Hitachi SR-4019
AM/FM stereo receiver FTC rated for 8 ohms at 25 watts RMS per channel, 20 Hz
to 20 kHz , at no more than 0,05% Total Harmonic Distortion
Features include:
Left and right 5
step LED output power indicators, calinrated at 0,01; 0,1; 1; 10 and 30 watts
into 8 ohms, that also serve as an FM tuning indicator (left meter) and AM/FM
signal strength meter (right meter); an FM stereo beacon; an FM mute that is
applied automatically when the receiver is in the stereo mode (the mute is off
when the receiver is set for full time mono); and a subsonic filtter that is
applied automatically when the LED indicators are switched to the tuning
indicator mode (the subsonic filter is off when the meters are switched to
indicate output power)
There are inputs for
magnetic phono, and tape Outputs for two speaker systems, tape and [phones.
Controls are provided for tuning volume, balance, ganged bass, ganged treble,
speaker selection, and input selection/FM muting. There are switched for loudness
compensation, tape monitor, and meter mode/subsonic filter.
The FM antenna input
is 75/300 ohms. An internal antenna and external connection are provided for
AM. There is one unswitched AC outlet.
Tuner performance
FM Tuner. Full
limiting was attained with 2,8 µV. The monophonic high fidelity sensitivity (60
dB quieting) measured 8 µV. The stereo high fidelity sensitivity (55 dB
quieting) was 90 µV. Full mute release was attained with 6 µV. At standard test
level the stereo frequency response measured +0,2/-1,5 dB from 40 to 15,000 Hz,
down 2,2 dB at 30 Hz . Monophonic distortion measured 0,2% Total Harmonic
Distortion, stereo distortion was 0,5% Total Harmonic Distortion. The signal to
noise ratio measured 67 dB. Stereo separation was 36 dB. Selectivity was very
good. The 19 kHz FM pilot leakthrough is some what higher than average. Make
certain the MPX filter on a Dolby recorder is switched in when recording from
FM. On most recorders the MPX filter is automatically applied with the Dolby.
AM tuner. Background
noise was higher than average.
Amplifier
peformance. The power output per channel at the clipping level with both
chaannels driven 20 to 20,000 Hz into 8 ohms measured 27 watts RMS. The
frequency response at 27 watts/8 ohms measured +0 dB -3 dB from 20 to 20,000 Hz
at a distortion no higher than 0,06% Total Harmonic Distortion at any
frequency. The subsonic filter produced 2,5 dB attenuation at 20 Hz. The tone
control range measured =11/-12 dB at 50 Hz ; ±8 dB at 10,000 Hz. The magnetic
input hum and noise was -69 dB; stero separation was into the noise level.
Meters
The LED output power
indicators, because of the broad range between values, indicate approximate
power. They serve as a reference rather than as precise value. Their frequency
response is essentially "flat". When used as tuning meters the right
indicator functions as light-bar )or bar-graph) signal strength meter, while
the center LED in the left indicator serves to indicate proper tuning-it snaps
on when an FM station is tuned properly; essentially, the LED substitutes for a
center-channel tuning meter.
Dimensions (W x H x
D): 17-1/8" x 4-3/8" x
11-1/8"
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