Quad FM3 Tuner

Originally launched in 1971, production of the Quad FM3 Tuner continued until 1982 at which time approximately 50,000 units had been sold. It should come as no surprise therefore that our example has a few signs of wear – please see photographs. However, it is in full working order and will be packaged appropriately, and it also comes with our usual 3 month warranty.
Quad Say….
The purpose of VHF/FM broadcasting is to provide reception, within the service area of the transmitter (normally 50 to 100 miles), free of interference and capable of reproduction at very high quality. The Quad FM3 tuner will completely fulfil this purpose with any transmission which arrives at the aerial in a condition capable of full quality recovery.
Outside the service area of the transmitter it is the nature of VHF/FM for signal strength to fall rapidly and there will be a tendency to fading but the high sensitivity of the FM3 tuner enables it to receive such signals with two reservations: 1, no tuner can improve the signal/noise ratio of the signal as it arrives at the aerial and 2, the considerable bandwidth essential for low distortion reproduction means that a weak station can be resolved only if it is sufficiently separated (i.e. by at least 400 kHz) from any other more powerful signal.
In most areas the local VHF/FM services are normally receivable at reasonable signal levels. Between these stations on the tuning scale, among the background noise, there will usually be distant stations spilling over from other areas. Because the FM3 inter-station noise suppression circuit is adjustable the owner can decide where to set the suppression level between complete silence between one strong station and the next, on the one hand, and no suppression at all so as to rake in every scrap of signal (and noise) on the other. Also as the suppression system provides muting until the station is correctly tuned, not only is background “hash” supressed but the unpleasant noises associated with tuning through the sidebands of the station are also avoided, and with strong stations it is possible to proceed from one perfectly tuned programme through silence to the next perfectly tuned programme.
Operating the FM3 is simple, the only control on the front of the FM3 tuner being the tuning knob (which is also used for setting the station markers) and no others are required. The noise suppression adjustment is a pre-set control at the rear of the tuner and all other controls, volume stereo-mono switching, mono hold, on/off, are provided by the associated Quad 33 control unit.
The positions on the scale of any five stations may be indicated by pre-set markers. These are positioned by pressing the tuning knob to engage its pointer with each marker in turn, tuning to the stations to be marked and releasing the knob. The markers then stay in position for future reference.
The tuning indicator is the original Quad twin lamp system, first developed by Quad in 1955, which provides for simple, positive and highly accurate tuning.
Specifications:
Frequency Range: 88 – 108 MHz
Aerial Input: 75 Ω coaxial; 300 Ω balanced
Full Limiting: < 2µV
Image Rejection: 56 dB
IF Rejection: 80 dB
400 kHz Selectivity: 46 dB
Capture Ratio: 3 dB
IF Bandwidth: < – 3 dB at ± 120 kHz; > – 60 dB at ± 400 kHz
Output at 38 kHz and above: – 50 dB
Frequency Response: ± 1 dB 20 Hz – 15 kHz
Channel Separation: 40 dB at 1 kHz
Distortion: at 1 kHz and ± 40 kHz deviation: 0.2%
Output: 100 mV per channel for 30 % modulation
Source Impedance: 5 kΩ
Recommended Load Impedance: > 50 kΩ
Recommended Load Capacity: < 1000 pF
De-Emphasis: 50 µ Sec or 75 µ Sec as required
Power Input: 100 – 125 / 200 – 250 V; 50 – 60 Hz; 6 VA
Dimensions: 260 (W) x 165 (D) x 92 (H) mm
Weight: 2.7 kg