1983 Nissan Sentra Parking Brake light comes on when drivin

Electrical problem
1983 Nissan Sentra 4 cyl Front Wheel Drive Automatic 167K miles

Engine: E-16(S), 1597cc, Mfg 5/83:

I replaced the alternator last Sept because both the parking brake and batery lights came on and stayed on when driving. The alternator was bad.

But now, just the parking brake light comes on when driving and sometimes when idling.

Is this the alternator, again?

Thanks.

Les