How little sun can I get away with for autumn raspberries?

[SumAndSubstance]

We have quite a big garden, surrounded by a tall wooden fence, so it's quite sheltered inside. The problem is that much of it is North-facing so it gets very little sun. I used to have an allotment and grow raspberries and would love to try growing some here, but I worry that they won't do well without a good amount of direct sun. Can anyone offer any hope that they might grow?!

I have them growing in the far NE facing corner of the garden, and I get sweet berries from them, as did my neighbour who had them in the equivalent spot in her garden. They are gradually spreading into the sun, but I dig 'em up and replant.

I have some in my back garden, which only get two or three hours of sun in the middle of the year. They do produce but not much, and not a patch on the ones which I moved round to the front of the house in full sun. The berries which appear later in the year are pretty feeble and don't turn red. I'm moving them into full sun at a new allotment shortly.