Couple of Questions

[jiott]

Do I need to run coax cable from my PTT button on the top of my control stick (I bought the simple ones from Kitfox) down thru the stick and to my radio, or can I use the small unshielded wire like comes on the push-button? If I should use coax it seems like a quite large hole needs to drilled in the side if the stick to exit the wire. I have been reading here on the forum about people having interference with their headsets when they activate the PTT.
On my tailwheel leaf spring (the SS7 3 leaf) should I lubricate between the leaves before I final assemble it or leave it dry? The leaves will move relative to one another as the spring flexes and it seems like I heard that automotive leaf springs should be lubricated.
Jim

[Agfoxflyer]

I've built two airplanes and used unshielded wire for the PTT and have not had a problem. Can't help on the tail spring, used the grove aluminum spring.

[DanB]

Do I need to run coax cable from my PTT button on the top of my control stick (I bought the simple ones from Kitfox) down thru the stick and to my radio, or can I use the small unshielded wire like comes on the push-button? If I should use coax it seems like a quite large hole needs to drilled in the side if the stick to exit the wire. I have been reading here on the forum about people having interference with their headsets when they activate the PTT.
On my tailwheel leaf spring (the SS7 3 leaf) should I lubricate between the leaves before I final assemble it or leave it dry? The leaves will move relative to one another as the spring flexes and it seems like I heard that automotive leaf springs should be lubricated.
Jim

Jim,
Concerning the PTT wire...Use the small wires that probably came with your kit. This is a very small signal that activates (or turns on ) your transmitter when you push the button. The real work (amperage draw) takes place in the radio and travels to your antenna via what should be a coax cable. The noise that some encounter is sometimes hard to trace, but the usual culprits include ground loops in the system, as well as RF interference sometimes when a "fat or big hot" wire parallels radio / intercom wires. A great resource to learn more is here: http://www.aeroelectric.com/articles.html
I would not hesitate to purchase Bob's book that covers all things aviation electronics. Enjoy the read
Dan

[cap01]

lots of good info and diagrams in the aeroelectric book , well worth the money

[Av8r_Sed]

I ran a very small sheilded pair to my PTT switches (not coax). So far I've had zero electrical gremlins.

-- Paul S

[szicree]

++1 on Bob's book. It allowed me to confidently do all the electric on my RV and I learned a lot (most of which I've forgotten, so don't quiz me).

[jiott]

Do I need to run coax cable from my PTT button on the top of my control stick (I bought the simple ones from Kitfox) down thru the stick and to my radio, or can I use the small unshielded wire like comes on the push-button? If I should use coax it seems like a quite large hole needs to drilled in the side if the stick to exit the wire. I have been reading here on the forum about people having interference with their headsets when they activate the PTT.
On my tailwheel leaf spring (the SS7 3 leaf) should I lubricate between the leaves before I final assemble it or leave it dry? The leaves will move relative to one another as the spring flexes and it seems like I heard that automotive leaf springs should be lubricated.
Jim

I never did get any replies to my question #2.

[DanB]

I never did get any replies to my question #2.

I hate it when that happens! Sorry, I got the little wheel in the front right now.

[cainbird]

Jim,
I have never lubed my tail springs. I feel it would just envite dirt and sand to stick between the leaf springs. Of course this is just my intuition and is not backed by any scientific data to prove it!

Cain B

[HighWing]

I have seen auto leaf springs with what looked like a thin sheet of Teflon? between them. From that I supposed that a lube would be a good idea. I tried the teflon thing - actually using Delrin I machined a thin disk with a bump on it that would fit into a detent I made on the end of one the top leaf. It worked fine until the tailwheel reversed during pushing backward then popped out. I like the lube idea, but suspect it would be a one time process, then over the years the lube would disappear. I guess right now I would go dry and maybe using some of the flaperon spray lube from time to time.
Lowell

[jiott]

Yea, maybe that light LPV-1 penetrating spray lube occassionaly. It dries to a dry film so should not attract dirt.

Jim