I wish it was smoked HAM, but like the title suggests, I experienced a smoke discharge from a 1972 vintage IH AM radio today. All I was trying to do was identify which terminal was + and which was - on the replacement 4"x8" dash speaker as they were unmarked. The original speaker was badly sun-rotted and crumbling like a dry leaf. I sourced a non-IH, yet vintage 4"x8" speaker that looks to be in great condition. The terminals on the speaker were oriented differently than the stock speaker, so the factory two-prong plug wouldn't connect directly to the speaker. So I made jumper wires from the factory harness to the replacement speaker terminals. I switched the IGN to ACC and turned the radio power dial ON. I could see that the small light bulb inside the radio was lit. I then began touching my jumper wires to the speaker terminals hoping to get some noise out of the speaker. That's when I saw and smelled smoke wafting out of every orifice of the radio chassis. I shut everything down, but it was too late. The old radio smells of crisp bacon and is deader than the hubs of hell. This all happened very quickly. I'd say the radio was powered for roughly one minute before all hell broke loose. Now to my questions...Can powering one of these old radios with no speaker connected, even briefly, burn them up? Or was it just time for this old radio to go mammaries-up? Has anyone had a similar experience?