1977 911 Targa electrics

[keith912]

Hi, just got back from the Ace Café Porsche night and think my alternator has gone or maybe something else?

On the way there the red gen light came on so pulled over and checked belt, all good. Carried onto the Ace in the snow thinking am I mad, when I got there and turned the car off the red light stayed on and if I turned the ignition key to on the light went out (strange). Disconnected battery until I wanted to leave. Connected it back up and started the car to come home, gen light stayed off then came on about 5 mins later. Power gradually died until I got home with flat battery. Engine was revving a bit high when I got home and also noticed tacho needle was bouncing from 2000 to 4000 independent of engine revs and then died all together (while driving along at 70mph).

Am I looking at alternator for sure, or ignition or battery?

Any advice greatly appreciated!

Cheers

Keith