APRS mounting other than wingtips

ArVeeNiner · #1 11-15-2011, 09:31 PM

OK, I screwed the pooch! In my haste to mount my wings a couple of weeks ago, I forgot to run my APRS power and GPS wires through the wing conduit. I also forgot to run and leave a string in the wing. So my only option is to pull my nav light wire through with a couple of strings attached. If for some reason the strings let go halfway through, I'm really in a jam. Of course, I've run the APRS wires towards the left side of the fuselage which means the left wing is what I was shooting for. That is jam packed with wires and two lines from the pitot.

After a feeble attempt tonight, I decided I better go to plan B. My question is, what exactly IS plan B?

Yea, I guess I can run an external antenna but I'm not excited about that. If that was the best option, what antenna do I use?

Plan C would be to mount the unit and its antenna inside the cockpit. I have my ELT antenna mounted inside behind the pilot. Has anybody had success with mounting the APRS internally near the Plexi?

Any other ideas?

gnuse · #2 11-15-2011, 09:38 PM

I powered my APRS with GPS unit off the nav lights. I didn't have to pull any wires.

jwyatt · #3 11-15-2011, 11:23 PM

I mounted my APRS box (MicroTrak RTG) right below the ELT on Vans' mounting bracket. If you're using a similar transmitter, it's small enough that it could be mounted to a rib or bulkhead back there, as well, if you want it on the left.

Can't help much with the internal antenna; I bought one of the Antenex "Phantom elite" antennas that someone else on this site tried out. Mounted it centered in the bottom skin, underneath the baggage floor, with an NMO mount. The cable exits the mount parallel to the skin at a right angle, so it can easily be tied up and not interfere with the pushrod that runs through there.

Since my box is behind the baggage bulkhead, I modified it a bit to bring the LED indicator (which tells you if it's receiving a valid GPS signal, and also when it sends a packet) out to a connector, and mounted a remote LED at the side of the bulkhead. Along with that, a normalling minijack to allow for easy connection of the laptop for programming changes, without having to pull the baggage wall.

Vlad · #4 11-16-2011, 04:19 AM

Quote:

Originally Posted by ArVeeNiner

Any other ideas?

If you want internal rudder bottom fairing might work.

VHS · #5 11-16-2011, 06:38 PM

Quote:

Originally Posted by gnuse

I powered my APRS with GPS unit off the nav lights. I didn't have to pull any wires.

How did that Antenex antenna work out for you?

Allen
VHS

gnuse · #6 11-16-2011, 06:43 PM

Quote:

Originally Posted by VHS

How did that Antenex antenna work out for you?

Allen
VHS

The antenna worked very well. I did use one of Pete's in the wingtip however to support Prom, I believe.

ArVeeNiner · #7 11-17-2011, 08:35 AM

Thanks for the tips. I never thought of just hooking it to the nav light. That's a great idea! This would probably would be best if you had LED nav lights, which I don't. With regular bulbs from the last century, I would imagine that you'd have to change them often due to the fact that nav lights would be on at all times.

I think I'm still going to pursue Plan A. I need to find a 12' long wire "coat hanger". There is a steel place near my work that might have something like this. There might also be something at the local hardware store as well but I haven't had time to look yet. I'm thinking that I can use one of those as a giant needle with some string (the thread) taped to the pointy end. I can then feed it in the conduit from the wingtip in towards the fuselage. I'm also going to look at routing through the right wing because there is less stuff stuffed into the conduit on that side.

Thanks again!

FlyingArcher · #8 11-17-2011, 09:23 AM

You might also try to run a nylon wire puller through your conduit in order to pass additional wires through it. This kind of device can be found in any Home Depot or such kind of store and IS useful. Ask me how I know

ArVeeNiner · #9 11-17-2011, 10:33 AM

I'll look into a wire puller. I just had a though. My daughter's soccer coach is an electrician. I bet he has something I could borrow.

Thanks.

Don · #10 11-17-2011, 10:35 AM

If you have conduit in place, take a piece of string longer than the conduit, tie a cotton ball to one end and tie the other end to something relatively immobile near one end of the conduit. Stick the cotton ball in the conduit. Now take your shop vac to the other end of the conduit and turn it on. In about a half second or so you'll have a string all the way through your conduit. Now pull the wire through for you APRS along with another piece of string (for future use). If you didn't use conduit, well you're right about the pooch.