The also as direct mixer described receiver consists out of a bandpass filter, mixer IC, VFO and AF filter. For the construction of this simple circuit only 22 parts and somef time at a weekend are needed. If you like it a bit more simple, then eliminate L1/C1 and connect C2 to the slider of P1.

The free transistor, integrated in the NE612, is used a series-tuned Colpitts- or Clapp oscillator. Depending on the added parts the receive range is from 10050 kHz to 10250 kHz. Due to component tolerances the number of turns and/or the capacity of the frequency relevant components L3 and C7 have to be varied eventually .

The mixer is followed by a selective audio amplifier. One on the other balanced DC voltage levels at the mixer outputs and amplifier inputs allow a component saving direct coupling. After suppressing the unwanted RF products by C9 and C10 the remaining AF is passed through to the non-inverting inputs of TL072 dual op amp. A series resonant circuit, built out of Dr1 and C1, aids some AF selectivity. The AF stage has a gain of 46 dB at its 660 Hz resonant frequency. Audio power can be achieved by the attenuator P1 at the antenna terminal. TL072 outputs aren't of low impedance. So, when connecting 60 ohm headphones one should arrange a 470 ohm resistor in series.

The receiver operates in a voltage range from Ub=8 ... 15 V. The AF stage is supplied directly by Ub and the mixer gets a +6 V constant voltage from IC2. The receivers current consumption is approx. 6 mA with no input signal. You can save 1 ... 2 mA when using a 6 V regulator type with lower quiescent current.

For the receiver alignment the existing main-station rig is sufficient. Check the VFO frequency first. Receiver tuning should be possible between 10050 kHz (C4 max.) and 10250 kHz (C4 min.) by means of the variable capacitor. For this, listen to the own VFO signal at the main rig. Finaly adjust C1 and C3 to 10100 kHz, maximum audio power of an operating amateur radio station.