Ramsey Electronics HR40 manual Using Your Receiver, Tuning SSB Signals, CW Operation

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USING YOUR RECEIVER:

In your first tests, you might feel that tuning in CW and SSB stations by turning the control shaft seems tricky. Don't despair! The addition of a simple knob to the final version of your kit will result in more comfortable tuning right away. Also, the larger the knob, the easier the tuning is. Even smoother control can be accomplished by a vernier dial, which will also provide calibration marks. Finally, if you intend to use this receiver only for monitoring or working a very specific frequency range, you can add a resistor in series with the tuning control to achieve the bandspread you want for your own application. For details, please see the upcoming section, Notes to Experienced QRP Builders.

We want you to enjoy this economical receiver, whether you use it for portable listening or as a base for easy experimentation. Isn’t it amazing the performance that can be achieved with just two IC chips?

•TUNING SSB SIGNALS

As you know, the protocol for the 160 - 80 - 40 Meter Bands is lower sideband (LSB), with Upper Sideband (USB) used for 40 - 18 - 15 - 12 - 10 Meter SSB. To check or ‘scan’ a given band for SSB signals, tune your HR40 up from the low end for USB signals and down from the high end for LSB.

•CW OPERATION

A direct-conversion receiver lets you hear equal ‘sidebands’ on either side of the zero-beat ‘null’ of the exact frequency of the signal to which you are listening. Therefore, when adjusting the frequency of your companion Ramsey QRP transmitter, be certain that you have in fact tuned to the other station’s lower sideband. The two stations will actually be several KHz apart. Because this receiver’s oscillator is not shared with a transmitter, as in transceivers, there is no need for separate RIT (receiver incremental tuning).

•ON THE AIR TRANS-RECEIVING

Let’s assume that you plan to use this receiver together with a Ramsey QRP transmitter, which provides an RF protected receiver antenna jack. While the receiver will be protected from RF damage from the transmitter, do not expect to monitor your own signal on this receiver while transmitting unless you are a QRP design expert and do not care about future factory service from Ramsey. Even with the circuit protection, the RF signal is just too much for the SA602.

The transmitter signal overpowers the SA602, disrupting the internal oscillator. However, the receiver can handle the output of a crystal oscillator or VFO for frequency spotting purposes.

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Contents ALL Mode Receiver KIT Ramsey Transmitter Kits HR40 Amateur Receiver KIT Introduction Ramsey HR-SERIES Amateur ReceiversAbout Direct Conversion Receivers Circuit Description Parts Supplied with the HR40 KIT CapacitorsLEARN-AS-YOU-BUILD Assembly Strategy HR40 Parts Layout Receiver Assembly Page Page Initial Testing of Your HR40 Required for Initial Testing and AlignmentAlignment Alignment Hint for ALL Direct Conversion ReceiversUsing Your Receiver Tuning SSB SignalsCW Operation On the AIR TRANS-RECEIVINGAdding AN LED Power on Indicator More Audio Power Another WAYSpeaker Operation Page Troubleshooting Tips Bandspread and Tuning Range Alternate Power SourcesGeneral Notes for Experienced QRP Builders Frequency Stability Direct Frequency Readout Other Methods of Dial CalibrationLM386 Audio Output PIN Count Megoh Construction Notes HR40 Ramsey Kit Warranty Factory Repair of Assembled Kits Total Solder Points Estimated Assembly Time HR40 Amateur Receiver KITRequired Tools Additional Suggested Items
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