Lafayette HA-350 Приемник
Производитель:
Модель:
HA-350
Дата:
1964
Категория:
Группа:
Описание:
AMATEUR COMMUNICATIONS RECEIVER

Информация

The Lafayette Model HA-350 is a dual-conversion superheterodyne communications Receiver covering the 80, 40, 20, 15 and 10 meter amateur bands with provision for tuning WWV on 15 Me. The Receiver provides for the reception of CW (code), AM voice and SSB signals. During SSB operation, either the upper or lower sideband may be readily selected by means of a front panel control, a feature that greatly simplifies tuning of these signals. The Receiver employs dual-conversion on all bands (except 80 meters) and thus offers high image rejection. A crystal-controlled first conversion Oscillator and a VFO-type second conversion Oscillator ensure extreme accuracy and stability. Tuned RF and 1st mixer stages (Preselector) assure maximum sensitivity and a high signal-to-noise ratio. A 455 Kc mechanical filter plus two IF stages provide a high degree of selectivity — bandwidth is 2Kc at 6 db down, 6 Kc at 60 db down. A product detector operating with a crystal-controlled BFO is employed for improved CW and Single Sideband operation, while a separate diode detector is used for AM reception. Tuning in this Receiver is accomplished by a precision vernier mechanism that operates smoothly without backlash or other undesirable effects. The tuning method employed permits high accuracy. A single tuning dial, calibrated in kilocycles, is used to tune over all amateur bands. For even greater accuracy, the Receiver incorporates a 100 Kc Crystal Calibrator circuit (crystal available as an optional extra), plus a Calibration Reset control which permits accurate calibration of the tuning dial at every 100 Kc point. Other features include an “S” meter calibrated in “S” units from 1 to 9 and in decibels above S9, RF Gain control, Automatic Noise Limiter on AM, Receive-Send switch and a full-time AVC circuit which is automatically set to provide a characteristic most suitable for the mode of operation — “standard” on 9M, “fast attack — slow decay” on CW and SSB. The Antenna input connector is of the coaxial type and is designed for use with unbalanced lines of 50 to 75 ohms impedance. The Receiver has output terminals for connection of 8 ohm speakers, plus provision for 500 ohm connections. A front panel jack provides for headphone listening, the insertion of a headphone plug automatically silencing any speaker connected to the 8 ohm output terminal. The Receiver is designed to operate from an input power source of 105-120 volts, 50/60 cycles AC, the power transformer being fused in the primary for 2 amps. Full-wave rectification is employed, using silicon rectifiers. A voltage regulated B+ supply is provided for the BFO, 1st Conversion Oscillator and 2nd Conversion Oscillator to assure maximum stability.

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Обслуживание и Руководство пользователя
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16
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1.74 Mbytes (1824960 Bytes)
Язык:
english
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Hасто́льная кни́га ID:
99-2524WX
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Отсканированы документу, все читается.
Дата загрузки:
2015 09 06
MD5:
539a223e74ab3f90377812ac171623e3
Загрузки:
771