https://voyager.gsfc.nasa.gov/Library/DeepCommo_Chapter3--14... and https://core.ac.uk/download/pdf/42893533.pdf have some details. (https://ieeexplore.ieee.org/abstract/document/57695 likely does, too, but is paywalled)

What I don’t understand (possibly because I didn’t read them fully) is why they didn’t use the better one from the start and taped its data. Maybe they didn’t trust the Voyager to work yet? (One of those PDFs says this was an experimental system) or didn’t Voyager produce enough data to use its full bandwidth (further away, its signal got weaker, so it needed better error correction and/or better receivers on earth) when it still was relatively close to earth?