Radio lights up but....no sound? Fuses good, and am going to check it out with a test light but is this a common issue just bought last week and haven't had time to work on much. Just slapped a $10 antenna on it to drive it to work could that be an issue?

In my experience with the '78 OEM Datsun AM/FM stereo radio, the antenna makes a huge difference in reception (or lack thereof).

With the stereo button pushed in, does the stereo light ever come on when you scroll the tuner through the FM band?

I read some where that you have to tune the radio to the antanna. There is a screw in the back.

I read some where that you have to tune the radio to the antanna. There is a screw in the back.

That's the 'antenna trimmer' adjustment. From what I understand that only applies to AM. Something else is likely wrong because even without an antenna, you should get some kind of sound like hissing, crackle, etc.

according to the wiring diagram there should be another black wire and the blue should be another place in the connector but i don't she how or why it would be like it is.