Collins 32S-3 — Serial Number & Production Guide
VK6ADA Technical Reference · Collins S-Line Vintage Amateur Equipment · March 2026 · Mike Peace VK6ADA
The Collins 32S-3 SSB Transmitter is the definitive and most produced model of the S-Line transmitter series, manufactured from approximately 1964 through the mid-to-late 1970s at the Cedar Rapids, Iowa facility.[1] Companion to the Collins 75S-3 receiver, the 32S-3 was in continuous production long enough to span all three Collins emblem eras — making the front-panel badge an especially useful dating tool. This guide consolidates serial number ranges, emblem transitions, manual edition history, and known circuit variations to help collectors and restorers authenticate and date their units.
Overview & Specifications
Manufacturer | Collins Radio Company — Cedar Rapids Division, Cedar Rapids, Iowa |
Model Number | 32S-3 (Collins type designation: SSB Transmitter) |
Production Period | ~1964 – approximately 1977–1979 |
RF Power Output | 100 W PEP SSB / 100 W CW |
Frequency Coverage | 3.5–4.0 MHz (80m), 7.0–7.5 MHz (40m), 14.0–14.5 MHz (20m), 21.0–21.5 MHz (15m), 28.0–29.0 MHz (10m) |
PA Tubes | 2 × 6146A / 6146B (parallel pair, pi-network output) |
Modes | USB, LSB, CW |
Carrier Suppression | ≥ 50 dB below PEP output |
Unwanted Sideband Suppr. | ≥ 50 dB below PEP output |
Mains Supply | 115 V AC or 230 V AC, 60 Hz single-phase (primary wiring selectable) |
Companion Receiver | Collins 75S-3 / 75S-3B / 75S-3C |
Companion Amplifier | Collins 30L-1 Linear Amplifier |
Introduced | ~1964 [10] |
Collector Status | Most common S-Line transmitter — Winged Emblem examples most desirable to purists. |
Important Note on Serial Number Sequencing
Per CCA historical research and a direct account from a former Collins employee,[9] Art Collins decreed that S-Line serial numbers were to be issued in random (non-sequential) order to prevent price discrimination among model variants. A lower serial number does not necessarily indicate an earlier production date. For the 32S-3, with its 15+ year production run, the emblem type is the most reliable single dating indicator and should always be checked before consulting serial number ranges.
Collins Logo / Emblem Production Eras
The 32S-3’s long production run means it is the only S-Line transmitter to appear with all emblem types. The emblem is the single most reliable quick-dating indicator for the 32S-3.[3]
| Emblem Type | Production Period | Approx. S/N Range | Physical Description | Collector Notes |
|---|---|---|---|---|
| Winged Emblem | 1964 – Fall 1969 [3] | ~101 – ~12,000 (approx. upper boundary) | Classic silver-and-blue winged Collins insignia. Two mounting holes either side if badge was replaced. | Most desirable to collectors. Five-year production window. Verify with internal 1964–1969 component date codes. |
| Round Emblem Transition | Fall 1969 only [3] | ~11,000 – ~13,500 (overlap zone) | Round “meatball” emblem plus two small grey screws plugging former winged-emblem holes. | Least common 32S-3 variant. Grey screws are the definitive identifier. Extremely rare and collectible in its own right. |
| Small Round Emblem | Fall 1969 – ~1975 [3] | ~12,000 – ~25,000 (approx.) | Circular Collins emblem approximately dime-sized (~18 mm diam.). No flanking screw holes. Single central attachment. | Post-Rockwell acquisition era. Circuit design essentially unchanged from late Winged Emblem production. |
| Large Round Emblem | ~1974 – FY1976/1979 [3] | ~23,000 – ~35,000+ (approx.) | Round Collins emblem approximately nickel-sized (~21 mm diam.). Slightly bolder typeface. | Late Rockwell-Collins era. Last production 32S-3 units. S/N range extends to highest documented 32S-3 numbers. |
Note: S/N boundaries are derived from CCA S-Line Production Surveys by Rod Blocksome K0DAS[4] and community-documented data. Individual serial numbers were randomly assigned — overlap between eras is expected.
Serial Number Lookup Reference
Quick Era Identifier — Enter Your Serial Number
Documented Serial Number Data Points
| Serial Number | Emblem / Era | Notable Features | Source / Reference |
|---|---|---|---|
| ~2,xxx range | Winged | Early 32S-3 production; consistent with 1964–1966. Original 6146A PA tubes. Companion 75S-3 serials of similar era are sought to create matched stations. | CCA S-Line survey data [4] |
| ~7,xxx – 10,xxx range | Winged | Mid Winged era; c.1967–1969. Most commonly encountered Winged Emblem 32S-3 range. Component date codes typically confirm late 1960s manufacture. | CCA survey / QRZ community [4][7] |
| ~12,xxx – 13,xxx range | Transition Zone | Emblem transition overlap zone — physical inspection essential. Some units in this range carry transition (grey-screw) or early Small Round Emblem. | CCA survey / community observation [4] |
| ~16,xxx – 22,xxx range | Small Round | Post-transition production; c.1970–1974. Small Round Emblem (~18mm). Rockwell acquisition era. Circuit unchanged from late Winged production. | Collector community / eBay documented sales [7] |
| ~28,xxx+ range | Large Round | Late Rockwell-Collins production; c.1975–1979. Large Round Emblem (~21mm). Final production era 32S-3 units. | Collector community / CCA survey [4] |
Manual Edition History
| Edition | Date | Collins Part Number | Notes |
|---|---|---|---|
| 1st Edition | ~1964 | — | Original publication with initial production units. Archived at CRA: collinsradio.org.[1] |
| ~2nd–4th Editions | 1965–1969 | Various | Progressive service bulletin amendments. Available via CRA archive and worldradiohistory.com. |
| Final Edition(s) | Post-1969 | — | Final revisions incorporating all service letter amendments to date of publication. CRA PDF archive recommended.[2] |
Circuit Variations by Production Era
| Change Description | Component(s) Affected | Era Indicator |
|---|---|---|
| PA tube type standardisation | V (PA pair) | 6146A standard from introduction. 6146B approved as equivalent substitute in service bulletins. Specify matched pair on replacement. |
| ALC loop refinement | ALC components | Service bulletins addressed ALC stability and drive levels during production lifetime. Later manuals incorporate all amendments. |
| HV rectifier specification | HV rectifiers | Progressive improvement from early silicon to higher-PIV types. Replace all with 1N4007 equivalents on restoration regardless of era. |
| Screen voltage regulation | Screen supply components | Minor screen circuit refinements appear in mid-production service bulletins. Check manual edition for applicable amendments. |
| Physical emblem change | Front panel badge | Winged → Transition Round → Small Round → Large Round over the production span. Most reliable single era indicator. |
Physical Identification Guide
Step 1 — Front Panel Emblem
- Winged Emblem: 1964 – Fall 1969. Most desirable to collectors.
- Round Emblem with flanking grey screws: Transition unit, Fall 1969 only. Extremely rare.[3]
- Small Round Emblem (~18 mm, dime-sized): Post-Fall 1969 to approximately 1974–1975.
- Large Round Emblem (~21 mm, nickel-sized): Mid-1970s through final production (~1979).
Step 2 — Serial Number Plate
Located on the rear panel. Plain integer format — no alphabetic prefix or suffix. Cross-reference with the range estimates above, noting that random S/N assignment means overlap at era boundaries is normal.[9]
Step 3 — Internal Component Date Codes
Electrolytic capacitors carry date codes in format YY WW (year / week). The latest date code on original components establishes the earliest possible ship date. Cross-referencing internal date codes with the emblem type is the most reliable dating method available.
Step 4 — Manual Edition Check
Copyright dates of 1964–1966 only: early production. Copyright dates extending into the early 1970s indicate mid-to-late production. Manual editions covering 32S-3 are distinct from 32S-1 and 32S-2 editions.
Step 5 — Distinguishing 32S-3 from 32S-3A
Some documentation references a “32S-3A” variant reflecting internal changes introduced at a mid-production service bulletin. These are generally not visually distinguished from the 32S-3 on the front panel. Check the rear serial plate for any variant suffix and cross-reference with the applicable instruction book edition.
Typical Restoration Considerations by Era
| Component | All Eras — Recommended Action | Winged Era Notes | Round Emblem Era Notes |
|---|---|---|---|
| HV Filter Capacitors | Reform or replace as first priority | Original electrolytics; 55–60+ years old. Reform carefully; replace if any doubt. | Same recommendation; caps may differ in physical packaging. |
| HV Rectifiers | Replace with 1N4007 or equivalent | May have early silicon types — replace regardless. | Likely later silicon from factory; verify PIV rating and replace. |
| PA Tubes (6146A/B pair) | Test and match; 6146B recommended | Original 6146A often present. Matched pair critical. | May already have 6146B from later factory supply; verify. |
| PTO Stability | Verify alignment and drift | Precision Collins mechanical assembly. Allow 30+ min warm-up before drift testing. | Same recommendation. |
| ALC Calibration | Verify per manual procedure | ALC threshold may drift after decades. Calibrate with power meter. | Same recommendation; check applicable service bulletin amendments. |
| Mechanical Filters | Test insertion loss; seldom fail | Collins mechanical filters are extremely reliable. Replace only on confirmed failure. | Same. |
This guide consolidates publicly available CCA survey data, community restoration reports, and documented sale records. Serial number range estimates should be treated as approximations. Contributions and corrections are welcome via vk6ada.com.au or through the Collins community at r-390a.net.
References, Citations & Credits
- Collins Radio Company. 32S-3 Transmitter Instruction Book. Cedar Rapids Division, Cedar Rapids, Iowa. Various editions ~1964–1975. Archived by the CRA: collinsradio.org — Technical Archives
- Collins Radio Company. 32S-3 Transmitter Instruction Book, final edition. CRA archive: collinsradio.org
- Blocksome, Rod K0DAS. “The Collins S-Line Logo and Emblem Transition History.” CCA Historical Archives. 2013–2016. collinsradio.org — Historical Archives
- Blocksome, Rod K0DAS. Collins S-Line Transmitter Production Surveys. CCA Technical Archives. Various years. collinsradio.org — Blocksome Surveys
- Collins Radio Association. Collins Radio Technical Archives. collinsradio.org
- WA3KEY Virtual Collins Radio Museum. Collins 32S-3 Reference Pages. wa3key.com. Accessed 2026.
- QRZ Forums — multiple threads documenting Collins 32S-3 serial numbers, restoration notes, and emblem eras. forums.qrz.com. Accessed 2026.
- Collins Collectors Association FAQ. Biographical notes on Collins Radio engineers. WA3KEY: wa3key.com/ccafaq.html. Accessed 2026.
- Anonymous (attributed to a former Collins employee; reported by Roger KB4THL). “[Collins] Winged versus Round Emblems.” QTH.net Collins Reflector, July 2005. qth.net — July 2005
- QST Magazine — Collins Radio advertisement, 32S-3 SSB Transmitter, ARRL, ~1964. QST archive: worldradiohistory.com
- Peace, Mike VK6ADA (Administrator). r-390a.net. r-390a.net.
- Peace, Mike VK6ADA. vk6ada.com.au — Collins S-Line Reference. vk6ada.com.au/collins-collection/. 2025–2026.