Speedo Needle Bounce/Cruise Control Transducer

I had an earlier post about a bounce in my speedometer needle. I received several great pieces of advice on lubing my cable and/or replacing the cruise control transducer. I drove it about 500 miles this weekend to an NCRS judging meet in Knoxville, (2nd Flight first time judged for a driver with 77K miles), and the needle kept the same mild bounce and would occaisionally swing a bit more wildly.

On my return after the meet I decided to try the cruise control which worked fine about 6 months ago. I was going about 80 and when I engaged the cruise and it immediately started accelerating. I touched the brake to disengage and waited a couple of minutes and tried agian. It accelerated again on it's own and after I disengaged with the brake the speedometer needle bounced a couple of times and then fell to 0 and stopped working altogether. The odometer and trip odometer both quit working as well.

My best guess is that it is the cruise transducer but thought it best to get a second, third,...etc, opinion before moving forward. As always any advice is greatly appreciated.

You described exactly how my '78 was behaving last year. Replacing the transducer cured it.