Add to Cart Quick view National XCU-50 Crystal Calibrator for HRO-50 & HRO-60 Receivers MSRP: Now: $89.99 Was: This National XCU-50 Crystal Calibrator, is made for the HRO-50 & HRO-60 Receivers. This one looks to be in great shape. I do not have a receiver to test it in but these calibrators are reliable and is a simple circuit. It is being... MSRP: Now: $89.99 Was: Add to Cart Quick view Qty in Cart: 0 Quantity: Decrease Quantity: Increase Quantity: Price: MSRP: Now: $89.99 Was: Subtotal: Add to Cart