Troubleshooting The Ericotone
This section covers the problems that can
cause an Ericotone not to work. If you aren't handy with a soldering iron and multi-meter,
you might want to leave this work to someone who is. If you're willing to try anyhow, good
for you. At worst, you will only have to have someone else take over where you left off.
CAUTION: If you are testing a
ringing phone, don't forget that ringing voltage is about 100 volts. It doesn't hurt, but
it's enough to make you jump.
Electrical components prone to fail
There are four components most likely to be at fault for a non-functioning
The 3.3µf capacitor at the top of the unit. This capacitor is an
electrolytic that tends to dry out with age. Symptoms: light clicking sound instead of
tweeting or no sound at all and the neon tube continues to fire.
The transistor may either short out or go open, so testing is not so
easy. You may want to replace this as a last resort. Symptoms: light clicking sound
instead of tweeting or no sound at all, neon tube may still fire.The transistor in the
unit is no longer made, but can be replaced with a 2N4036.
The choke is probably the easiest to diagnose. Simply bypass it and see
if the ringer works, or any reading on an ohm meter is acceptable. Symptoms: ringer
Transformer. This item (not seen in the picture) is a part of the
chassis. Even though it may fail, the phone may continue to work. Symptoms:No sound and
the neon tube still fires. See the next section for more on this.
You will need an ohm meter for testing the transformer. Fortunately, you
can do this testing without having to desolder any connections (as long as the phone is
A(red) to B(white) = 125 ohms
A(red) to C(yellow) = 46 ohms
C(yellow) to D(blue) = 32 ohms
Any readings close to these is acceptable. These circuits are either good
or bad, there's no in between.