Charging,?.

[David.H]

A bit of success, but more questions than answers
The dynamo turns out to be a type C35M  220298 (So Late Ruby ?) Rebuilt post war as the pole screws are Phillips drive, not slotted! , the cut out is a CF (no suffix number).
The cut out is not operating ...Checking the cut out with a decent meter the readings were 370k (tiny) not 60 ohms...conclusion voltage coil is dead! I don't think the CF is particularly compatible with the C35M (which may or may not have a functioning resistance and would usually have been mated with a CFR/ CFR2.
What to do? 
Have the CF rewound (by who?) and put a resistance wire between the dynamo terminals.  
Find a CFR /CFR2?
Does the lingering doubt about the switchboard (probably no functioning resistance from Winter to Summer) matter?
Just drive on the battery (Good short term solution!) and see how the engine feels after a bit of use!!

Thanks for continuing advice...one thing I have learnt...find out what EXACTLY you have got and take accurate readings
I think my brain hurts! I am at one with John P and his starter!