Source of RJ-45 cables for connecting FLARM, K6 Mux, etc.

I'm curious about the type of RJ-45 cable needed to connect
various .icg-compliant glider instruments, such as a PowerFLARM, K6
Mux, PNA, etc..

First, are the RJ-45 cables (assuming no special connectors or
requirements, just power and data) straight through or crossed?

Second, can regular Cat 6 Ethernet cables be used, or do they have to
be shielded?

Some of the prices I've seen for what appear to be straight RJ-45
patch cables at glider equipment dealers are a bit breathtaking
compared to computer cable stores so I'm wondering if I've missed
something!

Any advice would be appreciated.

Kirk
66

On Dec 9, 4:25*pm, "kirk.stant" wrote:
I'm curious about the type of RJ-45 cable needed to connect
various .icg-compliant glider instruments, such as a PowerFLARM, K6
Mux, PNA, etc..

First, are the RJ-45 cables (assuming no special connectors or
requirements, just power and data) straight through or crossed?

Second, can regular Cat 6 Ethernet cables be used, or do they have to
be shielded?

Some of the prices I've seen for what appear to be straight RJ-45
patch cables at glider equipment dealers are a bit breathtaking
compared to computer cable stores so I'm wondering if I've missed
something!

Any advice would be appreciated.

Kirk
66

Kirk, here is some info I shared on the xcsoar mailing list for
connecting 302 to Dell Streak via K6Bt. You may find some answers
the

Parts:

Outerbox impact cover (optional) http://www.amazon.com/OtterBox-Dell-.../dp/B004MG3OTW
($10)
Slipgrip Mount (few options to choose from) -
http://www.slipgripcarmounts.com/Usi...e_c_21746.html ($40)
K6BT - http://www.cumulus-soaring.com/k6.htm ($175)
DB9 Male to RJ45 Modular Adapter - http://www.amazon.com/gp/product/B0016RO20U
($4)
Extra Dell Streak cable - http://www.amazon.com/gp/product/B005AL36SW
($9 incl shipping)
2 x Network Cable - http://www.amazon.com/gp/product/B000V0ET92 ($2
each)
Instructions:
1 - Insert the RJ45 pins into the DB9 modular adapter according to the
following:
Red to pin2
Black to pin3
blue to pin5
brown to pin6
white to pin8
(the rest can go anywhere)
2 - Connect a netwrok cable between the K6Bt and the above DB9
adapter. This will provide power and communication to the K6Bt.
3 - Velcro the K6Bt to the 302, and follow the instructions that came
with the K6Bt to pair with the Streak, then select the K6Bt device in
XCSoar and the CAI 302 driver.
4 - The above should be sufficient for up to 5 hours flight. If you
need longer than that, follow the instructions below to connect the 5v
to charge the Streak.
5 - Cut the Streak Cable and the other network cable.
6 - Carefully solder pin 1 from network cable (White/orange) to the
Streak cable black wire (GND) , and pin 8 from the network cable
(brown) to the Streak red wire (+5).
7 - Connect this cable between the other K6Bt connector and the Streak
to charge the Streak in flight.

Hope this helps,

Ramy

On 10 Dez., 01:25, "kirk.stant" wrote:
I'm curious about the type of RJ-45 cable needed to connect
various .icg-compliant glider instruments, such as a PowerFLARM, K6
Mux, PNA, etc..

First, are the RJ-45 cables (assuming no special connectors or
requirements, just power and data) straight through or crossed?

Second, can regular Cat 6 Ethernet cables be used, or do they have to
be shielded?

Some of the prices I've seen for what appear to be straight RJ-45
patch cables at glider equipment dealers are a bit breathtaking
compared to computer cable stores so I'm wondering if I've missed
something!

Any advice would be appreciated.

Kirk
66

You can basically use any RJ-45 patch kabel except for the crossed
ones. As far as my experience goes it is not necessary to get a
shielded kabel (CAT 5 and 6).

The problem with using "computer" cables is that they would be much
too long for most soaring applications - not to mention that putting
the connectors on with the wires in the right order is a pain in the @#
$%.

Making your own flat cables is simple and inexpensive - not to mention
that you can make it exactly the length that you need.

1) "silver satin" 8 conductor flat cable
http://www.amazon.com/IEC-Gauge-Cond...838509&sr=8-17
2) 8 conductor RJ-45 connector
http://www.radioshack.com/product/in...ductId=2292431
3) RJ-45 Crimping/stripping tool
http://www.radioshack.com/product/in...ductId=2255112

The sources I show above are ones that are likely to be viewable in
the months ahead. But you can find all of this on eBay for cheap.

NOTE: Every soaring cable I have seen is "straight through" - that is,
if you hold the two ends next to one another the colored wires are in
the same order. YMMV.

- John

On Dec 13, 11:07*pm, JohnDeRosa wrote:
The problem with using "computer" cables is that they would be much
too long for most soaring applications - not to mention that putting
the connectors on with the wires in the right order is a pain in the @#
$%.

Making your own flat cables is simple and inexpensive - not to mention
that you can make it exactly the length that you need.

1) "silver satin" 8 conductor flat cablehttp://www.amazon.com/IEC-Gauge-Conductor-Silver-Satin/dp/B003U42NPS/...
2) 8 conductor RJ-45 connectorhttp://www.radioshack.com/product/index.jsp?productId=2292431
3) RJ-45 Crimping/stripping toolhttp://www.radioshack.com/product/index.jsp?productId=2255112

The sources I show above are ones that are likely to be viewable in
the months ahead. *But you can find all of this on eBay for cheap.

NOTE: Every soaring cable I have seen is "straight through" - that is,
if you hold the two ends next to one another the colored wires are in
the same order. YMMV.

- John

One last question - and I'm showing my complete ignorance here - are
all the pins on a "standard" RJ45 cable hot? And is there any problem
sending 12v across them to power a K6 Mux and a PowerFLARM, for
example?

Kirk
66

On Dec 15, 7:39*pm, "kirk.stant" wrote:
On Dec 13, 11:07*pm, JohnDeRosa wrote:

NOTE: Every soaring cable I have seen is "straight through" - that is,
if you hold the two ends next to one another the colored wires are in
the same order. YMMV.

- John

One last question - and I'm showing my complete ignorance here - are
all the pins on a "standard" RJ45 cable hot? And is there any problem
sending 12v across them to power a K6 Mux and a PowerFLARM, for
example?

Actually you had two questions

1) Hot usually indicates that they have a voltage on them that isn't
zero. Is that what you mean? Or do you just mean if all the pins are
connected one end to the other? The answer to the last question is
yes for a flat cable and almost always yes for a computer networking
cable.

2) Sending 12v across this cable isn't really what you need to
understand. The question is how much current you need to run across
the wires in the cable. Do you know? (hint: read the equipment
specs) Current carrying capacity depends on the gauge of the wire -
and the larger the gauge the more current carrying capacity the wire
can handle. Too much current for the gauge and the wire gets hot and
the insulation melts - not good. These flat telephone cables are in
all probability 26ga which is about as small as you are likely to
encounter short of the wiring inside a pair of ear buds. There is a
chart which explains everything in FAA AC 43.12-1B, Chapter 11,
Section 5, Page 11-30 and 31 - but it only goes down to 24ga (bigger
number = smaller gauge). Here is the link;

http://rgl.faa.gov/REGULATORY_AND_GUIDANCE_LIBRARY/RGADVISORYCIRCULAR.NSF/0/99c827db9baac81b86256b4500596c4e/$FILE/Chapter%2011.pdf

If I read the chart correctly 24ga is good to 5amps at 14V for 8 ft
with a 1Vdc drop. Someone check my math. But would I run power
through itty-bitty 26ga wire, let alone several amps? Nope. Signals
yes, power no. Stick with tefzel. My $0.02.

- John