Well just some comments that may help you track down your problem.I'm no expert and offer this as just suggestions and comments
and if anyone see's something thats not right steep in and give your addvice.

First Batterys==== I see a lot of posts here on the forum about batterys and chargers.Over all the ones that come with the tanks and their chargers will operate your tank.Are they great battery's and chargers(they do what they were intended to do).I have yet to get a stock battery that would not run a tank for at least 15 minutes or longer on a short charge for testing(not even a full charge).
If you are going for long run times and indurrance running then you can do what ever as this is not a factor at this point.
Transmitter battery's,if you get a nice red light on the transmitter the batterys are most likely doing their job and it will work great.
Even a weak battery should start your tank,it takes very little power to at least run the sound.(is it good to try and run your tank on a very low charged battery???? Most likely not.!!!)But this is most likely not the reason the tank will not at least start up and the lights
will stop flashing and you will get the start up sound.

If the lights are flashing on the tank,you have a nice bright red light on the transmitter and you push the start button and NOTHING I think you can rule out batterys.Your problem is elsewhere.????

Crystals==== With out a proper compattable working matched set of crystals you are going nowhere.I don't know how to test these other than have another working tank and by swapping them out and test them.I change out both the transmitter and receiver
first to see if the tank will now work with a crystal swap.(don't just swap them out one at a time,do them both at the same time).If this cures the problem I would not try to determin which crystal is bad because they are sold in sets anyway and I would not want to try and salvage a crystal from a bad set.

If you have another( known working tank) with a (known working transmitter) and (known working crystals)and you have changed the crystals and used the working transmitter and it still will not fire up (just blinking lights,no start up),You should then be able to rule out a BAD==== Transmitter or crystal set.

Now where does that leave you at this point ???

THE BOARDS===== If the lights are FLASHING,you know power is getting (at least to the big board).The little board gets its power by way of the three wire jumper between the two boards.Where you had allready run your tank prior to having a problem I would assume this jumper is in working condition(but I would use a tester on each wire to make sure of contanuity on each one).If this jumper proves to be good then comes the question == ARE THE BOARDS BOTH IN WORKING ORDER====
Myself I know nothing about boards and how one can test them,other than changing them out with another set.(I have received new boards that were also defective)???? These boards are sold as sets and I would never buy a new set and try to inter change a board from a tank you were having problems with with a new set. (change out the SET,don't just do them one at a time).I have had them FRY for no appearent reason just after turning on the tank,so don't take the chance of burning up a new board by replacing just one board at a time.(WHICH BOARD MADE IT FRY, ???? I have never figured this out so I don't take the chance on a new board by not changing them out as a set).

Hope this in some way will help you find your problem. REGUARDS and best of luck BIGMIG


P.S. when the lights flash and you get nothing from the start button I always lean towards ( CRYSTAL PROBLEMS).This has happened to me on several occassions. BIGMIG [:-]