The white wire does not go to the servo. The green wires do. One comes from the servo, the other goes to the upper helm station tachometers. I'll measure them next.
From: Doug Thomas [mailto:[email protected]] Sent: Thursday, July 7, 2016 5:51 PM To: '[email protected]' Subject: tachs Both Datcon tachs on my Uniflite stopped working simultaneously. The servos are turning at the engine, so a signal should be available to the tachs. Power also seems to be available at the tachs. The backlight is on and I measure 14.5v at the terminals on the back of the tachs. The tachs have 4 terminals with a number of wires to each. Seems over complicated to me, but there it is. Facing the back of the tachs, I see 1 white to the lower left terminal, 2 green to the lower right, 2 black to the upper right and a black and 3 reds to the upper left terminal. My uneducated guess is that the upper right is GND and the upper left is positive power. I'm thinking the single white on the lower left is the signal source from the servo. This leaves the two greens on the lower right as complete unknowns. Measuring voltage on the across the single white wire to the terminal, I get 6 mV when I turn the ignition key on. I get 20 - 27 mV when I start the engine. However, nothing is displayed on the digital readout and the 20-27 mV is constantly varying at a constant RPM. Also, revving the engine seems to have no impact on the voltage. I cannot find these tachs anywhere on the web. Does anyone have any idea what can be the problem? Are my guesses correct? Doug -- You received this message because you are subscribed to the Google Groups "UnifliteWorld" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/unifliteworld. For more options, visit https://groups.google.com/d/optout.
