Ramsey Electronics HR20 manual More Audio Power Another WAY, Adding AN LED Power on Indicator

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MORE AUDIO POWER - ANOTHER WAY

If you want to use your HR20 for casual band monitoring while you are busy across the room, in the shop, to share with a class or club or group and want LOTS more volume, try building up our very inexpensive Ramsey BN-9, 2 watt general purpose amplifier kit. Supply DC voltage to such an amplifier separately, using D-cells, a lantern or auto battery , or a well filtered power supply.

ADDING AN LED POWER ON INDICATOR

For many people, a pilot lamp to indicate “power on” is more than a nice touch. They expect it and depend on it , reminding us that “real radios glow in the dark!”

Adding a simple LED power-on indicator to your Ramsey HR20 is easy. All you need is the LED itself and a small 1K or 2.2K resistor. Study the PC traces between the positive battery supply wire and the on-off switch. The unused connectors on top of your switch are an ideal point to get the + DC voltage needed for the anode (longer lead) of the LED. Plan where and how you wish to install the LED in your enclosure. Locating the LED immediately above the on-off switch is ideal. The simplest way to make a neat installation is to drill a hole just sightly smaller than the diameter of the LED. Then, enlarge the hole a little bit at a time, just enough to let the LED be pressed in and held firmly. The resistor may be connected to either the anode or cathode side of the LED, but the anode must be connect to the + DC with the cathode connected to the nearest common ground.

If you are wondering why we did not include these pennies worth of parts with your kit , you can believe any of the following reasons: 1)We wanted to stretch your battery budget and the current draw on the LED is about 6ma. How long will your battery last if you leave your receiver on for a few days, just like we leave on our computers and Ham gear on all the time? (2) We thought you’d have more fun planning and installing your own lamp that glows in the dark!

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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 Frequency Stability Other Methods of Dial CalibrationDirect Frequency Readout 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