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 personally ever used. No weighted knob on a digital rotary contoller even comes close to the feel of this tuning mechanism. The receiver covers 540 Khz to 54 Mhz in six bands with a complement of 20 vacuum tubes. Its weight is listed at 100 lbs. It is probably the ultimate design for the genre of receivers utilizing a tunable first conversion oscillator.
The SP600-JX-17 is distinguishable from other models by the two small red controls right under the dial windows. It was specifically designed to be slaved to a second receiver for dual diversity operation.
SP600 models were produced in large quantites and were used by the military, the FBI, the CIA, and other government and commercial organizations. As a Ham Band receiver, it works well on 160-20 meters, but suffers from lack of adequate bandspread on the higher bands -- not surprising since the SP600 was not specifically designed with Amateur Radio in mind. This one stays pretty well glued to 160-80/75 meters where there is a lot of nighttime AM activity, and is used regularly for general HF Shortwave Listening where it excels.
My receiver has been completely refurbished inside and out. It performs
well and looks like it was just removed from its factory packing.
I got free a Brand New in the box cabinet to house my SP600, only caveaut, it is "Yellow"!
Jim WB2FCN, here it is in the operating position:
