Inhaltsverzeichnis
JRC NRD-1E
Manufactured by the Japan Radio Company.
The NRD-1E is an all wave receiver designed for maritime and commercial use, with a design quite similar to the Collins 51J-4.
Technical data
- Frequency range: 90 kHz - 30 MHz
- Frequency display: linear analogue display, accuracy up to 1 kHz
- Frequency memory: none
- Features: Motor tuning
Power supply
- Mains operation: 110 - 120 V
Dimensions
- 489 x 240 x 400 mm, weight 23 kg
Accessories
- SP-101: external loudspeaker
Operation
The NRD-1E is an all wave receiver used in naval and commercial radio, quite similar in design to the Collins 51J-4. Possibly the NRD-143 mentioned on a Finnish website, which is extremely close in design to the 51J-4, could be the „missing link“.
The tube-equipped receiver was developed around 1965 and covers a range of 90 kHz - 30 MHz, up to 7 MHz it works as a Triple conversion supherhet, above that as a Double conversion.
There is a rack and a desktop version of the set, the latter has a weight of 23 kg and dimensions of 48.9 x 24 x 40 cm. The set is designed for the Japanese market and was intended to be operated from the 110-120 V mains that is common in Japan. For operation from the European mains voltage of 230 V, a 230/115 V transformer as well as an external loudspeaker (original JRC SP-101) are required.
The front panel is already very similar in design to those of later NRD receivers. The frequency dial is located in the middle: the frequency band switch at the bottom left selects the 1 MHz range, a luminous mark indicates the range on the upper dial. The tuning knob moves another luminous marker, which indicates the 100 kHz position on the lower linear dial with 100 kHz dial markings; the kHz digits are indicated on the rotating dial above the tuning knob. With a 100 kHz crystal calibrator („Calibrate“), the 0 kHz position can be located and the pointer line of the analogue dial shifted accordingly.
The receiver is equipped with motor tuning, a press on the AUTO button is sufficient and the tuning knob moves as if by magic, if the motor noise were not unmistakable.
The RF gain control is located to the left of the main tuning knob, the switch in the upper right corner can be used to select three tuning speeds or to manually adjust the RF gain, to the right of the main tuning is the volume control labelled „AF Gain“, right next to it the bandwidth switch and the jacks for headphones and speakers.
To the left and right of the kHz dial are the switch and pitch control for the BFO for CW and single sideband reception.
The main switches are found on the right and are labelled POWER A and B, their function is not quite clear to me, for operation both have to be switched on, probably one switch activates the tube heaters (for preheating) and the second one the plate voltage for operation, similar to the HRO where B+ also switches the plate voltage.
The antenna connector of the preselector is located at the top right of the rear panel; it is connected with a cable to the antenna input of the receiver at the bottom of the chassis. Next to an IF output there is a multi-pin connector, the audio signal can be picked up at the two horizontal contacts in the lower right corner.
The inner workings of the NRD-1E are impressive and reminiscent of the 51J-4 with the round PTO (an orange „can“ with nice Japanese lettering) placed in the centre, but the mechanics are far less elaborate.
The mechanical filters are located in the front right corner of the chassis, the inner workings of the set are easily accessible thanks to the hinged lid, and the internal construction is solved in an exemplary manner, as with later NRD receivers.
After connecting an appropriate power source, operation is no problem at all for anyone who has ever sat in front of a 51J-4 (or who owns an NRD-505/515): Select the MHz band with the band selector, set the frequency (if you don't like to crank for a long time, you can press the AUTO button and enjoy the motor tuning), set the RF gain to the right stop, AGC to L, bandwidth to 6 or, in case of adjacent channel interference, to 3 kHz, and you're ready to start station hunting in the shortwave broadcast bands; for CW reception, select the narrow filter and activate the BFO.
After an uncertain amount of time and without any adjustment, my NRD-1E connected to a random wire antenna picked up several stations in the 25m band with nice levels and pleasant intelligibility from the loudspeaker. Of course, the NRD-1E is a collector's set, the newer solid state NRD's will probably quickly outclass it in terms of frequency stability and dial accuracy, but as a JRC enthousiast, it is a great feeling to sit in front of a tube-equipped receiver that not only can be operated like an NRD-515 but is also a genuine NRD receiver.
Technical principle
Triple / double conversion superhet.
Components
The set is hollow state.
Technical documentation
none found, I would be grateful for service documents
