ANTENTOP- 01- 2009, # 011

Tube AM Radio Station for the 160- meters

Glow-discharge stabilitron VT1 and VT2 may have voltage 80- 150-V. Any low power double triode may be used at receiver (VT5). Any low power RF- pentode may be used at VT6.

Coil L4 may be moved along L5. It is need to get optimal regime for the regenerative receiver. Figure 2 shows the design of the receiver's coil. Relay K1- any suitable relay. R18 limited current through the relay.

Figure 2 Design Coil of the Receiver

Tuning of the Radio Station

The tuning is simple and takes one evening if the radio station is made from right parts that are installed in correct way.

At first do tuning of the receiver. Receiver should receive something with antenna at least 3 meters long. Tune L3C12S3 for the best receiving. With help C19 set the receiver to the middle of the 160-meters band. Be sure, that C18 covers all 160-meters band. R6 should provide a smooth regeneration control. If not, change the distance along L4 and L5. If it is no regeneration, switch visa versa terminal of L4 or decrease distance between L4 and L5. Set the receiver in the middle of the 160s and tune L6C20 and then L7C23 on to maximal sensitivity.

The second, do set up of the transmitter. Begin from the VFO. Using MW receiver set the VFO to 900- kHz (300-meters). Load the transmitter to a 50-Ohm/10-Wtts resistor or bulb having resistance in range 50- 300- Ohms. Adjust doubler L2C5 on to maximum output power of the PA. Audio amplifier/modulator works straight away at right parts. Audio transformer T1 was used from an old tube receiver.

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