National NC-88 "World Master"
National NC-88 "World Master"
The National NC-88 "World Master" is a general coverage single conversion 9 tube receiver. Tuning range is 540 KHz to 40 MHz in 4 bands. The bandspead scale is marked for the ham bands. There is also an SWL version, the NC-88SW, that has the bandspread marked for popular short-wave listening bands. Other than markings, they are identical. Either set makes a decent SWL receiver. The set has a tuned RF stage, two IF stages, a separate HF oscillator tube, and a built-in speaker. Priced at $119.95 in several introductory ads in the August 1953 QST. The NC-98 is a similar receiver introduced a few months later. It adds an S-meter and crystal filter and requires an external speaker. The NC-98 was reviewed in the August 1954 issue of QST.
Repair note: I bought this receiver at an antique radio swap meet. The former owner had been unable to repair it. Through voltage checks, found that one of the 6BD6 IF tubes had serious grid emission blocking the AVC-controlled stages. This was one of the rare instances where a tube was totally at fault and also where the typical emissions-type tube tester would not be able identify the problem tube.