TRIO KR-77
¥ 58,900 (around 1969)
Commentary
FM/AM receiver equivalent to the low power version of KR-100.
By using carefully selected silicon transistors, high sound quality is achieved.
The equalizer amplifier section uses a direct connection between the amplifier stages, eliminating the influence of capacitors and resistors and enabling more accurate reproduction from lower frequencies.
Equipped with an automatic return type power transistor protection circuit.
Equipped with an output selector.
The FM front-end uses a four link varicon and FET to improve the receiving capability.
High-gain ICs are used in the IF stage to obtain high sensitivity, and a limiter works from the time of Tsutomu Oire to enable reception with less distortion.
In addition, the noise limiter circuit, which cuts out external noise, is composed of four stages to cut off external noise.
Equipped with a pure electronic FM mono-stereo automatic switching circuit that automatically switches to stereo when stereo broadcast transmission.
When receiving stereo signals, the stereo indicator lamp on the dial is turned on.
A muting circuit is installed to reduce inter-station noise generated during FM channel selection.
Model Rating
Type | FM/AM Receiver |
FM Tuner Section | |
Receiving frequency | 76 MHz to 90 MHz |
Sensitivity (IHF standard) | 1.5 μ V |
Distortion factor | 0.5% or less (400 Hz, 100% modulation) |
Signal-to-noise ratio | 60 dB or More (100 μ V input, 100% modulation) |
Frequency characteristic | 20 Hz ~ 20 kHz + 0 -2dB |
Frequency drift | 0.02% |
Antenna input impedance | 300 Ω, 75 Ω |
Capture ratio | 2.5 dB or less |
Image rejection | 80 dB or more |
Harmonic spurious response | 90 dB or more |
IF Rejection | 80 dB or more |
Selectivity | 45 dB or more |
Stereo separation | 35 dB or more |
<AM Tuner Section> | |
Receiving frequency | 520 kHz to 1610 kHz |
Sensitivity (IHF standard) | 15 μ V |
Image rejection | 90 dB or more |
Selectivity | 25 dB or more |
IF Rejection | 70 dB or more |
Amplifier Unit | |
Music Power (IHF) | 75W ± 1 dB (4 Ω) 56W ± 1 db (8 Ω) |
Effective power | Single-Channel Operation : 33W/33W ± 1 dB (4 Ω) 24W/24W ± 1 db (8 Ω) Both channel operation : 18W + 18W ± 1 db (8 Ω) |
Total harmonic distortion factor | 0.5% or Less (Rated Output) |
Cross modulation distortion factor | 0.5% or Less (Rated Output) 0.2% or Less (Rated Output -3dB) |
Frequency characteristic | Main in : 15 Hz to 50 kHz ± 1.5 dB Aux : 20 Hz to 30 kHz ± 1.5 dB |
Output Bandwidth Characteristics (IHF) | 20 Hz to 30 kHz |
Input sensitivity | Phono1, 2 : 2.0 mV Tape HD:2.3mV Aux, Tape play (Pin) : 200 mV Main in:100mV |
Recorded output | Tape rec(Pin):200mV Tape rec(Din):40mV Dubbing:200mV |
Maximum Input Voltage | Phono : 180 mV (P. P, 1 kHz) |
Tone control | Bass : ± 10 dB (100 Hz) Treble : ± 10 dB (10 kHz) |
Loudness control | + 10 dB (100 Hz), + 5 dB (10 kHz) |
Low filter | 200 Hz, 6dB/oct. |
High filter | 3 kHz, 6dB/oct. |
Signal-to-noise ratio | Phono:60dB Tape HD:60dB Aux, Tape play : 70 dB |
Residual noise | 0.8 mv (8 Ω) |
Damping factor | 24 |
<General> | |
Accessory circuit | FM mono to stereo automatic switching device Stereo display lamp Muting switch SCA Filters AM bar antenna |
Semiconductor used | Transistor : 35 FET : 2 IC : 2 Diode : 34 pcs |
Pwer | 100 VAC / 117 V, 50Hz/60Hz |
Power consumption | 20W (no signal) 113W at maximum output |
External dimensions | Width 420x Height 140x Depth 310 mm |
Weight | 10.5kg |