13-14v at the battery at idle is just fine, and it is the dynamo or
alternator that is supplying the load when the engine is running and not the
battery (which is receiving energy i.e. charging). I don't know what the
internally regulated voltage of the radio is but if it is a relatively
modern electronic unit I would expect it to be internally regulated down to
something less than the supply voltage precisely so that supply voltage
differences do not affect output.
Are you sure you aren't listening to heavy metal music and with all the
valve clatter and exhaust noise at speed it only seems louder???
----- Original Message -----
From: Tony Woodruff <tonyw@mailmedia.com>
To: <mgs@autox.team.net>
Sent: Wednesday, April 19, 2000 5:35 PM
Subject: Dynamo / Generator Question
> My 67 (actually mid-66) MGB roadster has the stock positive ground /
dynamo set up.
>
> Is it normal that at idle my radio, etc. should be "starving" for
electricity - or is this a sign of a failing unit? The radio gets really
quiet and won't pull in a signal at all unless the engine revs are up around
2000 RPM.
>
> At speed the battery is getting plenty of current to keep itself charged
up. At idle I see 13-14 volts across the terminals - so it looks OK from
that perspective.
>
> The thing is that at the times I'm waiting at a stop light - and not
enjoying the thrill of moving about in my LBC - the darn radio won't work!
(of course it doesn't work very well ever.....)
>
>
>
>
|