A couple of general questions

[Carlos Rey-Moreno]

Good evening!

I have a couple of questions regarding installing Mesh Potatoes and
designing a mesh network with them, and I hope somebody from the list
can help me:
- Is there any maximum length for using Power over the Telephone Line?
- If the rate the Mesh Potatoes are working is set to auto, how is it
choosen? They take into consideration every signal above the minimum
sensitivity that each node in the network receive from all the others
and so it's choosen the minimum modulation that could be used among all
the nodes in the network? or it could be limited as for having less of a
mesh but with using higher rates on the active links? or it is just
better to use a fix modulation?

Thank you very much in advance

Carlos

[Sjur Eivind Usken]

> I have a couple of questions regarding installing Mesh Potatoes and designing a mesh network with them, and I hope somebody from the list can help me:
> - Is there any maximum length for using Power over the Telephone Line?

You need 12 volt minimum on the mesh potato. Thsi should not drop below 12 volt when you power it up as well. It will boot on lower, but the phone port will get trouble powering the handset. The mesh potato handles up to 50-60 volt input, so for a longer run, have higher voltage. It also depends on how big diameter the wires are.

Sjur

[elektra]

Hi -

> You need 12 volt minimum on the mesh potato. Thsi should not drop below 12 volt when you power it up as well. It will boot on lower, but the phone port will get trouble powering the handset. The mesh potato handles up to 50-60 volt input, so for a longer run, have higher voltage. It also depends on how big diameter the wires are.

at ~42 Volt the overvoltage protection circuitry of the MP will kick in. The current MP production devices are shipped with 24 Volt power supplies. If you use a 24 Volt power supply and a telephone cable with 6 wires the available length should be by far longer than required in any case (in excess of 50 meters).

Here an example calculation for 4 wire telephone cable:

Assuming the copper cross section is 0.08mm² per wire and you have 50 meters cable, you have 2 wires for power and 2 wires for the phone connection.

0.01786 Ohm/meter for 1mm² cross section is the specific resistance of copper. This results in 0,23 Ohm/meter of wire (0.01786 / 0.08). Since we have one wire going to the MP and one coming back - in order to close the circuit - that is 100 meter total wire length. Resulting in 23 Ohm wire resistance (0.23 x 100). That is a lot ;) However, taking into account that the MP draws around 0.2 Ampere at 18 Volt, the voltage drop at 0.2 Ampere would be 4,6 Volt for that current (23 Ohm x 0.2 Ampere)

=> With a 24 Volt power supply you will still have ~ 19 Volt at the MP.

Cheers,
Elektra

[elektra]

Hi -

> - If the rate the Mesh Potatoes are working is set to auto, how is it
> choosen? They take into consideration every signal above the minimum
> sensitivity that each node in the network receive from all the others
> and so it's choosen the minimum modulation that could be used among all
> the nodes in the network? or it could be limited as for having less of a
> mesh but with using higher rates on the active links? or it is just
> better to use a fix modulation?

the Madwifi wireless driver uses a sophisticated rate contol algorithm called Ministrel. The transmission rate is chosen individually for each neighbor which is in range. Ministrel uses the data rate with the best compromise of data rate and retransmissions. You can monitor this data with the wlanconfig command line utility.

root@Mesh-Potato:~# wlanconfig ath0 list
ADDR AID CHAN RATE RSSI DBM IDLE TXSEQ TXFRAG RXSEQ RXFRAG CAPS ACAPS ERP STATE MODE
00:09:45:57:71:14 0 10 36M 0 -95 0 8 2 1839 0 0 1 Normal
00:23:cd:b8:75:c6 0 10 36M 21 -74 0 7 4 1354 0 0 1 Normal
00:23:cd:b8:32:d7 0 10 36M 25 -70 0 0 0 970 0 0 1 Normal
00:1a:70:4f:00:39 0 10 36M 24 -71 0 0 0 736 0 0 1 Normal

Note that in order to measure the data rate there must be unicast traffic. If the mesh is idle the driver reports 36Mbit as default.

There are simple rate control algorithms out there, that simply reduce the transmission rate in case of packet loss. Ministrel also tries higher rates, because packet loss doesn't always mean lack of signal to noise ratio, but can also be caused by collisions. Transmissions with faster data rate are less likely to collide in the media.

Cheers,
Elektra

[Carlos Rey-Moreno]

Wow! Thank you very much for the explanation! couldn't be more detailed, :-)

One last question, would you recommend the use of 4 wires or 6 wires telephone cable? What difference that is make?

Best,

Carlos

2012/5/16 elektra <onel...@gmx.net>

--
You received this message because you are subscribed to the Google Groups "village-telco-dev" group.
To post to this group, send email to village-...@googlegroups.com.
To unsubscribe from this group, send email to village-telco-...@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/village-telco-dev?hl=en.

[Carlos Rey-Moreno]

Thanks a lot again, Elektra! I though they had to use the same rate in the whole neighborhood as for the Mesh Potato to expect packets carrying info modulated on a certain fashion, but I guess that info is codified in the preamble, so they can use different rates with different neighbors.

So, then it is stable? I mean, is it better to leave it configured as auto? or to be conservative and use a slower data rate that will fit on the worst case scenario for all?

Best,

carlos

2012/5/16 elektra <onel...@gmx.net>

Cheers,
Elektra

[elektra]

Hi -

> One last question, would you recommend the use of 4 wires or 6 wires
> telephone cable? What difference that is make?

6 wires is recommended, but it is probably harder to get.

Cheers,
Elektra

[elektra]

Hi -

> Thanks a lot again, Elektra! I though they had to use the same rate in the
> whole neighborhood as for the Mesh Potato to expect packets carrying info
> modulated on a certain fashion, but I guess that info is codified in the
> preamble, so they can use different rates with different neighbors.
>
> So, then it is stable? I mean, is it better to leave it configured as auto?
> or to be conservative and use a slower data rate that will fit on the worst
> case scenario for all?

Ministel is the current state of the art in rate control AFAIK and it is fully implemented and tested for ad-hoc mode in the driver. What more can one possibly ask for? ;) Using a manual setting is like driving a car without releasing the hand brake...

Cheers,
Elektra

[Song, Stephen]

If you really need 6 wires, which with the 24V power supplies less likely, you might be better off using CAT5 cable and clipping one of the pairs off.  This works pretty well and you can buy UV rated CAT5 for truly rugged outdoor life.

-Steve

 

Cheers,
Elektra

--
You received this message because you are subscribed to the Google Groups "village-telco-dev" group.
To post to this group, send email to village-...@googlegroups.com.
To unsubscribe from this group, send email to village-telco-...@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/village-telco-dev?hl=en.

--
Steve Song
http://manypossibilities.net
http://villagetelco.org

[Dave Duchesneau]

> 6 wires is recommended, but it is probably harder to get.

> If you really need 6 wires, which with the 24V power supplies less likely,

> you might be better off using CAT5 cable and clipping one of the pairs off.

 

But 8 is better than 6.  Instead of clipping off one of the pairs, I would use it in parallel to double up the current capability of the cable, since you’re paying for the extra conductors anyway.  This has a couple of key benefits:

 

1. Depending on the grade of 6-wire cable you would have chosen, the 8-wire CAT5 cable may be a lighter gauge, and thus have less current-carrying capacity.  If you use the same number of conductors, each conductor of an 8-wire cable would thus have a higher resistance than its 6-wire counterpart, resulting in a higher voltage-drop.  Using the extra conductors in parallel would compensate for this.
   
   
2. Even if the individual conductors in the 6-wire cable and the 8-wire CAT5 were the same gauge, using the extra conductors in parallel would increase the current-carrying capacity and reduce the power-circuit resistance, thus lowering the voltage drop, which is a very good thing if electricity is expensive, or if you need to operate on battery power.  
   
   For example, if the voltage drop from a 24V source supplying 0.2 Amperes across a set of 23 Ohm conductors is 4.6 volts (using Elektra’s earlier example values for continuity), yielding 19.4V (~19V) at the MP, then the voltage drop in the conductors corresponds to a loss of almost 1 watt (4.6 Volts x 0.2 Amperes = 0.92 Watts).  Since the MP itself draws ~0.2 Amps at 18V, or about 3.6 Watts, this means that the power-supplying conductors are using more than a quarter of the power that the MP itself consumes (100 x 0.92 Watts / 3.6 Watts = 25.5%).  However, the total power consumed is additive, so the MP consumes 3.6 watts and the wire consumes another 0.92 watts, for a total of 4.52 watts.  Thus, the power loss due to voltage drop in the wire accounts for more than 20% of the total power needed to operate the MP (0.92 watts / 4.52 watts = 20.3%).  If you double the conductors, then you halve the power loss due to voltage drop.  In an 8-wire CAT5 pair, the extra conductors are already there, so why not use them?

 

Note that in both Elektra’s example and in mine, the use of 23 Ohms as the wire resistance (for DC voltage) is very specific to the length and gauge of wire used.  Longer wires have higher resistance (and thus higher voltage-drop and power loss).  Fatter conductors (lower gauge) have lower resistance (and thus lower voltage-drop and power loss).  That’s why you have to use heavier gauge (lower gauge number) wires (or more of them) for longer electrical runs of any kind.

 

Good luck!

 

Dave Duchesneau

d...@crisis-force.org

 

 

---

[Carlos Rey-Moreno]

"Message received" :-)

Thanks

Carlos

[Carlos Rey-Moreno]

@Steve, Thanks for the CAT5 recommendation we'll consider it.

@Dave, is it a 8 pin RJ11 as for trying what you are suggesting?

Best,

Carlos

2012/5/17 Dave Duchesneau <d...@crisis-force.org>

[Dave Duchesneau]

Ø      @Dave, is it a 8 pin RJ11 as for trying what you are suggesting?

 

No, CAT5 cable would typically be wired common RJ45 (RJ-45) connectors, which have 8 conductors.  It looks a lot like an RJ45, but is somewhat larger.

 

Dave

 

---

[Carlos Rey-Moreno]

Ok, then we can not use your idea for PoTL, since the connectors need to be RJ11 and the maximum of pins they have is 6, thanks anyway.

Best,

Carlos

[Sjur Eivind Usken]

Seven though the cat5 cable has 8 wires, it is just to not use the last pair.

It is no problem using a cat5 cable with rj11 plugs, but you just use 6 of the wires....

Vennlig hilsen

Sjur Eivind Usken

[Wayne Abroue]

On Wed, May 23, 2012 at 9:18 AM, Sjur Eivind Usken <sj...@usken.no> wrote:
> Seven though the cat5 cable has 8 wires, it is just to not use the last
> pair.
>
> It is no problem using a cat5 cable with rj11 plugs, but you just use 6 of
> the wires....
>
>
> Vennlig hilsen
>
> Sjur Eivind Usken
>

A option also is use 3 or 4 pair coms cable, I have found it about
half the price if comparing to Cat5.
Your local electrical supply should carry. You could even find a
larger guage in this type.

Wayne

[Carlos Rey-Moreno]

On 23/05/2012 09:28, Wayne Abroue wrote:
>> It is no problem using a cat5 cable with rj11 plugs, but you just use 6 of
>> the wires....

Sure! I was answering @Dave

> A option also is use 3 or 4 pair coms cable, I have found it about
> half the price if comparing to Cat5.
> Your local electrical supply should carry. You could even find a
> larger guage in this type.

Thanks Wayne, we'll consider it too.
> Wayne
>

[Carlos Rey-Moreno]

Finally we got shielded 8-wires Cat5, and I was wondering what happen if there is short circuit in the cable, or in the router. Will the PoTL adapter work as a fuse, or will it go all the way to the regulator burning both the cable and the PoTL?

By the way, sorry @Dave I think I got you recommendation wrong. According to http://wiki.villagetelco.org/images/3/39/MP01_Hardware_Description_2010-05-02.pdf the ping 1 & 2 of the connector should carry 12V, 3 & 4 the Phone (ring & tip) and 5 & 6 0 Vdc input (MP01 Gnd). Your recommendation was using the two wires that we are not using lets call them 7 & 8 by clipping them together to one of the existing ping of the RJ25 connector? In that case would you recommend clipping 1 & 7 and 5 & 8?

cheers,

Carlos

2012/5/23 Carlos Rey-Moreno <cr...@ehas.org>

[Dave Duchesneau]

Hi Carlos,

 

Ø      By the way, sorry @Dave I think I got you recommendation wrong.

Ø       According to http://wiki.villagetelco.org/images/3/39/MP01_Hardware_Description_2010-05-02.pdf

Ø       the ping 1 & 2 of the connector should carry 12V, 3 & 4 the Phone (ring & tip) and 5 & 6

Ø       0 Vdc input (MP01 Gnd). Your recommendation was using the two wires that we are not using,

Ø       lets call them 7 & 8 by clipping them together to one of the existing ping of the RJ25 connector?

Ø       In that case would you recommend clipping 1 & 7 and 5 & 8?

 

 

I’m not sure I understand your question, but I’ll take a run at it.  My verbosity is intended to improve the likelihood that you’ll get what you need without having to go back & forth.  My original recommendation was simply oriented toward splitting any unused conductors (i.e., those not use for signaling) into power and ground, and merging all the power wires into a higher capacity, and doing the same for the ground.  The MP01 already merges 2 pairs this way, with pins 1 & 2 merged to carry 12V, and pins 5 & 6 merged to carry ground.  If you had more pins, you could merge more conductors, but you don’t, and so you can’t.

 

First, since 6 of the 8 CAT5 wires are accounted for in the MP01 H/W description, there is only 1 pair (2 wires) remaining).  To keep it simple, since pins 1-6 are spoken for, 7 & 8 seem like the obvious candidates to leave out (clip).  However, the pins are numbered on the connector, not the cable, which is colored-code according to pairs of wires.

 

In the attached image named “RJ45 Pinout (Zytrax.com).jpg” you will note that there are two different wiring standards that are commonly used with CAT5 and RJ45 connectors.  Since you are using CAT5, but *not* RJ45, you don’t have to worry about splitting the green pair (or any pairs), for example, as shown in the image named “RJ45 Plug with Cable (Nullmodem.com).jpg”.  

 

What is most important here is that you think of the CAT5 cable as having four PAIRS of conductors.  This is especially true for the telephone (ring & tip) conductors.  You should keep them as a pair, because the wires in the pair are twisted (hence, “twisted pair) in such a way as to be essentially orthogonal to each other (and to the other pairs), so as to reduce noise/crosstalk.

 

In your case, all the other pairs are available to carry power and ground.  Although it would be no big deal to use all three remaining pairs for power and ground if you attaching to a socket, it’s quite a different story with an RJ25 plug.  As far as I know, an RJ25 plug (which is like an RJ11 that can accommodate three pairs) can accommodate ONLY three pairs or less.  In your non-standard application, it doesn’t really matter WHICH three of the four pairs in a CAT5 cable, as long as the other end is wired compatibly. 

 

In the image named “RJ11, RJ14, RJ25 pinout with CAT5 colors (Neutrino.phys.ksu.edu).jpg”, you can see that all the pairs have been split up except for the center pair.  This is because each pair is carrying a signal (presumably voice, like on a multi-line telephone), and this pin-out ensures that each pair carries mating Tx/Rx signals for one phone line.  Note that the brown pair is the one omitted from this picture, which would mean it got clipped.  In your case, you only have one signal pair, so I would probably not split up the pairs used for power & ground.  It’s hard enough to crimp this type of plug without complicating things by having to split wire pairs.

 

Personally, I would choose three consecutive pairs that simplify the crimping operation, and clip off the fourth pair (since there’s no way to connect it to the RJ25 plug).  Make sure that the center pair is the one for voice.  That leaves a full pair dedicated to 12V, and another pair dedicated to GROUND, which simplifies construction by NOT splitting the pairs up as shown on the color-coded connectors.

 

To reiterate, in your non-standard application, the most important things are to:

1. Use a full pair for the center pins (3 & 4 on the RJ25) that carry voice, and
2. Wire both ends of cable in a compatible way.

 

Also, I would check the cable for continuity end-to-end, and ensure there are no shorts between 12V & ground, 12V & either voice conductor, ground & either voice conductor, or between voice conductors. 

 

I haven’t seen any discussion about whether you’re using solid or stranded CAT5 cable.  Solid is much easier to crimp correctly, but it is also more brittle and prone to fatigue, which is why CAT5 patch cables are always fabricated from stranded cable.

 

It would be advisable to make a wiring diagram of your cable, use it when you build the cable, and then save it permanently (I’d probably keep a copy handy, near one end).

 

It would be nice if someone else would jump in to confirm or deny my assertions here, especially if I’ve left out anything important.

 

Dave Duchesneau

d...@crisis-force.org

 

 

---

From: Carlos Rey-Moreno [mailto:cr...@ehas.org]
Sent: Thursday, May 24, 2012 10:06 AM
To: village-...@googlegroups.com
Cc: d...@crisis-force.org
Subject: Re: [vt-dev] A couple of general questions

 

Finally we got shielded 8-wires Cat5, and I was wondering what happen if there is short circuit in the cable, or in the router. Will the PoTL adapter work as a fuse, or will it go all the way to the regulator burning both the cable and the PoTL?

[Song, Stephen]

Confirmed Dave.

The jack you need for six pins in a telephone port is an RJ-12 or RJ25
jack (they are the same). They are not as easy to find as RJ-11 jacks
(Mantech is a great source in South Africa) and that is part of the
motivation to switch to a 24V PSU so that 4-wires would work in most
cases.

For using CAT5 with an RJ12 , I have a simple rubric. Keep the
primary/secondary colours i.e. clip the brown pair. Wire the pairs
alphabetically according to colour. Blue pair, Green pair, Orange
pair. Not terribly scientific but easy to remember.

Cheers... Steve

[Carlos Rey-Moreno]

Thanks Dave and Steve for the clarification, I just got confused by a
previous email from Dave regarding the use of the 8 wires.

Best,

Carlos

On 05/25/2012 09:38 AM, Song, Stephen wrote:
> Confirmed Dave.
>
> The jack you need for six pins in a telephone port is an RJ-12 or RJ25
> jack (they are the same). They are not as easy to find as RJ-11 jacks
> (Mantech is a great source in South Africa) and that is part of the
> motivation to switch to a 24V PSU so that 4-wires would work in most
> cases.
>
> For using CAT5 with an RJ12 , I have a simple rubric. Keep the
> primary/secondary colours i.e. clip the brown pair. Wire the pairs
> alphabetically according to colour. Blue pair, Green pair, Orange
> pair. Not terribly scientific but easy to remember.
>
> Cheers... Steve
>
> On 25 May 2012 00:17, Dave Duchesneau<d...@crisis-force.org> wrote:
>> Hi Carlos,
>>
>>
>>

>> � By the way, sorry @Dave I think I got you recommendation wrong.
>>
>> � According to
>> http://wiki.villagetelco.org/images/3/39/MP01_Hardware_Description_2010-05-02.pdf
>>
>> � the ping 1& 2 of the connector should carry 12V, 3& 4 the Phone

>> (ring& tip) and 5& 6
>>

>> � 0 Vdc input (MP01 Gnd). Your recommendation was using the two wires

>> that we are not using,
>>

>> � lets call them 7& 8 by clipping them together to one of the

>> existing ping of the RJ25 connector?
>>

>> � In that case would you recommend clipping 1& 7 and 5& 8?
>>
>>
>>
>>
>>
>> I�m not sure I understand your question, but I�ll take a run at it. My
>> verbosity is intended to improve the likelihood that you�ll get what you
>> need without having to go back& forth. My original recommendation was

>> simply oriented toward splitting any unused conductors (i.e., those not use
>> for signaling) into power and ground, and merging all the power wires into a
>> higher capacity, and doing the same for the ground. The MP01 already merges

>> 2 pairs this way, with pins 1& 2 merged to carry 12V, and pins 5& 6 merged

>> to carry ground. If you had more pins, you could merge more conductors, but

>> you don�t, and so you can�t.

>>
>>
>>
>> First, since 6 of the 8 CAT5 wires are accounted for in the MP01 H/W
>> description, there is only 1 pair (2 wires) remaining). To keep it simple,

>> since pins 1-6 are spoken for, 7& 8 seem like the obvious candidates to

>> leave out (clip). However, the pins are numbered on the connector, not the
>> cable, which is colored-code according to pairs of wires.
>>
>>
>>

>> In the attached image named �RJ45 Pinout (Zytrax.com).jpg� you will note

>> that there are two different wiring standards that are commonly used with
>> CAT5 and RJ45 connectors. Since you are using CAT5, but *not* RJ45, you

>> don�t have to worry about splitting the green pair (or any pairs), for
>> example, as shown in the image named �RJ45 Plug with Cable
>> (Nullmodem.com).jpg�.

>>
>>
>>
>> What is most important here is that you think of the CAT5 cable as having
>> four PAIRS of conductors. This is especially true for the telephone (ring&
>> tip) conductors. You should keep them as a pair, because the wires in the

>> pair are twisted (hence, �twisted pair) in such a way as to be essentially

>> orthogonal to each other (and to the other pairs), so as to reduce
>> noise/crosstalk.
>>
>>
>>
>> In your case, all the other pairs are available to carry power and ground.
>> Although it would be no big deal to use all three remaining pairs for power

>> and ground if you attaching to a socket, it�s quite a different story with

>> an RJ25 plug. As far as I know, an RJ25 plug (which is like an RJ11 that
>> can accommodate three pairs) can accommodate ONLY three pairs or less. In

>> your non-standard application, it doesn�t really matter WHICH three of the

>> four pairs in a CAT5 cable, as long as the other end is wired compatibly.
>>
>>
>>

>> In the image named �RJ11, RJ14, RJ25 pinout with CAT5 colors
>> (Neutrino.phys.ksu.edu).jpg�, you can see that all the pairs have been split

>> up except for the center pair. This is because each pair is carrying a
>> signal (presumably voice, like on a multi-line telephone), and this pin-out
>> ensures that each pair carries mating Tx/Rx signals for one phone line.
>> Note that the brown pair is the one omitted from this picture, which would
>> mean it got clipped. In your case, you only have one signal pair, so I

>> would probably not split up the pairs used for power& ground. It�s hard

>> enough to crimp this type of plug without complicating things by having to
>> split wire pairs.
>>
>>
>>
>> Personally, I would choose three consecutive pairs that simplify the

>> crimping operation, and clip off the fourth pair (since there�s no way to

>> connect it to the RJ25 plug). Make sure that the center pair is the one for
>> voice. That leaves a full pair dedicated to 12V, and another pair dedicated
>> to GROUND, which simplifies construction by NOT splitting the pairs up as
>> shown on the color-coded connectors.
>>
>>
>>
>> To reiterate, in your non-standard application, the most important things
>> are to:
>>

>> Use a full pair for the center pins (3& 4 on the RJ25) that carry voice,

>> and
>> Wire both ends of cable in a compatible way.
>>
>>
>>
>> Also, I would check the cable for continuity end-to-end, and ensure there
>> are no shorts between 12V& ground, 12V& either voice conductor, ground&
>> either voice conductor, or between voice conductors.
>>
>>
>>

>> I haven�t seen any discussion about whether you�re using solid or stranded

>> CAT5 cable. Solid is much easier to crimp correctly, but it is also more
>> brittle and prone to fatigue, which is why CAT5 patch cables are always
>> fabricated from stranded cable.
>>
>>
>>
>> It would be advisable to make a wiring diagram of your cable, use it when

>> you build the cable, and then save it permanently (I�d probably keep a copy

>> handy, near one end).
>>
>>
>>
>> It would be nice if someone else would jump in to confirm or deny my

>> assertions here, especially if I�ve left out anything important.

>>
>>
>>
>> Dave Duchesneau
>>
>> d...@crisis-force.org
>>
>>
>>
>>
>>
>> ________________________________
>>
>> From: Carlos Rey-Moreno [mailto:cr...@ehas.org]
>> Sent: Thursday, May 24, 2012 10:06 AM
>> To: village-...@googlegroups.com
>> Cc: d...@crisis-force.org
>>
>>
>> Subject: Re: [vt-dev] A couple of general questions
>>
>>
>>
>> Finally we got shielded 8-wires Cat5, and I was wondering what happen if
>> there is short circuit in the cable, or in the router. Will the PoTL adapter
>> work as a fuse, or will it go all the way to the regulator burning both the
>> cable and the PoTL?
>>
>>
>> By the way, sorry @Dave I think I got you recommendation wrong. According to
>> http://wiki.villagetelco.org/images/3/39/MP01_Hardware_Description_2010-05-02.pdf

>> the ping 1& 2 of the connector should carry 12V, 3& 4 the Phone (ring&
>> tip) and 5& 6 0 Vdc input (MP01 Gnd). Your recommendation was using the two
>> wires that we are not using lets call them 7& 8 by clipping them together

>> to one of the existing ping of the RJ25 connector? In that case would you

>> recommend clipping 1& 7 and 5& 8?

[Dave Duchesneau]

> ...that is part of the motivation to switch to a 24V PSU

> so that 4-wires would work in most cases.

Just a different PSU "accessory", but without changing the MP side of
things, right? So, will the MP2 be fully compatible with pin-out and
voltage spec?

> For using CAT5 with an RJ12 , I have a simple rubric. \
> Keep the primary/secondary colours i.e. clip the brown pair.

> Wire the pairsalphabetically according to colour.

> Blue pair, Green pair, Orange pair.
> Not terribly scientific but easy to remember.

That's great! I love it.
"Easy to remember" is worth a lot.

Dave Duchesneau
d...@crisis-force.org

-----Original Message-----
From: village-...@googlegroups.com
[mailto:village-...@googlegroups.com] On Behalf Of Song, Stephen

[Song, Stephen]

On 25 May 2012 17:46, Dave Duchesneau <d...@crisis-force.org> wrote:
>> ...that is part of the motivation to switch to a 24V PSU
>> so that 4-wires would work in most cases.
>
> Just a different PSU "accessory", but without changing the MP side of
> things, right?  So, will the MP2 be fully compatible with pin-out and
> voltage spec?

Exactly. Same Mesh Potato, different PSU.

The MP2 will hopefully be even lower power than the MP and will have
an integrated power/phone/data port that will use a single CAT5 cable
to carry all three. So what is now the PoTL adaptor that ships with
the MP will have both an RJ11 and RJ45 jack on one side and power and
PoTL/E connector on the other. So with standard lengths, you might
get away with no crimping at all which I have to say would not break
my heart. :-)