Electrical issue on an old Triumph, any dynamo specialists?

[BIRMA]

My 1955 Triumph is running like a dream but I've got an issue with the lights so much so I had to ride for 30 minutes along very dark country lanes to get home with lights fading to nothing. I have now bought a CTEK 6 volt conditioner and fitted an on/off switch so as to not drain the battery which I think is happening. The other very noticeable thing is that when on tick over the lights are fine but get dimmer when I rev it up. I am sure the old dynamo is fine but wonder if these are the symptoms of the wires to the dynamo being the wrong way round. The ammeter goes right over to max charge despite the battery being correctly fully charged/conditioned.
I'm not an expert with electrics but have a basic understanding but this problem is a bit beyond me.

[BIRMA]

gareth_r said:

Is V-O still trading?

http://matchlessclueless.com/electrical/lucas/test...

http://matchlessclueless.com/electrical/lucas/repo...

Other guides are available.

Thanks that's just what I was looking for.

[BIRMA]

Hooli said:

Sounds like the voltage regulator isn't doing it's job.

Thanks,
On the above guides it states that the polarity of the dynamo can be reversed if not used for a while and wonder if that may be the case.