The SP600-JX receiver was introduced by Hammarlund around 1950 and was produced in a variety of similar models until 1972. The price of this receiver was $985 (in 1950 dollars) -- very expensive at the time. By 1956, a Very Low Frequency version (SP600-VLF) was selling for almost $2000.

This is a LARGE receiver, and has a very solid and expensive "feel" to its operation. The mechanical 50:1 reduction tuning drive is one of the smoothest ever built - and one of the smoothest I've ever used. The restoration of this receiver is difficult because of the rotary turret used to change coils. The band spread setup divides each frequency band in to approximately 6000 readable settings..