How do I manually input the range to target into the TDC?

[Able72]

I can use the stedimeter, great when you can see and ID your target.

If you can't? because of weather conditions etc.

I can get the range, from surface radar or by pinging with sonar (and sonar lets me send the range directly to the TDC so I guess this primarily applies to RADAR), but I can't figure out how to input that information. Otherwise I'd have been able to calculate a firing solution on this one merchant at a range of 15.1 nm. I estimated speed at 11kts and AOB was 4*. Thats everything you need to have a firing solution. I just couldn't figure out how to input the range.