23 Jul
2012
23 Jul
'12
12:18 a.m.
Paul Anderson wrote:
I checked out the power supply. It's basically a
common-base amplifier with a 5.6v Zener diode. It doesn't have a full-wave bridge
rectifier. Theres a 4,000uf electrolytic capacitor for filtering the input to the
transistor. Given the design, I'd expect it to be pretty sensitive to problems with
that capacitor. If I have a suitable part, I think I will replace the transistor and the
diode with a proper 7805 regulator.
I'd recommend keeping it as original as possible. If the capacitor is
good it should regulate fine, and if the capacitor is bad, it needs to
be replaced.