Depends on where you live. Here in Germany

I'm from Germany but live in the US (until next month). I'd like to have the tuner done before I move back...

If you can measure resistance, test the tree solderpoints for shorts. There is a chance of having a defective 7809, but this happens only once in a blue moon. Don't count on this.

It worked fine on the previous test I made (a few steps back). I'll try to see if I can find something. Any more tips are dearly appreciated!
Thanks a million!