When I transmit on a VHF radio (even handheld 5 feet away) with my
Garmin 188C the sonar may cut out completely or the water temp increases
significantly (15+ degrees). Also the voltage drops by .6 volts. Has anyone had similar problems and if so have you had any success with Garmin and their service?
Cooker
12-16-2002, 11:21 AM
What may be happening is that RF power from the VHF is coupling into the power line to the LCR. The voltage reading is the DC value and there may be noise on the line that, under certain conditions, causes a power interuption long enough to turn the unit off. Additionally, the temp sensor is most likely a thermocouple that relies on a reference voltage. If the input voltage is noisy this may inpact the reference voltage and cause the temp fluctuation. A couple of things that you may be able to to is 1) shield the power cables (ie route from the battery to LCR in a piece of metal conduit or 2) electronics stores (ie Radio Shack) sell noise filters that are typically used to eliminate noise from a car engine from getting into the AM radio. This filter could be inserted just prior to the power connection to the LCR. I would probably try #2 first.