This circuit is so common but I cannot find any service data for this model. It has the 6K7 instead of the 6D6 and the 55B2 ballast. It has a 43 output tube, 6C6 RF Amp and 25Z5. So, just 4 tubes and a ballast. It's a hot chassis set. There is a listing in Slusser (formerly Bunis) for an 80B. This might be the set I'm looking for the service data for. Any circuit with these tubes and ballast would probably be fine. I think this came up before and was found to be the same as a Silvertone.