Pioneer TX-80
¥ 42,800 (around 1971)
Commentary
A tuner designed with an emphasis on high fidelity reception.
The using a high-frequency two stage amplifier circuit with FET (field effect transistor) and four variable capacitor at the front end, we can receive signals with less noise and distortion even in low-power regions.
A five stage amplifier circuit using three ceramic filters is used for the IF section.
The MPX part adopts switching system for the circuit, and is composed of parts combining an IC and a perfectly sealed transformer which is resistant to changes in temperature and humidity.
In addition, noise that is likely to occur during stereo reception in low-power areas is cut off by a noise filter that works in conjunction with the selector switch.
The AM section employs an IF circuit using a tunable high-frequency amplifier circuit and a ceramic filter.
A high-grade AGC circuit is also used.
It is equipped with a ferrite bar antenna with a new mechanism capable of changing the direction over a wide range.
Equipped with two meters for signal strength and center tuning.
Equipped with an FM muting switch, it can cleanly cut unpleasant inter-station noise.
AM and FM are equipped with independent output level control.
Equipped with an FM multipath terminal, it can connect to a Pioneer stereo display (SD-100, ¥ 108,000) or an oscilloscope, observe the waveform on the CRT, and determine the position, direction, and height of the antenna without multipath interference.
Equipped with a Tape Rec connector.
Model Rating
Type | AM/FM stereo tuner |
FM Tuner Section | |
Practical sensitivity | 1.8 μ V (IHF) |
Capture ratio | 2.0dB(IHF) |
Execution selectivity | 70 dB or more (IHF) |
Image interference ratio | 90 dB or More (82 MHz) |
IF interference ratio | 100 dB or More (78 MHz) |
Spurious response | 100 dB or More (82 MHz) |
AM suppression ratio | 50 dB or more |
Signal-to-noise ratio | 70 dB or more |
Harmonic distortion factor | Mono : 0.4% or less (100% modulation) Stereo : 0.5% or less (100% modulation) |
Tuning indicator | 2-meter method (signal, tuning) |
Muting | ON-OFF enabled |
Stereo separation | 40 dB or More (1 kHz) |
Residual carrier level | 50 dB or more |
Antenna | 300 Ω Balanced Type 75 Ω Unbalanced Type |
Accessory circuit | Stereo to mono automatic switching Multi-path terminal MPX Noise Filter |
<AM Tuner Section> | |
Practical sensitivity | 10 μ V (IHF) |
Image interference ratio | 80 dB or More (1000 kHz) |
IF interference ratio | 70 dB or more |
Signal-to-noise ratio | 50 dB or more (at 30% modulation, 74 dB input) |
Antenna | Ferrite bar antenna installation |
Tuning indicator | Meter indication |
<Low Frequency Portion> | |
Output voltage | FM : Maximum 2.4 v ~ Minimum 80 mv (100% modulation) AM : Maximum 2.4 v ~ Minimum 80 mv (100% modulation) |
Recorded output | FM : 750 mV (terminal open, 1 kHz, 100% modulation) AM : 750 mv (terminal open, 1 khz, 100% modulation) |
Accessory circuit | Output Level Control (AM/FM) |
<General> | |
Rated power consumption | 25W |
External dimensions | Width 430x Height 145x Depth 345 mm |
Weight | 7.5kg |