Matt's RV-7 Project

I've just been adding one wire after another, making a little progress with every work session. This is one of the two big connectors on the GSU 73, specifically the one that includes most of the engine/airframe analog and frequency inputs. Man, these high-density connectors can be tricky to deal with. The bundle of short wires pointing to the right is a collection of pigtails for all the shielded wires, which will eventually be affixed to the connector backshell. Just visible coming out of the D-sub connector is the harness for the config module, which is a little EEPROM device that backs up important calibration settings.

I keep checking little wiring jobs off my to-do list… here's the magneto P-lead. The magneto switch is upside-down, since closing the switch equals "no spark".

Here's the power and oil pressure connections to the Hobbs meter. I know I don't really need a mechanical hourmeter since I have all this fancy electronic stuff to keep track of the airframe time for me, but I feel better having something that absolutely cannot lose time; I had a bad experience with another vendor's EIS product once upon a time.

Forward of the firewall, the wiring for the engine sensors is just coiled up, since I have to finish the cowl and baffling before I can hook things up for good.

More splicing, crimping, soldering, et cetera. This photo shows the wiring for the tach sender and fuel flow transducer:

I also finally got around to uploading a new copy of my electrical system schematic:

Finally, a warm weekend! After taking care of yard work and bills and house maintenance, I still had an entire afternoon to spend in the garage. I did a bunch of cleaning and straightening up, and then finished the last of the wires that runs to the lower connector on the GSU 73 ADC/AHRS/EIS unit. The upper connector is for all the various engine sensor inputs, which I'll begin hooking up soon enough.

Some of these connections need to be spliced six ways to sunday, and you have no choice but to do it right there on the airplane. A helping hand tool is indeed quite helpful for this. Note the heavy heatshrink on the jaws to protect the wires.