Manufactured by Lowe, Lowe Electronics Ltd, Bentley Bridge, Chesterfield Road, Matlock Derbyshire DE4 5LE.

Around 1991, British manufacturer Lowe, whose sets took an unconventional approach to no-frills shortwave reception, came up with the compact HF-150. Around 1987, Lowe had made its first step as a developer of shortwave receivers with its uncompromising HF-125. A few years later, the more compact HF-150 was released, with certain features only available in the form of an external add-on.

The HF-150 is a battery powered high performance travel receiver, with the external components it becomes a complete tabletop receiver.

• Principle: Double conversion superhet, IF 45 MHz / 455 kHz
• Operation modes: A1, USB/LSB, AM (A3), synchronous demodulator
• frequency range: 30 kHz - 30 MHz
• Frequency display: digital display, 1 kHz
• Frequency memory: 60
• Signal strength indicator: none, external S-meter LS-150
• Signal processing: Synchronous demodulator
• Features:
• Sensitivity: AM (A3) 1 μV / Selectivity: 2.6/4.1 and 6.5/10.2 (nominal 7) kHz (-6/-60 dB)

• Mains operation: (12 V resp. 10 - 15V), 300 mA) with external 220 V power supply.
• Batteries: 12 V resp. 8 x 1.5 V batteries (UM-3)

• 185 x 80 x 175 mm, weight 1.3 kg (with batteries 1.5 kg)

• Preselector PR-150
• Loudspeaker / S-meter LS-150, for correct display of the signal strength, a modification is necessary.
• Rack
• Frequency input keyboard KPAD-1
• Accessory Kit AK-150 with a telescopic antenna, a harness with integrated antenna and eight NiCd accumulators.
• Computer - Interface IF-150

The receiver can be operated either standalone as a travel receiver (with eight batteries or accumulators, it is even mains-independent); with an external preselector and a S-meter / loudspeaker combination in a rack, it becomes a resonable tabletop receiver.

The receiver itself is built into a milled aluminum housing. The front panel has a very spartan aspect with it's only five controls. The LCD display, unfortunately it is not backlit, is located in a black raised area, the combined main switch / volume control on the left, three pushbuttons below the display and the tuning knob on the right.

As mentioned above, the set is turned on with the volume control knob, a hiss should be audible in the loudspeaker, the receiver jumps to the last set frequency after is switched on. If a headphone is plugged into the headphone jack, the built-in speaker is switched off.

The frequency can now be set by use of the large tuning knob, the right FAST button sets the tuning steps to 100 kHz, in order to approach the desired shortwave band more quickly. If FAST is pressed again, the radio returns to fine tuning, in AM operation mode with 60 Hz and in SSB operation with 8 Hz tuning steps.

Pressing the middle MODE key indicates the operation mode, which is active. The RIGHT or LEFT key can be used to switch between the different operation modes. Letter codes indicate the Operation mode:

• A: AM wide, 7 kHz filter
• An: AM narrow, 2.5 kHZ filter
• ASd: AM synchronous demodulator, dual side band, 7 kHz.
• ASF: AM synchronous demodulator, 7 kHz, high fidelity
• ASL: AM synchronous demodulator, lower side band 2.5 kHz
• ASu: AM synchronous demodulator, upper sideband 2.5 kHz
• LSb: SSB LSB (Lower side band)
• Usb: SSB USB (Upper side band)

When the MEM key is pressed, the receiver is set to memory mode, indicated by a small mark on the display under MEM. Now, when the tuning knob is turned, the various memories are recalled. The receiver can store up to 60 frequencies by pressing MEM and then STO(re).

There are more elements on the rear face of the set, than on the front. Four UM-3 batteries or rechargeable accumulators can be inserted into the two battery compartments. The inserted batteries are charged when the set is supplied with 12 V DC and is turned off. If there are normal batteries in the battery compartments, the set must not be operated from 12 V or the mains adapter - the batteries cannot be charged and risk to explode. So in case of mains operation, remove batteries or release the battery holders from the detent position by lateral pressure and pull them out a little bit.

On the rear panel are the antenna connectors, a 50 Ohm coax socket and screw terminals for a (long) wire antenna. The sensitivity can be switched: in position WHIP (rod antenna), a preamplifier is activated and a telescopic antenna can be connected to the SO 239 connector. Since the receiver tends to overload without preselection, the attenuator ATTEN must be activated at high signal levels.

Furthermore, the jack for the external frequency keyboard, a line out and a speaker jack and the 12 V DC connector (center - positive, 5.1/2.1 mm low voltage connector) can be found here.

Since the RF front end of the HF-150 is designed without preselection, the signal is passing only a low-pass 30 MHz filter, the large-signal response on long antennas is not optimal: a preselector must be used to improve the large-signal performance. To improve the large signal performance, Lowe offered the active preselector PR-150 with similar dimensions.

The external preselector can be bypassed in the WIDEBAND position, if the signal situation is unproblematic. The bandpass can be selected with UP/DOWN keys and then tuned to signal maximum with the preselector tuning knob. A switchable preamplifier and attenuator is also integrated in the PR-150 and two different antennas (A: unbalanced; B balanced dipole antenna) can be selected.

The SP-150 is an external speaker, equipped with an adjustable notch filter and a low-pass filter, the treble tone response can be adjusted to improve intelligibility. In addition, a red backlit S-meter is integrated into the SP-150; to activate it, a trace must be interrupted on the HF-150's PCB, according to the description in the manual.

The receiver is designed as a double conversion superhet with a high first intermediate frequency of 45 MHz, at the front end a low pass filter cuts all frequencies above 30 MHz. However the manually operated preselector PR-150 offers manual preselection, which massively improves the large signal characteristics.

The set is completely solid state.

Technical documents are available on the WWW, unfortunately I don't own the original documents to provide scans here.

• Lowe HF-150 on the website of www.radiomuseum.org