The AN/ARC-5 R-26 and R-27s with the Spot-Tuner attachments were specifically designed for use with the ART-13. How well they worked, I don't know. Will try it out one day. D.S. William Donzelli wrote: >>The USN never did have a receiver that matched the capability of the ART-13 >>until the ARR-15 came along post war.