Can someone explain to me how the ARC-5/SCR-274 navigation receivers were used. There must have been a loop antenna and ADF display that were not an actual part of the ARC-5/SCR-274 components. I'd also like to find documentation on the ARN-6 and ARN-7 radios. Bob Macklin K5MYJ Seattle, Wa. "Real Radios Glow In The Dark"