Ramsey Electronics Initial Testing of Your HR20, Required for Initial Testing and Alignment

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INITIAL TESTING OF YOUR HR20:

You’re now ready to power up and test your HR20, but before you begin take some time to sweep off your bench of any loose component leads or solder splashes. A clean work area not only makes testing less frustrating but also less prone to problems.

REQUIRED FOR INITIAL TESTING AND ALIGNMENT:

A known frequency standard in the 10MHz range such as:

Crystal oscillator or,

RF signal generator or,

Grid Dip oscillator or,

QRP transmitter such as a Ramsey QRP-20

A Ramsey frequency counter, CT-90 or,

Any accurately calibrated receiver covering 20 meters

At the least,personal familiarity with the 20 Meter Ham band

And the following:

Coil alignment tool ( can be homemade per directions) and

9-volt battery, antenna earphones or a small speaker.

Connect the following:

‰Fresh, 9-volt battery.

‰Earphone or speaker.

Antenna or at least a random length of wire.

‰Adjust the three controls to the middle of their ranges.

‰Press the power switch “on”. You should hear background noise immediately, at least a gentle hiss.

‰See if the volume control works, vary it and notice how the volume changes.

‰See if the RF gain control has some effect on what you hear.

‰If everything seems ok so far, feel the tops of the two IC's with your finger. Neither should feel hot or warm

‰Slowly rotate the tuning control. At this point you may or may not hear anything, since neither coil has been adjusted. If you do hear a few whistles as you tune, the SA602 oscillator is working just fine.

‰These simple initial checks verify that your receiver is operating well enough to proceed to the next section, alignment.

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Contents ALL Mode Receiver KIT Partial List of Available Kits Ramsey Transmitter Kits HR20 Amateur Receiver KIT Introduction Ramsey HR-SERIES Amateur ReceiversAbout Direct Conversion Receivers Circuit Description Capacitors Parts Supplied with the HR20 KITLEARN-AS-YOU-BUILD Receiver Assembly Strategy HR20 HR20 Parts Layout Diagram Receiver Assembly HR20 HR20 Initial Testing of Your HR20 Required for Initial Testing and AlignmentAlignment Alignment Hint for ALL Direct Conversion ReceiversCW Operation Using Your ReceiverTuning SSB Signals On the AIR TRANS-RECEIVINGSpeaker Operation More Audio Power Another WAY Adding AN LED Power on IndicatorTroubleshooting Tips Alternate Power Sources General Notes for Experienced QRP BuildersBandspread and Tuning Range Direct Frequency Readout Frequency StabilityOther Methods of Dial Calibration LM386 Audio Output HR20 Construction Notes Ramsey Kit Warranty Factory Repair of Assembled Kits Required Tools Total Solder Points Estimated Assembly TimeHR20 Amateur Receiver KIT Additional Suggested Items