Sujet : Re: C128 and C64 OS
De : fake (at) *nospam* ddress.no (Robert Roland)
Groupes : comp.sys.cbmDate : 20. Aug 2024, 11:36:43
Autres entêtes
Organisation : A noiseless patient Spider
Message-ID : <d7s8cj5ugvb08s4vkh96akf1t0ffv90up4@4ax.com>
References : 1 2 3 4 5
User-Agent : Forte Agent 4.2/32.1117
On Tue, 20 Aug 2024 00:38:38 +0100, Adam Sampson <
ats@offog.org>
wrote:
Having dismantled it, the reason was that it uses a 7805 regulator with
a resistor divider to lift its ground reference pin a bit, and the
resistor values had drifted considerably.
I have been thinking about various failure modes that could possibly
cause an overvoltage condition. This is the only one I have been able
to think up. Thank you for confirming.
Not all versions use these voltage boosting resistors, though, so the
myth that all of them will fail, is still on thin ice as far as I am
concerned.
-- RoRo