I may be overthinking it just a tad, too.  I just cant seem to focus my
skills in one area, and thats my real problem.  I like all of it.

Just like in ex motors, you solve a problem, but affect other things you
may be unaware your changing. Engineering always has its moving targets.

Thanks, i will keep it simple and run twisted pairs. its what i have too.

I have decided to go ahead and solder contact pin to the wires, it will
just be cleaner, i am always afraid of the stray strand crossing terminals
on me.
http://www.alliedelec.com/search/productdetail.aspx?SKU=70083101
http://www.alliedelec.com/search/productdetail.aspx?SKU=70099258#tab=overview
I can use some heat shrink and have a nice taylored and clean harness.

Clay
On Wed, Mar 27, 2013 at 2:00 PM, w9ya <[email protected]> wrote:

> Perhaps I should explain this a bit further....
>
> R.F. energy travels along the surface of conductors. Shields have two
> surfaces where R.F. energy can travel whereas the simple conductor has
> only one such surface. The "second" surface of shields not properly
> accounted for is where "problems" often reside.
>
> There are whole chapters of engineering text books devoted to this
> subject and this is merely a short and simple set of email ramblings,
> but rest assured that shielding can be a real pain in your rear for
> the reason touched upon in these emails. And the complex impedance
> presented at any specific point along the shield and the calculations
> involved to properly consider these values are not so simple a matter
> as the other, un-shielded, scenario where one merely shunts r.f.
> energy at the connection points of a simple un-shielded twisted pair.
>
> Very best regards;
>
> - Bob Finch
>
>  On Wed, Mar 27, 2013 at 10:32 AM, w9ya <[email protected]> wrote:
> > I'd have to look at the circuit in more detail to be assured of this
> > v/v the altus metrum fligh units, but generally the need for shielding
> > in the wiring looms is over-rated and further the shielding can act
> > like a parasitic antenna where twisted (specifically by pairs) wiring
> > would not otherwise be a problem.
> >
> > Very best regards;
> >
> > - Bob Finch
> >
> > On Wed, Mar 27, 2013 at 10:28 AM, w9ya <[email protected]> wrote:
> >> Um....I use the following;
> >>
> >> 1 - Properly routed and supported *stranded* wiring. i.e. NO
> >> unsupported flexing of the wiring loom.
> >>
> >> 2 - Tinned (with solder of course) wiring is specifically indicated.
> >> It will not release from under the screw terminal when the terminal is
> >> properly tightened and supported.
> >>
> >> 3 - Double check the connections before each flight; by making sure
> >> the wiring and screw are snug AND that the wiring is still routed and
> >> supporteed correctly.
> >>
> >> YMMV of course but I preclude intermittent continuity issues resulting
> >> from the lack of a gas tight ferrule connection.
> >>
> >> Very best regards;
> >>
> >> - Bob Finch
> >>
> >>
> >>
> >> On Wed, Mar 27, 2013 at 8:16 AM, Thomas Müller
> >> <[email protected]> wrote:
> >>> If you like to attached stranded wire to screw terminals you should
> crimp
> >>> the ends in a ferrule. Tin soldering is not a good idea since the thin
> is
> >>> pretty soft and flowable which might lose the connection.
> >>>
> >>>
> >>>
> >>> Thomas
> >>>
> >>>
> >>>
> >>> Von: [email protected]
> >>> [mailto:[email protected]] Im Auftrag von Clay & Carly
> >>> Dunsworth
> >>> Gesendet: Mittwoch, 27. März 2013 14:59
> >>> An: Altus Metrum
> >>> Betreff: Re: [altusmetrum] wires
> >>>
> >>>
> >>>
> >>> I have always steered away from the solid core.  Most of the time where
> >>> space isnt critical ive used machine tool wire, but doesnt work with
> the
> >>> "smallness" of the Altus Metrum products.(16ga).  I bought some
> smaller 26ga
> >>> stranded, becuase another altimeter i have, the MFG suggest 26ga
> stranded as
> >>> the "smallest" wire that would be safe.  this was after I discovered
> blue
> >>> color on the copper of the ematch leads. (now i suspect chemical
> reaction of
> >>> the bare copper, oily fingers, and BP residue.) Oddly its almost too
> big for
> >>> the TM i have.
> >>>
> >>>
> >>>
> >>> I have never tinned the ends of my wires, but the belkin cable i cut
> up the
> >>> other day suprised me that the wires were stranded copper, and seemed
> >>> suitable for this. I always envisioned they were like old telephone
> cable
> >>> with that fiberstuff, that would be unsuitable.  Maybe with this small
> of a
> >>> gage i should solder tin the ends for added reliablity?
> >>> I have litterally hundreds of feet of the stuff, and would be a
> "freebe" for
> >>> the rest of my av-building life.
> >>>
> >>>
> >>>
> >>> Clay
> >>>
> >>> I guess thats why we test!
> >>>
> >>> On Tue, Mar 26, 2013 at 10:41 PM, Michael Stephens <
> [email protected]>
> >>> wrote:
> >>>
> >>> My only worry would be that solid core wire doesn't like vibration
> very much
> >>> but stranded wire doesn't do well in screw terminals. I would think it
> could
> >>> definitely handle the voltage, especially since its such low duty
> cycle.
> >>>
> >>> On Mar 26, 2013 8:16 PM, "Clay & Carly Dunsworth" <
> [email protected]>
> >>> wrote:
> >>>
> >>> Anyone use cat5e cable for thier avionics bay?
> >>>
> >>> Making a small launcher for the kids, i noticed the 4 twisted pair i
> >>> have would be a good match for my bay?
> >>>
> >>> Its good for things like telephones and data signal, but what about
> >>> ematch voltage?
> >>> thinking the sheething and twisted pair may be good at RF shielding?
> >>> Clay
> >>>
> >>> _______________________________________________
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> >>>
> >>>
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> >>>
> >>>
> >>>
> >>>
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