MFJ-8100K Manual

See the conclusion of this book for information on getting more information!
In Case of Difficulty
Your receiver is designed to work perfectly as soon as correct construction is completed.
Let's review those 5 possible building mistakes which will cause your receiver not work:
1. Installing a WRONG part.
Example: Using a 10 ohm resistor in place of 10K ohm(10,000 ohms)
2. Installing certain parts BACKWARDS.
Example: Reversing the (+) and (-) sides of an electrolytic capacitor, or pointing the
flat side of a transistor in the wrong direction.
3. Faulty SOLDER connection.
Example: "cold" connections or solder "bridges".
4. OMITTING a part, solder connection or wire.
Example: if it's supposed to be there and isn't, we have a problem!
5. Positioning the part close to the board prevents interaction with other parts.
If your receiver does not work, review all construction steps carefully. Let somebody else
go over your work and the steps.
Following are minor problems which are easy to solve:
One band seems identical to an adjacent band.
Check the soldering of all the inductors.
Extremely weak volume on all bands.
Test your headphones on a personal stereo and compare them to one or more other
headphones. It is very possible for inexpensive headphones to become defective. Also,
make sure that the battery is in good condition.
Steady, high-pitched squeal or whistle.
Regeneration control is turned too far clockwise.
Regeneration inoperative on some bands, especially D and E.
Incorrect adjustment of trimmer R20. Review Sections 5. If regeneration was previously
fine but now no longer works, the probable cause is a weak battery.
CW signals all sound chirpy or wobbly.
Replace the battery, it is too weak to operate both the regenerating detector and the audio
amplifier.
Receiver works fine sometimes, but is erratic especially when it is bumped or
moved.
Look for a loose solder connection.
34