I receive broadcasts from Sudbury transmitter, which will not have the extended Freeview HD services (BBC4, BBC News, AlJazeera, CBeebies) although I can get BBC3 HD.

However, I can also pick up the Sandy Heath transmitter, which does have these services on ch 32.

Is it possible to manually tune for ch 32 on HDR T2 from Sandy Heath, whilst leaving all other channels picked up from Sudbury without causing any problems? Or are you forced to select only one transmitter or the other?

You should be able to tune signals from multiple transmitters, but many Freeview boxes (I can't speak for the T2 from personal experience) will put stations that are not from the 'primary' transmitter into the programme list starting at 800. You may find that you'll have BBC4 SD on a low channel number, and HD at channel 8xx

Provided you have adequate reception of Sandy Heath then it is perfectly possible to manually tune the T2 to it.

As the channels don't clash with any already tuned in it should put them on the correct channel numbers. It only puts duplicates up in the 800s

You can manually tune as others have said. However recordings for channels from Sudbury set using accurate recording may fail when you are watching (or recording?) anything from Sandy Heath. You can switch to using a padding strategy by changing recording start time and/or end time to something other than "On time".

Thanks Martin. Is that a definite outcome (i.e. it cannot read from 2 transmitters for AR recording at the same time, but can on ordinary padded recordings)?

Is manually tuning for just one channel band straightforward with the T2...never done it before!

The behaviour will be erratic when using accurate recording with two transmitters as it will depend on what is being watched live, what is being recorded and what is scheduled to record in the immediate future. Padding should work fine. There are a number of users on the Northern Ireland/Irish Republic border who want to have programs from both sides of the border and they use a padding strategy.

Yes. If you are trying to tune an HD multiplex remember to change the transmission type from DVB to DVB-T2.