Electrical Gremlins Showing their Ugly Faces

[molson309]

Originally Posted by Slane

I'm not at all comfortable at reading electrical diagrams and so maybe the answer to my question is there, I just don't know how to read it. Here's the question: When I press my mic button (PTT), my EGT displays start doing the pogo-stick imitation and jump up and down. This is true for either the pilot or co-pilot. When the PTT is released, the jumping stops and the EGTs read normally. I have the pre-08-25-11 wiring harness for the Skyview.

I've needed to replace both EGT probes some time ago and have experienced good performance since.

When I study the electrical schematic, I see no reference to EGT wiring and could use the help of this group to know where to go next.

Thanks in advance.

Scott

Sounds like RF from the transmitter is getting into the wiring. Often this is caused by bad antenna SWR. Bad SWR can cause the coax cable between your radio and antenna to radiate RF power into nearby wiring, potentially causing all kinds of weird problems, and it's also not good for your radio.

I had a similar problem in my RV-7A with the same symptoms as yours, and it turned out to be a badly installed BNC connector at the antenna end of the coax cable. The center conductor was shorted to the braid on the antenna end. Installing a new connector fixed the issue.

Others have had bad SWR because of a badly grounded antenna.

Just making sure there's continuity from the center pin at one end to the center pin at the other, with no connection between the center pin and the outer shell can tell you a lot about whether the coax cable is bad. And inspect the center pins to see if they're as far forward as they should be. Also test continuity while flexing the cable at the connectors to see if you have a short/open that only happens when the cable is in a certain position.

One other diagnostic is to see if transmitting on a handheld radio nearby causes the same problem. You might just have electronics that are overly sensitive to RF. In this case a talk with the manufacturer might get you resolution.

Good luck!

[jliltd]

Okay. Somebody has to say it. So I am going to say it. The Emperor is not wearing any clothes....

Gosh. Makes me miss the "olden days" when we timed two mags and then went flying for a year. I am starting to hate all manner of electronic engine instruments and their persnikity sensors and connectors. It never ceases to amaze me. EI. JPI. Insight. Dynon. Garmin. 9 times out of ten the problem is with a sensor or a connection. Meanwhile you scare the bejesus out of your passengers with the danger annunciations in the headsets. Think of the robot in "Lost in Space". Danger. Danger Will Robinson. Danger. Sheesh.

Remember when we had pressure lines connected directly to bourdon tube gauges that couldn't care less if there was a battery or an overly sensitive metrosexual sensor and voice who felt as if it had been insulted by a loose ground? The "olden days" engine gauges were super reliable and simple. The FAA likes the newer electronic versions of engine instrumentation without oil or fuel tubes or thermocouple wires passing through the firewall for "safety reasons". But with all the false and annoying annunciations in your headsets the true reason for the new fangled stuff improving safety becomes clear. It truly IS safer when you give up flying all together after you've had enough of your airplane's Bichin' Betty telling you you're GOING TO DIE every time you want to enjoy a nice peaceful flight on a perfect day. Much less having the nervous spouse on board listening to all that. You try to convince them everything is actually just fine. Remember you can't fool the one who washes your whitey tighteys.

For anybody who might get the impression I am an anti-technology unibomber type, rest assured that I am an electrical engineer and aerospace design engineer and technology and gadget freak. To the degree of an early adopter. But my enthusiasm for electronic aircraft engine monitoring has lost it's luster. Life was so much easier before Betty and the boy who cried wolf. I am confident that digital engine monitoring will improve over time but we really need to fire Betty. Now. Look at the example of audio intercoms. They used to all mute background music whenever a passenger or pilot broke intercom vox or the radio receiver got a transmission. That was super annoying and distracting. After years of annoying interruptions to the normal human hearing pattern and brainwave activity most new intercoms and audio panels provide "karaoke mode" wherein the music audio and/or radio or ICS traffic is heard at the same time. Surprise... that is just like real life and how our brains are wired. Automute, or soft mute or whatever the first clever audio engineer came up with in a "stroke of genius" was in fact a human factor failure. In the first degree. There is nothing more distracting than a constant interruption of a normal sound pattern. I think the same is true for the current crop digital engine monitoring with their suspect sensors and non fool-proof connectors highlighted by a little voice nagging the pilot about any little thing that comes along. We wouldn't put up with a snooty passenger bugging us continuously throughout a flight so why do we put up with or robotic Betty without firing her? Heck, in fact we paid thousands of dollars to hire Betty with her annoying voice. I thought my ex was on board the first time I heard "the voice" I contend the combination of flaky non-standardized sensors and connectors with a bichin' betty voice actually makes things less safe than the "good old days". Nag nag nag. What is more distracting than THAT on short final? Right?.... Right.

Remember in the semi-Renaissance "good old days" when your stupid GPS navigator would annunciate "arriving at destination" when you were over the numbers trying to land? No sh** Sherlock. Shut the f** up already. I am try to concentrate on my landing you piece...

Maybe a Dynon or Garmin PFD and/or MFD, minus EIS sitting along side legacy engine gauges is the new Rennasaince.

Jim The Rennasaince Man
Shut the f*** up, you... voice you

[D&M Dan]

Wondering if any of you can help me debug my SV Network Status as it appears some have gone before me with this problem. I have been getting a sporadic Standby Network Error. The roll servo goes offline occasionally also. Could be a poor connection at the roll servo, but before tearing out panels, wondering if anyone else has experienced this.
In the Network Status Page this is what I see in yellow,
1: SV32/SV42/SV52 Serial:0058890 SW Version 14.2.1.3698 - Status Ready
Skyview Network Connection Fault-Data 2 Pair (Pins 4&8)
2: SV32/SV42/SV52 Serial:005561-SW Version: 14.2.1 33698 - Status Ready
Skyview Network Connection Fault- Data 2 Pair (Pins 4&8)
Yes, I know I need to upgrade my SV Version. Todays project.
Thanks for any input.
Dan