heathkit HW-101 radio transceiver. All vacuum tube, covers 3.5MHz-28MHz with CW or SSB (voice). Sold in kit form for the most part (though you could buy assembled radios at a high cost), very popular throughout the 1970s. Lots of ham ops used the venerable old Hot Water 101 to talk to the world long before you could easily post an email message for someone overseas. It was most teenaged hams' dream radio back in the day.
I still have one.
Aaaaaaaaaaaaanyway, back to the dope growing thing.