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Back to it: ELT and radio stack.

August 22, 2011 / posted in Panel / No Comments

4 hours.

Finally got back into it today. First thing I did was dismount the EFIS in preparation for making a hole for the ELT remote switch. Then I reinstalled the radio trays back in their spot so I’d have a stiffer panel to work with during the process of making the hole. I still need to figure out where the ELT wire’s going to make its way to the panel. Oh, and I realized I need another roll of 3-conductor shielded wire, because I also have to get GPS data back to the ELT as well. I guess it transmits the last known position while it’s screaming for help.

I need to start finishing things in the back of the baggage compartment, because not only am I tired of crawling around back there, I need to not have that to worry about while I’m finishing up the wiring.

I also have some 4-40 screws on order from ACS, because the ELT kit doesn’t actually provide any. I also have a BNC-terminated antenna on the way.

Wiring harness done. I think.

August 8, 2011 / posted in Panel / No Comments

10 hours.

This is what I wound up with at the end of yesterday:

It might look like a mess, but it’s not. Every pin in every connector has been checked twice, and the coils are grouped by device and function. Except the one or two I missed. This has been an exercise in patience and squinting at little wires. It’s like everything else in this project: If you look at the whole thing it looks insane and impossible, but if you look at it one piece at a time, it’s not that big a deal.

Each wire only has two ends, so that makes a good place to start. First I did all the power and ground connections. There are several. The 430 has 3 devices in one, but only two have their own power feeds, unless I’m driving a superflag device off the NAV unit, which I’m not. The audio panel is the hairiest part, because there are so many connections and a couple of them share pins, which sucks, because you have to make pigtails that combine two wires, usually audio returns, into a single pin that plugs into the connector. The shields absolutely suck. I probably should have used 24ga wire, but I had green 20ga wire, so I used that. That’s where I learned the Aeroelectric (and probably standard) way to bridge shield to a standard wire. That wasn’t that difficult, but there were a lot of them, and now they’re all ganged together and fastened to the audio panel’s frame. The deal is, you ground the shields at the audio panel to reduce noise, or at least attempt to do so. Supposedly this is how you keep EMI noise out of your audio connections, which tend to run all over the aircraft and often past some noisy things like strobes, relays, etc. Now, hopefully, in crushing together all those cables, I haven’t compromised the insulation integrity, and during the soldering process, didn’t melt through any signal wires. I still need to verify connectivity and isolation, but I’m off to Vancouver for SIGGRAPH, so that’ll have to wait.

I couldn’t just leave it be, though. I powered up the audio panel, which lights up fine, but I didn’t want to risk powering up the radio. If something is screwed up in my wiring and the mic key is stuck on, the RF power with no antenna will fry me out of $7500 worth of radio, GPS, and NAV equipment. Not to say I didn’t try. I had some leftover RG400, which I put a BNC end on, and was going to connect the other end to my COMM antenna, but that didn’t happen. RG400 cable has two layers of shield on it, so the usual trick of pushing the shield down and pulling the wire through doesn’t work. My current RAMI antenna needs pigtails for wiring, and dammit, so does the marker beacon antenna. So I need a COMM antenna that uses a BNC connector like everything else.

One thing I missed while I was wiring is the COMM remote recall function. This uses a discrete input (fancy name for an external button) to scroll through a list of preset frequencies. It looks almost useful enough to take apart the main connector on the GNS430W and add a tail for it, but I don’t actually have a free button for it. If I didn’t do remote ident on the transponder I could. The other suck part about the GNS430W is that it doesn’t have the same remote function protocol as the SL30, which can be fully controlled via RS232 communication. Sure would be nice to be able to set frequencies from the EFIS, but this setup will be fine as is.

I also got a phone extension cable to make up for the shortcomings of the one shipped with the ACK 406 ELT, which doesn’t quite reach all the way to the panel after threading its way through the wire bundle. I also figured out how to install phone cable ends, a skill useless in every other facet of life, since I don’t even have a landline anymore and subsequently will probably never wire a phone jack in this house. The new cable, with the end cut off, goes fine through the portholes I drilled for the strobe cable. Yes, I know it’s probably bad, but as long as the strobe noise doesn’t trigger the ELT’s emergency transmit mode, I can live with it.

When I get back, I’ll also have to dismount the EFIS to install the ELT remote switch and verify GPS communication. Then my time in the tailcone is DONE. I’ll reinstall the flap arm and the flap motor and call it a day.

The other thing I have to do is run another wire for push-to-talk on the pilot side. The audio panel has facilities for multiple push-to-talk sources, diagrammed by shorting the PTT circuit to the MIC return, which is the same thing as shorting it to ground. Right now, I have both PTT buttons coming out of one wire, and I need two, one for pilot, one for copilot.

I also need to lay out my wire codes on here so I have a record of them.

Phone cables suck.

August 3, 2011 / posted in Fuselage, Panel / No Comments

2 hours.

I don’t know whose brilliant idea it was to use terminated 4-conductor phone cable for the ELT’s GPS data, but they should be kicked in the groin until they pass out. First, the ends don’t fit through the pass-through holes in the bulkheads so the cable can get from behind the baggage compartment all the way up to the panel. Second, the cable provided is too short, by about 5 feet. Third, the end connectors are single-use, and taking them apart (to run the cable through bulkheads) pretty much destroys them so you can’t use them again.

After utter failure on that front, I went back to wiring the avionics stack. It’s progressing nicely. Still, Shelley commented that it looks like C-3PO had diarrhea all over the shop, indicated by this shot:

The GMA340 audio panel is a wonderful thing. Not only do I have inputs for music, 4 radios, various navigation equipment, and an antenna. I also have an altitude warning audio input. I need to do some research, but that seems like the logical place to run EFIS audio. So far I’ve got almost everything half-connected. The next step is to connect the devices together and make nice wire bundles per AC-43.13 or whatever it is. I’ll be using zip-ties, because as cool as lacing is, I want to get this done fairly quickly.

I’m about to bugger off to Vancouver for a few days for the Gathering of Geeks known as SIGGRAPH, so I’ll probably be out of the game until next Friday, but if I can get some stuff done this weekend, I will.

Avionics harness continued.

August 1, 2011 / posted in Panel / No Comments

7 hours.

That’s 3 yesterday, 4 today.

The two biggest challenges for me in this wiring harness debacle seem to be keeping good records (which colors go where), and puzzling out the connections between pieces of equimpent. The GNS430 and GMA340 have way more options than I’m ever going to need. Most of the 430’s outputs are for various navigation instruments that I don’t have, and the audio panel has options for 6 passengers and various pieces of navigation equipnent like DME and ADF, neither of which I will be using. The 430W to EFIS connection is dirt simple, six wires and the EFIS makes use of the ARINC429 data feeds for fully legal IFR navigation. The connectors themselves, however are quite intimidating. The 430W has 3, two of which are high-density d-sub connectors, but very few pins are actually in use.

But the key is to take good notes. I’ll post my wiring system here next chance I get, but I’ve basically set it up this way:

For mono audio, White is HI (+) and white/blue is LO (-). For stereo audio, White is return, white/orange is right, white/blue is left.

I wrote something down for the ARINC and Mic connections, but I don’t remember it offhand. It’s important to take notes, because when the backshell is on the connector, you can’t see the wire colors anymore. I’m sure this is old hat to you avionics experts out there, but my experience runs more toward DJ and club sound systems, MIDI keyboards, and computers, so this is indeed different.

I also make my first shield ground pigtails today. This is the Nuckolls method. You strip off the insulation on the shielded cable, then cut the shield back so only 1/4″ is left. Then you make a 22ga pigtail. On this, you strip off about 1″ of insulation, then unwind 4 strands, then cut the rest of the wire off to 1/4″ of length. Lay the 1/4″ of wire along the 1/4″ of shield, then wrap the strands around both. Then flow a little solder into the connection, cover with heat shrink tubing, and done. This is how all the audio panel connection shields are grounded.

Shields are all grounded at the audio panel, because that’s the best way to eliminate noise.

OH, and for some reason, I seem to have the worst luck with all the litte attachments for my d-sub pin tool. I’ve already mangled the lo-density attachment, and today, I managed to get one caught in the mechanism of the AFM8 crimper. Freak accident. But fortunately it wasn’t an attachment I’ll need for this project.

OK, just one more thing.

July 24, 2011 / posted in Firewall Forward, Fuselage, Panel / No Comments

2 hours.

Relabeled antenna wires, applied thread seal to brake fittings (yeah, stupid, I know, shoulda done it back when I installed the brake pedals), and installed sensor manifold fittings. Little things, you know, they add up.

More avionics wiring.

July 24, 2011 / posted in Panel / No Comments

6 hours.

That six hours includes both avionics wiring and mounting the phone/mic jack tabs to the bottom of the panel. The day didn’t start out so great. I’m missing a tool and some wire. The tool is a Daniels K42 positioner. It clips into the AFM8 crimper so that when a wire with a d-sub pin on the end is inserted, it crimps at exactly the right place. I have the K13-1, which is great for standard density d-sub pins, but everything in on the GNS430W and the audio panel are high density d-sub connectors. These puppies are spendy, I can tell you that. Little device about the size of a lug nut will run you $65 new from SteinAir. I found one used on crimptools.com for $25. Hopefully it’s not trashed.

The wire is 2-conductor shielded 22 gauge. This runs all over the place connecting audio from and to various devices. I have some single-conductor left over from the mag wiring, and I have some 3-conductor I bought a long time ago, but no 2-conductor anywhere.

I did manage to get aircraft power and aircraft ground wired into the COM connector. One’s for transmit, one’s for receive, I guess.

At that point, I figured I was done wiring, so I trimmed and painted my panel extension tabs for the mic and phone jacks.

They actually look OK. I noticed that from the side, you can see the wiring tabs on the backside, but there will be black shrinkwrap tubing wrapped around them, so you won’t really notice.

Both sides seem OK.

Then I threw on the Synthpop/Futurepop stream on di.fm and started going over the 430W installation manual. Handily enough, there’s a diagram in the back, page H-4, I believe, that shows the interconnects between the 430W and the GMA340 audio panel.

The Mic audio connection uses a 3-conductor shielded wire, so I was able to wire the 430W end of that.

This’ll probably be my last entry for a few days. Going to MI to see my dad. When I get back from my trip, my K42 and my 2 conductor cable should be here, so I’ll be able to finish the harness and plug it all in. Then we see if I can catch tower and ground at SMO on my newly installed stack.

Avionics wiring begins.

July 22, 2011 / posted in Panel / No Comments

1.5 hours.

Finally, all the bits and pieces are here. I have my connector kits for both the GNS430W and the GMA340. That bloody connector kit for the 340 is $75. Truly the aircraft premium applies. But the folks at SteinAir shipped it out as soon as it came in, and by the way, SteinAir is an excellent company to deal with. They are personable, know their biz, and have just about everything you need related to avionics.

So I started out by mocking up the protrusions of the trays, with blocks of wood, measured and cut to match the shapes of the equipment, with the intention of just fastening the backplates to the wood blocks and not having to pull the trays out from behind the panel. After a while, I realized that was a stupid idea and the time to dismount the avionics trays would be less than making and setting up a mockup. So now it’s on the bench, ready to rock.

Maybe the clecos holding the D-sub connectors in there are a bad idea, but it’ll work for now. I need to print out a GMA340 manual so I can have it nearby with my GNS430w manual when I do the interconnects. This whole process shouldn’t take more than about two days, but I don’t want to jinx it. Plus I’m going out of town for a couple of days next week, which won’t help. Then I have to go out of town again the 2nd week in August. I need to get this avionics business done because I need to start working on the cowling. And order my interior. And my prop governor.

Jackholes.

July 19, 2011 / posted in Electrical, Fuselage, Panel / No Comments

1 hour.

No, really. Jackholes. For the Mic and Phone jacks. I fabbed up two plates for mounting the headset jacks and drilled two 1/2″ holes in each one. Each plate is a piece of .063 bent 90 degrees with about an inch and a quarter of metal on each side. This will be riveted to the panel where it bends horizontal at the bottom. This should give me enough room to move around, but we’ll see. If I catch a knee on it, I’ll have to think of alternatives.

The week in review.

June 27, 2011 / posted in Electrical, Fuselage, Panel / 1 Comment

20 hours.

Yes, I know I’m supposed to keep track of this on a daily basis, but I really didn’t get a lot significant done until today, just little bits and pieces here and there, tasks taking less time than actually making one of these blog entries. Even so, the last month has been a wash. The EFIS was in the shop, work went crazy on me and I had to go out of town for a few days on a pre-planned vacation, and I just flat out lost my mojo. Let me tell you, working all through Memorial Day weekend sucks big time, and I haven’t had to do that in years, even in production. But now with two working knees, and all the fiddly bits I’ve needed finally coming together, I’m in a good place. It all started with a good shop cleaning. A couple of weeks ago, I hung up the control surfaces on the walls, in an attempt to de-clutter the work area, and this worked out brilliantly, so much so that I can actually test the trim wiring with the elevator hanging on the wall near the tail. But the workbench was a blast zone. Shipping materials alone accounted for a good half of the mess, tools and hardware the other half. Yesterday I put things away and recycled boxes and got most of my workspace back. Then it was all about knocking down all the dominoes I’d been setting up for myself over the last couple of months.

At one point I got the control stick wiring all done, thinning out the bundle in the big blue casing so I could actually work with it. Here I am, happily wiring away, combining all the ground wires into one, reducing the bundle of wires from 17 to 10. This is wrong. More on that later.

The replacement pax stick came in, and I managed to cut it and drill it without incident, but I’ve come to the conclusion that working with steel sucks. I’ve been picking little slivers of steel out of my hide for two weeks now.

When we got back from vacation in Yellowstone, I found a package from Infinity Aerospace waiting for me: my 3-circuit relay deck, which handles 2 axes of trim and flaps. Here it is being fitted for a stand so it can sit in between the middle seat ribs:

It also included the spacer necessary to fit the Infinity stick grip to a 7/8″ tube, which is the OD of the pax stick. Here’s the pax stick installed temporarily, and you can see the terminal block betwen the two ribs.

Yesterday was a ton of work aimed primarily at having a lot fewer little half-done tasks laying about adding to that feeling of frustration. First on the list is something that’s been bugging me for two months: the AHRS mount. I dragooned Shelley into helping me for a bit, first we did the dimpling for the relay deck hardware, then the rest of the dimpling for the AHRS mount. This thing has a LOT of rivets along the bottom. The dimpling’s done, but the rivets aren’t, and that was on my list to finish, but it got pushed in favor of actually finishing some other things that have been nagging at me for a while. Here’s the AHRS mount, nestled near the floor, creating a level spot for the SP2 and SP4 sensors:

In the pic, you can see the sensors fastened to standoffs on the mount platform, with DB9 connectors coming out of them. Originally, I had the ribbon cable supplied by MGL, but mounting the single connector with the ribbon cable was awkward and the longer ribbon cable I made (after a long-ass drive to the Valley) didn’t fire up both sensors, so I just made each one its own DB9 connector. The MGL-supplied ones had RCA audio connectors for data, which didn’t sit too well with me, so now I have proper crimped connections on both sensors. I still need to dress and secure the wire bundle a little bit, but it’s working pretty well.

This morning I had intended to finish that process, as well as do some other things in the back of the plane, like install the TNC terminal on the cable for the Garmin GPS antenna. Of course I screwed up the terminal pin, so I had to replace it, somehow. It was an amazing SoCal day, so I took the Buell, went to Fry’s and got my TNC and BNC connectors. funny thing though. RG58 connectors don’t work on RG400 cable. The center conductor is too thick to fit in the pin housing and the ferrule is too small to go over the insulation and leave enough room to get the connector body between the braid and the center insulator. Mouser to the rescue. Apparently the type needed are RG142/RG400 terminals. ACS sells these bad boys for $38 a pop, but Mouser has them for $7.95. I also got a bunch of BNC connectors for the backplate-side connections. The only thing is, you have to slog through Mouser’s online catalog, which blows chunks, at least until you light up the enhanced catalog, which is like an interactive version of their PDF catalog. That’s easy to figure out. I also took the opportunity to order a threaded CPC (circular plastic connector) for the pax stick disconnect.

This pic shows two DB9 connectors attached to the MGL Com Extender. These are the connectors for the Trio Gold Standard Autopilot servos.

I finished up the connectors and ran power, and guess what? The autopilot servo works. There’s a menu in the EFIS, where you select your AP mode, and which servo is connected to what port. Another menu is testing and diagnostics. I can report that the pitch servo definitely does what the test suite asks it to do. This is one of the reasons I didn’t get the AHRS mount riveted (plus Shelley was baking bread, and I can’t ask her to buck rivets when there’s bread in the works). This also meant I had to wire the AP panel switch as well, which I’d been putting off. It is now DONE!

I also got the backup instrument going, a MGL AV-2.

It has an artificial horizon, compass, and turn coordinator, so if the EFIS ever packs up, I have that to fall back on. It’s using the same sensors as the EFIS, but the rate of failure on the SP2/SP4 combo is so low as to be almost statistically impossible.

Remember when I said, regarding the stick wiring, “this is wrong?” This is why.

I put ring terminals on the pilot stick wires and attached them all to the terminal block, then tested them all with a multimeter just to make sure I had contact on all the switches. I’m glad I did. Every switch beeped except the thumb-operated flaps-up. The reason for this is that stupidly, I wired the flaps-up wire into the bundle with the grounds. I have no idea why, total brain fart. Maybe I thought the black/red wire was a ground of some kind for that switch. Fortunately, I saved all the excess wire from the bundle-thinning operation and was able to salvage the red-and-black wire that I’d cut off. I spliced it back in, and now I have redo the double-layer of shrinkwrap, put on new ring terminals, and reinstall.

But I feel pretty good about this week.. I think I can get the flaps and trim wired up, and be pretty much done with control wiring, assuming I can figure out how to make the start buttons on the stick work the starter.

Fun while it lasted.

May 11, 2011 / posted in Electrical, Panel / No Comments

2 hours.

Yay. Another week, another gout attack. And tonight, my EFIS decided to go funny on me. More on that later. Before my knee flared up again, I got the panel painted, in textured black Rustoleum, which looks very nice indeed. I’m rather pleased with how it came out. This is after I cut the holes for the MGL AH2 and the Falcon compass. I reinstalled the panel, added the new instruments and hooked the EFIS back up. It now does this weird thing where large horizontal bars show noise in the blue channel across the screen. Major, major suckage. I now have to de-ass the EFIS and take it back down to MGL in Torrance, where hopefully they can fix it. I hope it’s not something stupid like an aluminum chip on a board somewhere. I think it would just pack up and die if that were the case though.

Tonight, I ran the load wires from the panel to the left and right landing lights and the pitot heat. Why am I doing pitot heat again? Oh yeah. I want to fly IFR in this thing. There are still a million things to do, electrically speaking, but I did order my terminal blocks and audio jacks. While I was chairbound this weekend, I also stripped off the blue outer sheath on the Infinity grips and combined all the ground wires into one, which reduces the thickness of the stick wiring bundle considerably. This is a good thing. Now I don’t have to drill a vast 5/8″ hole in the stick to egress the wires out to where they’ll go to the terminal blocks. A big hole in the control stick may or may not be a bad idea. Van’s doesn’t recommend drilling the stick because it weakens the tubing, especially if the hole is near the pivot. But lots of guys have done it and they’ve not broken a control stick off yet.

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