Note
QST, Feb 1948, p. 103.
Lafayette-Concord catalog "1948 Christmas Book," p. 34.
Lafayette-Concord (1949 #949), p. 143.
Allied Radio catalog 1951 (copyright 1950), p. 135.
QST, Aug 1950, p. 73.(S-53A)
QST, Aug 1954, p. 136 (S-53A)
The Hallicrafters S-53(A) is a classic vintage communications receiver that was produced from 1950 to 1957. Designed as a step-up from the popular S-38 series, the S-53(A) offered improved performance and features in a compact, attractive package. It was an eight-tube, single-conversion superheterodyne design using a mix of glass, metal, and miniature tubes.
The S-53(A) featured a built-in speaker, with a silver and grey metal cabinet that exuded a professional feel.
While it was well-regarded for its sensitivity and fidelity on AM signals, the S-53(A) was not ideal for single sideband reception due to its fixed-pitch BFO and lack of an RF amplifier. However, for shortwave listening and general coverage reception, it was considered a great value, making it a popular choice for hobbyists and collectors on a budget.
Single conversion superheterodyne. Features include “sensitivity” control (RF gain, with a position for PHONO input), AF gain, ANL, a headphone jack, standby, built-in speaker, zero to 100 bandspread, two position tone control, a speaker/phones switch (on the rear panel).and a phono input jack.
Acoording to Dachis, two versions of the S-53 were made. The first had a top that was entirely perforated, and had a bright quilted metal escutcheon. The second had a solid top, perforated only above the speaker, and a smooth escutcheon. The S-53A uses the second type.
Both the S-53 and S-53A have a gap in their frequency coverage between about 1.6 and 2.6 MHz. This is because the of the IF frequency engineers used. Receivers can not effectively receive frequencies below their IF frequency.
Prioritizing shortwave reception over AM broadcast, engineers chose an IF 2075 kHz for the S-53, because that frequency would improve image rejection on all higher frequencies. The tradeoff was that it would limit AM broadcast reception to only strong local signals. Still, AM broadcast reception was considered important enough that even though it was hobbled, it would be retained. But the essentially unusable segment from 1.6 to 2.6 MHz would be deleted, as there wasn't much there to listen to in the first place.
Hallicrafters lived with this compromise for a couple of years before deciding on a redesign to improve AM reception.
In the S-53A, they chose 455 kHz (just below the AM broadcast band of 550 to 1600 kHz) as the new IF. This would greatly improve AM broadcast reception, but it would cause images of AM stations (kind of like ghost signals) to appear about one megahertz higher–between about 1.6 and 2.6 MHz because the radio lacked a tuned RF stage to suppress them.
To solve that problem, engineers simply decided (again) to leave out that segment of frequencies entirely, reasoning that most listeners would not be missing very much anyway.
Freq. coverage: 540 to 1630 kHz; 2.6 to 31 MHz; 48 to 55 MHz.
IF: S-53, 2075 kHz
IF S-53A, 455 kHz
2 IF stages
Modes: AM, CW
Built-in speaker
Bandspread
Audio output: 1 watt, 3.2 Ω
Power:
S-53(A): 120 VAC, 50 watts
S-53U:
Tubes: (1) 5Y3, (1) 6K6, (1) 6SC7, (1) 6H6, (1) 6C4, (3) 6BA6
