April 2011 Archives

I got my transponder from Dynon.  I purchased the high-power, class 1 SV-XPNDR-261.  This thing is nice and tiny, but still puts out 250W of transmit power.  It also meets the full ADS-B out requirement when connected to a TSO-C146A GPS (such as the Garmin GTN series that I'm going with).  It also displays TIS traffic on the SkyView which is handy around the areas I fly in.

I also received the ARINC-429 module.  This lets the SkyView interface fully with the Garmin GTN unit to get features like GPS steering for the autopilot, CDI autoscaling, and vertical guidance for approaches. 

I also purchased a second SkyView Display Harness.  I decided to purchase this separately so I can hold off on purchasing the second display until just before flight.  I can move my single display between sides on the panel when building the overall harness.  You can also see that I purchased a second panel mount USB cable.

I also received a second battery for the right display.  I can go ahead and mount this and connect it to the right display harness.

I also picked up two 30' network cables.  I'll cut these up to the custom lengths I need when connecting components.

I also picked up a hobbs meter from Aircraft Spruce.  Although the SkyView has a hobbs built in, I don't like the idea of having the only record of aircraft flight time being stored electronically.  If there is a failure or I have to send a display back for service, there is always the possibility that the total flight time is lost.

Misc Avionics Stuff

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I opened the new SkyView Display Harness and installed the panel mount USB cable.

While looking at the wiring diagram for the transponder, I noticed that there were a couple of loopbacks, so I installed these using some 22AWG wire.

I also got an order from Van's that included this pressure switch.  I installed it in. the right port of the manifold using an AN915-1 elbow.  This will drive both the hobbs meter (connected to the NO pin) as well as one of the annunciator lights to indicate low oil pressure.

I went ahead and installed a wire to the ground pin.  Since I don't have a ground block on the firewall side, I ran this through the pass through so i can connect it to the ground block on the cabin side.

I decided to go ahead and label the ground wires.  The labels are facing downward since I'll only be able to see this from below once the last skin goes on.

I have no idea why I didn't think of this before.  Since I have a label maker that will print on heat shrink tubing, I printed up some labels for my drill bits.  Trying to read these numbers on the bits themselves has come quite a pain.  You can also see that I put the screw/bolt size on the label as well so I don't have to look these up on a drill guide.

I installed the ARINC-429 module on the front side of the subpanel on the pilot's side.

I installed the backup battery for the left display on the back side of the subpanel.  Batteries have to be replaced from time to time, so I wanted these to be fairly easy to access.  With the tipup canopy open, these are easily accessible.

I also put a new terminal on the battery positive cable with a 12AWG wire for the battery bus.

I also installed a couple of adel clamps to tie the battery positive cable to the engine mount.  Without this, the terminals would have to carry all of the weight of this cable (and it can weight quite a bit when I'm pulling 6Gs).

The battery bus cable comes through the pass through and will connect to the battery bus via the bolt on the bottom.

The Dynon transponder uses a TNC connector instead of an BNC connector.  Fortunately, Fry's carries RV-58 TNC crimp on connectors.  I'm using RG-400 which uses the same connectors.  I crimped it on to the end of a piece of RG-400.  I'll cut it to length and put a BNC connector on the other end to connect to the antenna.

I was originally thinking I'd install the transponder and antenna under the passenger seat, but Dynon recommends at least 3' of separation between the transponder and COM antennas.  Instead, I decided to mount the transponder behind the baggage wall underneath the pitch servo.  The transponder clips to a mounting bracket that is screwed to the center rib just in front of the shelf where I'll mount the ELT.

Now that the EMS is in its final position, I cut the oil and fuel pressure lines and added crimp ring terminals.

I also crimped the connectors on the manifold pressure sensor wires and installed it in the MAP sensor.

Lastly, I installed the sensor wire on the oil temperature sensor.

I played around withe routing the shunt and fuel flow sensor wires over to the right side of the engine.  I decided to have them follow the Light Speed ignition sensor wire to where it mates up with the starter wire, then turn and follow that across the engine compartment.

Here you can see those wires follow the starter cable over to the connector.

They then jump over to the alternator feed wire.  The shunt wires separate there and will connect to the shunt just behind the left tube here.  The fuel flow wires follow the alternator feed wire forward to where the fuel flow sensor will be mounted.

I removed the fast-on tabs from the wires on the fuel flow sensor and installed some knife connectors.

I then installed the short fuel line between the fuel servo and the fuel flow sensor.  If you want to duplicate my setup, you'll need a 2.75" seat-to-seat hose with 1/4" straight-to-straight connectors and firesleeve.

The output side of the sensor has an identical fuel line, but 9.75" seat-to-seat.  It's a little hard to tell from this picture, but there's quite a lot of clearance all around the sensor.  It's only about 3" from the #1 exhaust pipe though.  The alternator wire is a little closer even.  I'll put a long heat shield along this section of the exhaust pipe to reduce radiated heat to these components.

Here you can see how the fuel hose makes a straight run up to the spider from there.

I then reinstalled the intercylinder baffle retaining  clamp (which was a pain in the ass).

I'm also using the knife connectors to connect the EGT/CHT wires to the EMS harness.  I got through part of the connectors on the right side tonight.

Here's a closeup of the #1 and #3 EGT connections.

The knife connectors interlock and form a connection that can't vibrate apart even under tension.  I'll put sections of heat shrink over all of these connections before finishing off the wiring bundle.

Since the knife splices aren't insulated where they connect, I slipped a piece of heat shrink over each connection.

I then put larger pieces of heat shrink over each pair to keep everything immobilized.  For some reason, the EGT probe wires are solid conductors instead of stranded like every other wire used on aircraft, so they need to be well supported.

I ended up turning my ground block vertical.  I'm really glad I held off on drilling the other hole in this.  I'm going to hold off as long as possible in case I need to order a larger one.  If I can use this one, I may turn it another 90º clockwise so that it's still horizontal.

Here's the reason I turned the ground block.  I installed the firewall wiring conduit per drawing OP-30.  This will be used to route wires front the front of the aircraft to everywhere aft of here.

The conduit follows one of the firewall stiffeners and goes through another adel clamp near the bottom.  It then steps inside the stiffener (where there is already a hole in the cover) and will go under the center floor cover back to the spar.

I pushed a piece of RG-400 through the conduit to get an idea how much space I'll have in the conduit and figure out how I'm going to route the wires.  There are going to be a ton of wires that have to run through this conduit:

    • COM antenna[s]
    • SkyView network cable
    • Transponder power, ground, and serial wires
    • Autopilot servo power/ground wires
    • Stick trim and PTT wires
    • Aileron and elevator trim wires
    • Landing, taxi, NAV, and strobe wires
    • Flap motor and position sensor wires
    • Cabin light wires
    • Seat heater wires
Geez, after listing all these, I can't possibly see that they'll all fit through the conduit (even though most are pretty small relative to the RG-400).  I'll either run the wires through the adel clamps directly and wrap the wires with split tubing, or possibly run a second conduit down the left side of the center section.

The wires exit the bottom of the conduit and will run along the floor.  I'll add anchors along the floor to keep the bundle secure.

The wire exits the back of the spar near where the elevator horn sits.  I'm not sure I like where Van's suggests you put the snap bushings in the ribs.  The wires have to make a fairly sharp turn to go through the ribs.  This is fine for all of the small wires, but the RG-400 has a minimum bend radius of 1", so that might not work.

Another possibility I've seen builders use is to cross the wires and penetrate the rib on the opposite side of the spar penetration (though obviously below the push tube).  I'd need to drill new rib penetrations which would be challenging given the spacing between the ribs.  This certainly allows a generous bend radius in the wires though.

I also ordered my interior from Classic Aero Designs.  I'm going with the aviator seats with headrests, side panels, and full carpet.  I also added in the hooker harnesses with matching leather pads.  This will be a relatively heavy interior compared with the minimal cloth interior that many builders go with, but I really want a completely finished leather interior.
I added up all the wires that will need to go through the conduit, and it was pretty clear that they weren't all going to fit.  I could either run a second conduit down the left side, or simply run the wires through the adel clamps directly and then wrap them with a split conduit which seems like the simpler option.

I decided to order a new center section cover from Van's.  If you recall, I had to move the electric fuel pump forward a bit because I couldn't easily fabricate the line from the fuel selector down to the fuel filter according to the dimensions in the plans.  This was going to require fabricating a custom fuel pump cover.  I was recently putting together my interior order, and the custom cover was going to complicate the floor carpet order.  I ended up deciding the easier thing to do was move the fuel pump back so that I could use the standard fuel pump cover (and hence the standard carpet).

I also played around with wire routing under the seats.  Van's stock location just isn't going to work.  The RG-400 would be right at the minimum bend radius and the wires have to get routed around the control stick mounts.  I'm going to have to punch additional holes in the ribs in the location I identified yesterday.

Finally, I ordered a couple of custom circuit boards today to control the annunciator lights and for the avionics interconnect.
After fiddling around with where to mount the fuel pump, I decided not to mount the fuel pump to cross bars on the center cover.  I did this for a couple of reasons.  First, It means that the fuel pump has to come out if I ever need to remove the cover fiddle with the wiring.  Second, the cross bars reduce the vertical space available for wiring under the cover.  Instead, I'm going to mount the fuel pump mounting plate directly to the floor.  I do need to be able to remove the fuel pump and controller if they ever need to be serviced, and I don't want to have to remove the mounting plate since that will require two people (one for the screws on the outside and one for the nuts on the inside).  To do that, I decided to replace all of the small metric nuts and screws with standard #6 AN hardware.  I installed nutplates on the bottom of the mounting plate.

I then used some short AN515 #6 screws to screw the pump and controller down to the mounting plate.  You can also see that I removed the terminal block and replaced it with a two connector molex connector.

Here's where the fuel pump will be mounted.  I'll fabricate some short spacers and the screw this to the floor.

Moving the pump down made it a lot easier to bend this fuel line between the fuel selector and the fuel filter.  There is tons of room around the fuel line, and plenty of clearance from the spar penetration holes for wiring.  This also brings the pump pretty far back which keeps it completely inside the pump cover.

Installed Fuel Pump

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The fuel pump needs to be spaced up off the floor a little bit because of the nutplates and protruding screws on the bottom of the fuel pump mounting plate.  I fabricated four aluminum spacers and countersunk one end of each so that it will fit over the dimples in the floor.  I didn't get any pictures of it, but I then dimpled the floor and installed the fuel pump with some scrap hardware.  I need to order some AN509-8R12 hardware to mount it for good.

I fabricated the fuel line that runs between the fuel pump and the firewall.  I had previously fabricated this line, but that was for the old pump position and that line would no longer work.  Despite the pump being farther back, this line is shorter because it takes a more direct route.

The line steps down immediately after leaving the pump to go under the cover and then bends slightly to the right to head directly to the firewall penetration.

I cut away a good chunk of the cover so that it can drop in over the pump.  This is so much better than old way I was installing this.  That would have required removing the pump to access the wiring bundle.  I bent a flange in the forward end of the cutout to stiffen the cover in this spot.

The line just touched the forward end of the cutout, so I used my dremel and sanded away a relief.  There is about 1/4" of clearance around the line now and nothing can flex that far.  I might still add some silicone wrap here though.

Here's what it looks like with all of the covers in place.  With everything in its final position, I drilled the cover to the holes that were already in the floor stiffeners

I pulled everything apart to install nutplates and prep everything for final assembly.  While I had the fuel selector mounting plate off the plane, I countersunk all of the screw holes.  I didn't realize until after doing this that the three holes near the fuel selector didn't need to be countersunk since there is a cover plate that mounts over this.  It won't matter though since these will be hidden under that plate.


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I riveted the pump cover to the fuel selector cover.  Some people use screws to attach these, but I can't see why you'd ever care to remove one without the other and rivets are simpler and lighter.

It's a little hard to see what this is, but it's a picture of the inside of the two pieces above.  I cut away most of the front of the fuel selector cover since the extra metal inside here served no purpose.

I also installed nutplates on the forward cover.  These allow the forward cover to be attached to the floor stiffeners as well as allowing the pump cover to be attached to the forward cover.

I cleaned the floor well and attached some adhesive tie-wrap mounts.

This is a closeup of the tie-wrap mounts.

I added loose tie-wraps to all of the mounts and then ran wires for the fuel pump.

The ground wire attaches to the firewall ground block and the power wire connects to the VP-X.  I'm really liking wiring with the VP-X since it allows you to do all of the wiring without having to have the panel design done or in the plane.  Once the panel is cut, I just need to run a sense line from the VP-X up to the switch and then the fuel pump wiring is done.

I received an order from ExpressPCB today with three PCBs that will be used to establish all of the interconnects between the avionics.  I installed 5 female DB-25 connectors in one of the boards, soldered the 125 contacts, and verified continuity between all the connectors.

Here's a closeup of one of the PCBs.  You can see that all of the DB-25 connectors are connected in parallel.  There are also extra solder pads between each connector in case there are components that need to connect various traces (e.g. resistors, diodes, etc.)  There are also even more extra pads off to the side that are unconnected that can be used for various purposes.  I don't think I'll need any of these features for my avionics interconnects, but I figured I'd add these in to make the PCB more flexible.

I figured I'd go ahead and name the circuit and throw a web address on there.  Since I ordered three, I have two extras for sale; let me know if you want one of them.  If there is enough demand, I may start offering these for sale.

Here's a closeup of the female DB-25 connectors.  I've got some 1/2" jack screws on order that will be used to anchor the connectors more firmly to the PCB.

I'll post a schematic later showing how these will be used, but the basic idea is that all of the serial and audio lines from the left SkyView screen will go to one connector and the serial and audio lines from the right SkyView screen will go to another connector (on the same pins since the SkyView requires they be connected together).  The serial lines from the Dynon transponder and GPS will go to a third connector (connected to the appropriate pins so that they can communicate with the SkyView screens).  The Garmin GTN-650 serial lines will go to a fourth connector to talk to both the SkyView screens and the transponder (to support the ADS-B out mandate).  The audio panel will connect to the final connector to get audio alerts from the SkyView and GTN.  I may also use this circuit to connect the dimming lines from all of the avionics.  This will be so much easier to wire and maintain than connecting all of the wires together directly in the harness.
I received my annunciator control boards from ExpressPCB.

Here's a closeup of the driver end of the circuit board.  I had to stagger the parts to get everything to fit with enough clearance around all the solder pads.

Just like the Avionics Interconnect circuit from yesterday, I threw a part number and website on these in case I start selling them.  I'm definitely selling the other two, so email me if you want one.  These can drive up to 10 annunciator lights triggered by either 12V or ground and include a facility for a push to test function and an external dimmer.

Here's the driver end of a populated board.  I don't have the PCB mount DB-37 connector yet which is why that isn't present.

Each annunciator light driver has an isolation diode to allow the push to test function.  The extra resistor is to protect the diodes against shorting one of the high triggers to ground.

I didn't forget to attach components here, these are plated through holes that allow these traces to connect to traces on the other side of the board.

Here's where those traces come through.  These route signals to the resistors driving the base of each transistor as well as the collector side of each transistor.  The emitters of all transistors are connected together and grounded.

I'm trying to wrap up the tailcone wiring before installing the rear window for good.  I fabricated a custom length SkyView network cable to go from the ADAHRS down to the pitch servo.  There will be a splitter mounted there that allows the ADAHRS and pitch servo connectors to join to the network cable that will be routed under the floor to the area under the pilot's seat.  To fabricate the splitter, I cut two short sections of SkyView network cable and installed one end of both sets of wires into a single male DB-9 connector.  It's pretty challenging, but you can install two 22AWG wires into a single crimp pin.  Getting all of the strands to slide into the pin before crimping is definitely a pain, but is doable.

I finished the SkyView network splitter I started yesterday.

I used one male and one female connector on the output so that there can only be one way to hook these up (not that it really matters since they're electrically identical).

I prepped the wires for the transponder harness.  The white wire has a 1.2kΩ resistor inline.  The wires overlap the resistor on each side to support the resistor.  I added a layer of heat shrink over the resistor after I took this picture.

I added the wires to the transponder connector.  The red and black wires are power and ground respectively.  The green and yellow wires will connect to one of the SkyView serial ports.  The white wire (under the heat shrink) will connect to the serial TX line of the Garmin GTN-635 to provide location into to the transponder.

Here's the connector attached to the transponder.  I'm generally avoiding using the thumb screws on DB connectors for weight reasons, but it would be pretty tricky to get a screwdriver on the the lower screw, so I used them here.

I ended up deciding not to use the splitter I built yesterday since it ended up introducing extra connectors for no good reason.  I still ended up with 3 pair of of DB-9 connectors since I split the servo power, ground, and Control Wheel Steering (CWS) line out into a separate connector.  I realized this was unnecessary, so I rewired this for the third time.

Now there are only two DB-9 connector pairs.  The SkyView network cable comes out of the conduit and into a female DB-9.  The male connector it attaches to splits out the two serial TX and RX lines into a second female DB-9 connector on the left.  The servo power, ground, and CWS lines come out of the conduit and also go into this connector.  Now there is only one male DB-9 for all of the servo attach wires.  The other wires coming out of the first male DB-9 connector (on the right) go up to the ADAHRS.

I added an adel clamp where the wires come out of the conduit to keep the wires from pulling on the conduit.

Here's the next bay to the right (where the pilot's stick goes.  There is a pair of DB-9 connectors here to provide another point for the network to split.  The red, black, and yellow wires are for the servo power, ground, and CWS wires.  The power and ground wires will connect here to another pair of wires that will run forward to the VP-X and ground block.  The yellow wires will connect together and go the CWS button on the pilot's stick.

I also used the thumb screws here since it would be a pain to get a screwdriver on these screws.

The next bay to the right of that contains the two output connectors for the splitter in the previous bay.  I used one male and one female connector here since these aren't electrically identical.  The male connector is a standard SkyView network connector and it is connected to a cable that runs up behind the instrument panel.  The other side of the splitter (the currently unconnected female DB-9 connector) only contains the two serial TX and RX lines as well as the servo power, ground, and CWS lines.  Another connector will attach here and go out to the right wing to hook up to the roll servo.

I also added another adel clamp to help stabilize the wires where they cross under the elevator push tube.

I hooked up the transponder power and ground wires.  You can also see the yellow, green, and white serial lines as well as the SkyView network cable routed through here.

I fabricated and installed the cable to the roll servo in the right wing and hooked it up under the pilot's seat.

I ran the wire under the passenger seat and coiled the wire in the outboard bay.  I'll drill the hole and then pull this out to the servo when the wings are attached permanently (or add a connector in the wing root; I haven't decided).  I previously ran some servo wire in the wing that I bought from SteinAir, but I'm going to swap that out for the harness wire I purchased from Dynon.  I'd like to keep all network wires the same color throughout the aircraft so that it's easier to maintain things down the road.

I received an order from L-Com today with a bunch of additional connectors, shells, etc.  I installed the female DB-37 onto the annunciator control board.  After installing this, I hooked up a couple of annunciator lights and the dimmer and verified I could trigger the lights on both high and low signals as well as verified that accidentally grounding the high trigger or putting +12V on the low trigger had no effect.  Everything tested out perfectly.

I also installed some longer jack screws in the connector.

I soldered the other side of the jack screws to the circuit board to provide some additional support to the connector.  This thing is very strong now.

I also installed jack screws in the avionics interconnect circuit and soldered them to the board.  These circuits are ready to install.

Worked on Power Wiring

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I got an order from Aircraft Spruce today with some 6AWG wire, so I fabricated the wire from the output side of the alternator current limiter to the Vertical Power VP-X.  Here's the alternator current limiter end of the wire (protected by the boot).  All of this metal down here is hot when the master contactor is closed.  I need to research if it is necessary to shield all of this in case something were to inadvertently connect any of this to ground.

Here's how the wire is routed up to the firewall pass-through.  You can see that the wire to the battery bus (the one that forms a U shape right in the center of the picture) also follows this wire up.  Behind the VP-X wire is also the alternator field wire.  I'll be installing a few more adel clamps and some high-temp zip-ties (replacing the cheap zip-ties currently installed).

Here's where the main VP-X wire comes through the firewall and drops down under the subpanel support rib through an additional adel clamp I installed just for that wire.  Being 6AWG, it's fairly heavy (especially when pulling 6 Gs), so I want it well supported.  You can also see that I installed the main battery bus with some hardware that also showed up from ACS and connected the battery bus supply wire.  You can also see the alternator field wire (the small white wire in the upper right) has been cut and connected to the voltage regulator.  Finally, I connected the voltage regulator ground wire (the black wire in the upper right.  I could have taken a short-cut through the rib lightening hole and made the wire substantially shorter, but I'm trying to keep all the wire bundles neat and organized instead of running them haphazardly around the plane.

The VP-X supply wire has a short straight shot from the bottom of the subpanel support rib to the VP-X power post.  I installed a boot on this end of the wire as well.

I wired up the voltage regulator (except for the wire going to the annunciator control circuit for the low voltage light).

The two power lines (red) are connected to separate pins on the VP-X.  The larger (18AWG) wire on the top provides power for the alternator field.  The voltage regulator takes power from this wire and sends it out the white wire to regulate the alternator. 

I installed the second SkyView battery on the right side in the same spot as the one on the left.

I also laid out when the radios will penetrate the subpanel, then installed the custom circuits on either side of that.  The IC-25 Bus is on the left and the AN-1 Annunciator Control circuit is on the right.

I fabricated 1/4" aluminum spacers to keep the back of the circuits from contacting the subpanel.

I measured where the SkyView connectors will sit on the back of the panel and taped them in place so that I could start wiring them.

I separated out all of the wires and labeled them.

All of the wires from the right SkyView display that need to connect to the bus will reach across the panel.  They will need to be run across the top of the audio panel and through the two panel support ribs.  I can't run any of these now since I don't have the radio stack yet.

I received my capacitive fuel senders from Princeton Electronics.  They don't have a website, but you can reach them at (616) 243-8800.  They have both 2 level and 5 level senders.  Both convert the capacitance range from 0-5 volts, but the 2S model only has calibration points for empty and full.  The 5S model has three intermediate points which is important if you want a linear movement on an analog gauge.  Since I'm using the SkyView which has numerous intermediate calibration points, it doesn't matter if the sender is linear or not, so I'm just using the 2S sender.  I cut most of the wires off and installed some four position molex connectors on each sender so that they can be easily removed if necessary (well, except for the cable with the BNC connector).

I installed the senders on the aft side of the subpanel since they need to be accessed during calibration.  This is the left sender.

The right one is in the same relative position.

The cable to the fuel tank will get routed down the vent line, but I'm leaving it loose for now until I nail down the overall routing.

I drilled 1/4" holes just above the vent bulkhead fitting and ran the cable with the BNC connector out through it.  This will get connected to the BNC fitting on the fuel tank which is wired up to the capacitive plates inside the tank.

I finished up the fuel sender wiring by running some wires from the other side of the molex connector.  The red and black wires go to power (VP-X) and ground respectively.  The striped wire is the included wire from the EMS running directly from the necessary pin.

I'm using a single pin on the VP-X (J8 connector) to power both senders.  The wire comes out of the connector and through the adel clamp on the right.  I then used a solder sleeve to split this wire into two: one that runs directly forward to the left fuel sender and one that goes through the left adel clamp and across the plane to the right fuel sender.

I grounded the two fuel senders as well as both SkyView screens (the two twisted pairs of the wires).  I'm down to 11 available spots on my grounding block which seems pretty tight.

I was down to just a handful of unconnected wires on the EMS, so I decided to finish that off tonight.  Two of the wires ran to the fuel senders.  One more ran over to the annunciator control circuit (not connected yet).  Another ran forward and will connect to the left ignition switch to get an RPM reading from the magneto.  Finally, I hooked up the low voltage RPM pins to the Lightspeed Ignition to get a second RPM source.

Here's a closeup of the Lightspeed Tach line coming into the DB-37 connector.  It's a shielded 22AWG wire.  I split the shielding out and put heat shrink over if and the split point and wired the center conductor to pin 35 and the the shield to pin 16.

I received some interior lights from pilotlights.net.  They were great to work with and even through in a couple of small bonus products with my order.  I'm trying to use all dual color (white/green) interior lights.  From the research I've done, everyone is moving away from the old standard of red for cockpit lighting at night.  Although it did fine at preserving your night vision, it makes reading maps really hard.  The military has moved to green, but research has shown that a really dim white light is actually best for preserving night vision while still giving you the best visual clarity.

Here's the LED light strip I'm going to use under the glareshield (this is the 12V, high-power, dual-color white/green strip).  This is with just the white LEDs illuminated at full power.  It's hard to capture with a camera, but this is definitely more light than you'd need in a cockpit.

Here it is with just the green LEDs illuminated.

And here it is with both (although I'm not going to wire it in the plane with the ability to light both colors at the same time).

Using one of the PWM dimmers (also from pilotlights.net), you can dim the light down pretty far, but not quite far enough.  A dropping resistor of 150Ω or so makes the range just about perfect.  You can dim almost down to off and the brightest setting is still plenty bright.

Here's the PWM dimmer I'm using.  I bought three of these to replace the ones I purchased from periheliondesign.com.  The more I played with those, the less I liked them.  The lights flickered as you ramped up and down through the brightness range and putting the resistors to cap the low and high voltages wouldn't expand the range of the dimming knob which means you would have to turn the knob a bit before it would come off the low dim setting and you'd hit the bright setting long before hitting the upper end of the knob's range.  These PWM dimmers ramp smoothly across the whole range of the knob.  They also come with a much nicer machined aluminum knob instead of the plastic one on the dimmer from periheliondesign.com.

I also picked up this little four LED white light.  I'm going to put a dropping resistor on this and use it to cast a very dim light in the footwell.

I also went ahead and hooked up the four SkyView power wires to various pins on J10 and J12.  Each SkyView has one power wire going to bank A and one going to bank B for redundancy.

Wired Flap Motor

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I ran the wires to the flap motor tonight.  I put a two position molex connector on the wires so that the motor can be easily disconnected if it needs to come out.  There will also be a second connector here for the three pins from the flap position sensor.

I cut away a chunk of the forward end of the aft tunnel cover (basically the part that will be inside the flap motor housing.

This lets the wire that runs down the flap tunnel pass through the rear spar before coming up behind the flap weldment.  All of this will be secured by some wire tie mounts to keep it from coming in contact with the weldment.

I'm working quite a lot of hours at work now, so I'm not getting much time on the plane, but I want to make some progress on the plane every day that I can.  Since I got the flaps wired up last night, I decided to wire up the flap position sensor tonight.  These will be the last wires that need to run down the center tunnel.  I installed a three position molex connector for the position sensor.  I'm still not sure how I'm going to anchor these to the rear cover.

I didn't want the wires from the position sensor to rub the screws that attach the side covers to the flap housing, so I used a small drop of E6000 to secure the wires to the side of the position sensor.

I also swapped out the four position molex connectors on the fuel senders for three position connectors.

I attached the two flap wires to J12, pins 5 and 6 (the lower left red and black wires).

And the three flap position sensor wires to J1, pins 17, 18, and 19.

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