Ramsey Electronics FM10A - Manual (Page 18)

Ham radio books and magazines are filled with antenna principles and ideas
which can be adapted to your application. Also, you may wish to look at Radio
Shack book No. 62-1083 on antennas.
ANTENNA ALTERNATIVES
If your situation involves a single large building or multi-level home where
reception from the FM10A antenna tends to be uneven because of walls and
other VHF path obstacles, you might set up the FM10A's output in a "carrier-
current" configuration. If you know how to do correctly, then do so - safely. If
not, you can show your FM10A and this book to a licensed radio engineer and
negotiate with that person for a safe installation which will feed your signal
through interior wiring of your home or building. Do not attempt such an
installation unless you know exactly what to do and not to do. Also, because
such an installation is beyond the original purpose of this kit and the safety
standards intended for all Ramsey kits, and because we have not tested the
FM- 10A in such an installation, we cannot provide further details for such an
installation.
TROUBLESHOOTING GUIDE:
If your FM10A does not work at all, re-check the following:
ˆ
correct orientation of U1 (see PC board parts layout diagram)
ˆ correct polarity of all electrolytic capacitors,
ˆ Correct orientation of diodes D1,2,3,
ˆ correct orientation of Q1 transistor,
ˆ correct value of C16,
ˆ all solder connections.
Hints:
•
Frequency drift is usually caused by a weak battery or operation at large
temperature extremes.
•
Erratic or unstable operation is caused by faulty solder joints or cable
connections.
•
Standard 2SC2498 replacements: ECG10 or SK9139, may be found at
most local electronics parts dealers.