FR-1 • 14
SPEAKER SELECTION
A fifty-cent' speaker, lying naked on your workbench will not give you a fair test
of your FR1 audio quality or volume. Speaker quality and well-designed
enclosures have their clear purposes! A reasonable speaker in a box delivers a
pleasant listening volume as well as significantly improved fidelity.
ADDING A POWER-ON INDICATOR
Adding a simple LED power-on indicator to your Ramsey kit receiver is easy.
All you need is the LED itself and a small 1K ohm 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 logical and ideal. The simplest way
to make a neat installation is to drill a hole just slightly 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 of the LED, but the anode side MUST go to + DC,
with the cathode connected to the nearest common ground point.
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: drawing about 15 ma., how long will your battery last if you
leave you receiver on for a few days, just like we leave our computers, ham
radios or accessories on all the time? (2) We thought you'd have more fun
planning and installing you own lamp that glows in the dark! (3) We couldn’t
decide which color you would like best.
TROUBLESHOOTING TIPS:
PROBLEM: ALL signals are hard to tune, unstable, 'jumps away'.
SOLUTION: The oscillator is tuned on the wrong side (10.7 Mhz BELOW
rather than above) of the desired receive frequency. Retune coil L1. Also this
condition could be caused by a weak battery! Use a fresh alkaline cell. Any
strong signal forces the audio circuit to rob voltage from the oscillator, which
causes the instability.
PROBLEM: Occasionally good but erratic operation.
SOLUTION: Check very carefully for poor solder connections.
PROBLEM: Loud AC hum or buzz.
SOLUTION: . If you are using a 9-volt AC power adapter, the adapter design
may not be of sufficient quality for this application. Try bypass capacitors, a
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