Can disks be copied using only one RL02 drive?

[charlesmorris at hughes.net]

I've got a PDP-11/23+ with 4 Mb RAM, but only one RL02 and no software 
except an XXDP pack. Henk Gooijen helpfully made for me a (RT-11) 
bootable pack that is on the way (if the post offices between Europe 
and the US don't lose or destroy it). So I definitely want to make a 
backup copy.

Is this possible to do with only one drive? Apparently you can't swap 
disks back and forth like the old DOS or CP/M systems. Henk thinks 
creating a RAM disk would work, and copy files but I don't know 
anything about RT-11.

The alternative is to take the RL02 from my PDP-8/A and connect it, 
but then I don't have a "1" key, they are both unit "0".

Any thoughts?
thanks
Charles