Manufactured by Japan Radio Co., Tokyo.
The NRD-1107D is an easy-to-use professionally built marine radio receiver, designed entirely for the needs of radio communication with stations on fixed frequencies.
- frequency range: Maritime communications bands 1.6 - 25.9 MHz
- Frequency display: digital display, 100 Hz
- Frequency memory: none
- Sensitivity: AM (A3) / selectivity: kHz (-6/-60 dB)
- Mains operation: (110,) 230 V
- 480 x 130 x 450 mm, weight 10 kg
The NRD-1107D is a professionally built 19-inch rack-mount receiver for maritime communications. According to the nameplate, it was manufactured in 1977. In its original state it was probably operated from 110V AC, my set is set to 230 V AC.
The front panel has - as usual with JRC sets - a very straightforward design.
The main switch is combined with the volume control (AF GAIN), to the left of it is the RF gain control, when the AGC is switched off, this is used to manually control the RF gain. To the right of the volume control is the BFO button for single sideband and CW reception and an antenna trimmer.
Push-buttons on the top left of the front panel select the Operation mode, A3J for single sideband reception, A1 for CW reception of Morse code transmissions and A3A for normal AM reception.
The rotary switch „BAND“ to the right of it selects the marine communications bands starting from 1.6 / 2 / 3 / 4 / 6 / 8 / 12 / 16 / 22 / 25 MHz in 1 MHz wide segments, the subdivision in the lowest frequency ranges 1.6 - 2 / 2-3 / 3-4 MHz is also selected with push buttons. One position of the band switch activates the fixed frequency reception of the international distress frequency of 2182 kHz, the NRD set will probably often have been used as a secondary receiver for continuous observation of this frequency.
Due to the available frequency ranges, it is immediately obvious that the NRD-1107D was built primarily for maritime use, most broadcast bands and the amateur radio ranges cannot be tuned.
The position of the band switch affects the red LED display of the MHz digits of the reception frequency, the 100 kHz, 10 KHz, 1 kHz and 100 Hz digits are set with decadic rotary knobs.
This receiver concept is similar to the Rohde & Schwarz EK 047, among others. In the professional field with reception of stations on fixed frequencies, the search reception by means of a VFO rotary knob is rarely required for sets that are not used for frequency monitoring purposes.
The NRD-1107D does not have a built-in loudspeaker. The AF signal is fed out via a multi-pin connector on the rear panel, and there is only an SO-239 antenna connector and an earth connector on the back of the unit.
As explained above, the operation is almost self-explanatory. Switch on the set with the AF gain control, set the AGC control to ON, set the mode switch to A3A to receive Austrian Radio Intl., set the band switch to 6, use the knobs underneath the digits to set 6 1 5 5.0 and you will hear the signal coming from Vienna. If you want to try RAF Volmet on 4722 kHz, set the Operation mode to A3J, band to 4, the frequency selector knobs to 4 7 2 2 and here you go.
For the shortwave enthusiast, the set has some limitations to be suitable as a hobby receiver: The main problem is that only the marine radio bands are covered, but the tropical band enthousiast gets his money's worth with the available bands. The lack of a VFO for search reception and the missing memory options are further weak points, feaures for signal post-processing are missing, but then the list would soon come to an end - the reading accuracy and frequency stability and the useful sensitivity as well as the large signal behaviour are, as with all sets from JRC, more than satisfactory.
Double conversion superhet.
The set is solid state.