Note
Concord catalog 4-46 (1946), p. 107.
QST, Feb 1946, p. 4.
Lafayette catalog number 88 (1947), p. 100.
QST, Mar 1947, p. 5. (S-40A)
Concord catalog 9-47, p. 161.
Lafayette-Concord (1949 #949), inside back cover.
Allied Radio catalog 1951 (copyright 1950), p. 135. (S-40B)
QST, Aug 1950, p. 4. (S-40B)
QST, May 1951, p. 7.
QST, Jul 1951, p. 86.
QST, Mar 1954, P. 123.
The Hallicrafters S-40 is a well-known general coverage communications receiver that was a staple in many a radio enthusiast's shack from the late 1940s into the 1950s. Designed as a more affordable alternative to the company's top-tier receivers, the S-40 (and its subsequent S-40A and S-40B variants) offered a lot of performance for the price.
Featuring a 9-tube single-conversion superheterodyne circuit, the S-40 covered a frequency range from the AM broadcast band up to 43 MHz. It was equipped with an electrical bandspread feature for easier tuning of the amateur radio bands, and beat-frequency oscillator (BFO) for CW and SSB reception. The S-40's distinctive backlit dial, with its green glow, was a stylish touch that made it a popular choice for both serious listeners and hobbyists. Its user-friendly layout and solid performance made it an excellent entry-level receiver for a new generation of shortwave listeners and aspiring amateur radio operators. The S-40 remains a popular model for collectors and restorers today, prized for its classic design and nostalgic appeal.
The S-40A, released in 1947, featured a few circuit changes, though the overall design remained the same. It still used a 9-tube circuit and covered the same frequency range.
The Hallicrafters S-40B, which was introduced in 1950, represents a further evolution and cost-optimization of the S-40 line. While it retained the general appearance and function of its predecessors, there were some notable differences.
A key change in the S-40B was a redesign of the circuit to use one fewer tube than the S-40 and S-40A. Hallicrafters achieved this by combining some functions into a single tube. There were also a couple of changes in the tube lineup. These changes, along with other minor tweaks, helped streamline production and reduce costs.
Cosmetically, there were also subtle differences. The front panel of the S-40B was a single piece, with the speaker grill and dial escutcheon stamped directly into the panel, as opposed to being separate pieces as they were on the earlier models. This was another cost-saving measure.
Despite these changes, the S-40B maintained the core features and performance that made the S-40 series popular. It had the same frequency coverage, electrical bandspread, BFO, and crystal filter. These receivers are still well-regarded by collectors for their classic looks and ability to deliver a satisfying shortwave listening experience.
Power options include the standard 120 VAC transformer, and the universal power transformer (S-40U / S-40AU)) for 120-240 VAC operation. Differences between the S-40 and S-40A are mostly cosmetic. The dial of the S-40 is white (usually yellowed with age), while the dial of the S-40A is green. There are likely some minor circuit changes as well. Optional S-meter is SM-40 (see photo and separate entry).
Features include a headphone jack, BFO, AVC, ANL, pitch, standby, mute, tone control (three position), a built-in speaker and connections for an external speaker, flywheel tuning, and an uncalibrated zero to 100 bandspread.
Caution: Transfomerless circuit.
References
Review: QST, Jul 1946, page 69.
S-40B reference: QST, Aug 1950, page 4.
Coverage: 540 kHz to 43 MHz
One RF stage, two IF stages
IF: 455 kHz
Modes: AM, CW
BFO
ANL
Bandspread
External S-meter (optional)
Built-in speaker
Power: 120 volts AC-DC, or 240 volts depending the the changeable ballast resistor.
Tubes (S-40) (9 total): (1) 6SG7, (1) 6SA7, (2) 6SK7, (1) 6F6, (1) 6H6, (1) 6J5, (1) 6SQ7, (1) 80
Tubes (S-40A) (9 total): (1) 6SG7, (1) 6SA7, (2) 6SK7, (1) 6H6, (1) 6J5, (1) 6SQ7, (1) 6FG6, (1) 5Y3
Tubes (S-40B) (8 total): (1) 6SG7, (1) 6SA7, (2) 6SK7, (1) 6H6, (1) 6SL7, (1) 6FG6, (1) 5Y3
