hmmm smoke is never a good thing with a speedo. If i were you I would disconnect the power and open up the speedo to make sure nothing has been shorted inside it. When it comes to wiring up a robot for the first time I know that the temptation is to do it quickly and tell yourself that you will do it properly next time. A lesson I learned a long time ago, if it's worth doing then do it right first time!

I think the running for a few seconds is an inherent thing with the spektrum gear. Never had it with futaba 40 meg radio equipment but occasionally get it with the spektrum. I guess it's a small reminder to treat the machine, what ever size, with the utmost respect when it comes to arming up and operating.