'68 Catalina electrical issues

[donrolfo]

Hey guys,
on my 68 Catalina I seem to have some electrical issues, but not sure where they come from and how to fix. Here are the symptoms:

Not working:
- Radio stays at extremely low volume (not completely dead, but like the amp is dead)
- headlights not working, only parking light (even with engine running). However parking light will flicker depending on engine revs, even in idle mode. Nothing changes when the light knob is fully pulled (no high beam).
- all interior lights not working, including dashboard light
- fan for the A/C / heating not running
- basically all dashboard gauges are not moving, except speedometer
- clock

Working:
- convertible top
- brake lamp and oil lamp in dashboard
- wipers (running also when engine is off - not sure if that is intended, at least somehow I managed to switch them on over night and they killed my battery )
- washer pump (although running dry, so not tested for long)
- tail lights
- flashers (but the interval is not constant, more like "tic toc tictoctictoc tic toc") and flasher indicators in dashboard

My ideas are either the alternator has some issues or some ground issues. But honestly no idea where the relevant ground strips are located for a check...

 

[melsg5]

could be an internal problem with the radio, volume pontentiometer
pulling the headlight switch all the way out does NOT turn on the highbeams, there is a switch on the floor next to your left foot.
have you tested whether you are getting power to the headlights with a voltmeter or test light?
have you looked for blow fuses or fuses with poor contact in the fuse box?
if the fan does not work on all speeds try applying power directly to the fan motor