Fisher FM-50 FM Tuner (1959)

Name: Fisher FM-50
Brand: Fisher

Three microvolts of quieting, six tubes, and a multiplex jack for a stereo future that hadn't been invented yet.

Overview

The Fisher FM-50 arrived in 1959 as one of Fisher Radio Corporation's early dedicated FM tuners. It was a single-purpose box with no amplifier inside, built to feed a separate preamp and power amp. You bought a tuner, a preamp and an amp, and you assembled a system instead of a console. Fisher's own advertising that year pitched the FM-50 as the "quality FM tuner at moderate cost." It listed at $129.50, against the $229.50 flagship FM-200 and the $229.50 X-202 control amplifier it was meant to sit beside. The company made that price ladder very clear in its magazine spreads.

The FM-50 isn't interesting today for raw performance. It's interesting for the timing. The tuner was engineered for listeners chasing static-free FM at a moment when FM was still gaining traction in American homes. It shipped with a multiplex output jack that let it interface with external stereo decoders, and those decoders wouldn't have a standard to decode until the FCC approved FM stereo multiplex in April 1961. So Fisher was selling a stereo-ready tuner before stereo FM existed. High Fidelity (September 1961, p.15) ran Fisher's own copy claiming the FM-50-B led its field with the exclusive "Stereo Beam," the company's signal-strength indicator invention, and the ad framed the tuner as one that no other unit of its type could match for quality and flexibility. That's advertising, not an independent verdict.

A naming caution first. The fact sheet's sources use "FM-50" and "FM-50-B" inconsistently, and no source explicitly states the relationship between the two. Some eBay listings in the record refer to an "FM-50B" or "FM-50-B," and the period magazine chunks from 1961 through 1964 consistently advertise an "FM-50-B" at $199.50. Whether that's a later revision of the same tuner or a distinct variant is not documented here. Treat any spec attributed to the "-B" with that uncertainty in mind.

Key Features

Six Tubes and a 3 μV Sensitivity Rating

The FM-50 runs on six vacuum tubes: 6AU6, 6BA6, 6BE6, 12AT7, 12AU7, and an OA2 voltage regulator. The 6BA6 and 12AT7 sit in the RF and IF stages, and the fact sheet credits those two specifically with the tuner's low-noise amplification and smooth signal handling. Sensitivity is rated at approximately 3 μV for 20 dB of quieting. That's a single-source figure, so hedge it, but it's a workable number for a 1959 tube tuner feeding a decent antenna. The OA2 regulator stabilizes the B+ supply. When one of these tuners misbehaves, that tube and its associated components are where a restorer looks first.

AFC Switch with Manual Override

Automatic Frequency Control is on board. The AFC switch locks the tuner onto a station and fights thermal drift, but it can be disengaged for fine manual tuning. Early FM tuners drifted, and AFC was the fix. A locked AFC circuit also fights the tuning knob, which is why Fisher gave users the option to switch it off.

Multiplex Output for a Stereo Future

The rear-panel multiplex output is the FM-50's most forward-looking feature. When the tuner shipped in 1959, there was no FM stereo standard, and the fact sheet notes the official adoption of stereo FM began in 1961. Fisher included the MPX output anyway, so the FM-50 could feed an external decoder once one existed. The Fisher MPX-100 adapter's own owner instructions list the FM-50 as a supported tuner, with both MAIN and REC outputs connected to the adapter and the tuner's own separation control set for the MPX handoff.

Slide-Rule Dial and Analog Tuning Meter

Tuning is by slide-rule dial with an analog meter for signal strength and center-of-channel alignment. The FM-50's period advertising leaned on the "MicroRay tuning indicator" as the tool for precise FM tuning and tape recorder level indication. That's Fisher's marketing language for what amounts to a well-lit analog meter. No digital readout, no presets, no memory. A dial, a needle, and tubes warming up.

Brushed Aluminum Front Panel

The FM-50 wears a brushed aluminum front panel with black cabinet accents, and it measures 19 inches wide by 7 inches high by 10.5 inches deep. The width is standard rack-adjacent component sizing for the era, so the FM-50 sits naturally alongside Fisher's own preamps and amplifiers of the period. Output impedance is estimated at 600 ohms, a typical figure for tube equipment of this vintage, and the fact sheet flags it as an estimate rather than a measured value.

Historical Context

Fisher Radio Corporation, founded by Avery Fisher, positioned itself in the late 1950s as a leader in high-end audio. The FM-50 was one of its early dedicated FM tuners, a component built for listeners who wanted FM's static-free transmission and superior fidelity to AM, and who were willing to assemble a system rather than buy a console. The tuner predates the official adoption of stereo FM broadcasting, which the fact sheet places at 1961. The multiplex output is the clearest evidence that Fisher was already thinking past mono when the FM-50 went on sale.

Fisher's competitors at the time included Marantz and Scott, both named in the fact sheet as contemporaneous competitors. The FM-50 was not as rare as some of their models, and it wasn't priced to compete at the top of the market. Fisher's own 1959 advertising placed it at $129.50, well below the $229.50 FM-200 in the same catalog. It was the accessible entry into Fisher's FM lineup, not the flagship.

Collectibility & Value

The FM-50 carries a collectibility rating of 6 out of 10, and fully restored units in excellent cosmetic and functional condition typically sell for $100 to $250. Recent eBay listings in the record show a serviced example at $144 and an untested one at $130, which brackets the lower end of that range. Units with original packaging, manuals, or service literature may command higher prices. A SAMS Photofact service manual is available for the model, listed at $15.00.

Restoration is not optional on a 1959 tube tuner. All electrolytic and paper capacitors should be replaced, because old capacitors leak, short, or degrade performance. Carbon composition resistors may have drifted in value and should be checked. The 6BE6 and 12AT7 are called out as particularly critical for oscillator and mixer performance. Tube sockets, controls, and jacks need cleaning with contact cleaner, and the tuning dial and meter mechanism should be inspected for smooth operation. After servicing, the IF and RF stages need realignment with proper test equipment to restore optimal sensitivity and selectivity. Before any of that, power the unit up through a variac or current limiter during initial testing, because a cold start on a sixty-year-old power supply can end the project early.

The FM-50 is respected for its build quality and its historical significance as a bridge between mono FM and the stereo era. It's not the rarest Fisher tuner, and it's not the most sought-after.