Radio Failure
So.... there I was, passing 1,500 feet climbing away from a big International Airport, on the third leg of my QXC when it all went tits up during the handover to the adjacent even bigger International Airport as I was about to transit their airspace.
I acknowledged the new freq and squawk, changed freq and when I pressed the transmit button, it fell apart!
I quickly reached for the other stick and transmitted by using that button, but the absence of sidetone suggested I wasn't going out.
I didn't fancy going back, (unannounced) to the airfield that I had just departed, and as I had been cleared to enter the control zone I continued en route while trying to fly the aircraft, keep a good lookout and plug my headset in to the other side of the aircraft. During this process I heard the zone controller telling me he was getting carrier only but if it was me, then I should continue to transit the zone as cleared.
Once plugged in, I was able to explain I'd had an equipment failure but it was resolved. I flew the last 100 miles by pressing the button on the right hand stick to talk to ATC.
Up until that point, I had thought that either Tx Switch activated both mikes.
Two days later I find out that at least two other club members, one an instructor, were aware that the Tx switch was "iffy" but hadn't snagged it.
Every day's a schoolday.