[chbot] Choc Fish Challenge #5

[m.beckett at amuri.net]

Gents
We have had a hack at this at work.
We work out 4km required to label both ends.

If you want the jumpering undone so they become individual, it needs a 
5th km.

We can explain how, but its a long email, and the phones keep ringing.


Mark


On Sun, 4 Sep 2011 21:55:00 +1200, Synco Reynders wrote:
> Hi Mike,
> I see you're a fit (or going to be a fit) guy after doing this... Cos
> the next job your the boss has is a 300 wire cable <very subtle hint>
> :-).
> Nice try, but you may need a bit more optimisation.
> /s
>
> On 4 September 2011 21:44, Michael Field <hamster at snap.net.nz> wrote:
>> I've made a start.... this is flawed (at the end of step 2 we 
>> haven't
>> definitively identified the bundles at the far end) but might 
>> inspire
>> somebody. My guess is that you need to use uneven wire counts in 
>> each bundle
>> you can glean more information....
>>
>> But I'm pretty sure that the divide into three groups and wiring up 
>> two is
>> the correct starting point...
>>
>> Mike
>>
>> First step
>> Separate the cables into 3 bundles of 40, short all cables in the 
>> bundle
>> together Connect each end of the battery terminals to one bundle of 
>> 40
>> (leaving one bundle unconnected).
>>
>> Walk to the other end.
>>
>> Connect light to a random wire, and try to get a circuit by 
>> connecting to
>> each of the other wires. If nothing lights, try another wire.
>>
>> When you get a light, you will then be able to move one jumper 
>> around to
>> find which 39 other wires are also in that bundle. Do the same with 
>> the
>> other terminal of the bulb.
>>
>> You will then have three bundles of 40. One you will be know more 
>> about
>> (it's not connected at the other end) but you won't know which 
>> bundle is
>> connected to the positive terminal, and which is to the negative (oh 
>> for an
>> LED or meter).
>>
>> Second step
>> For each bundle of 40, divide it into two sets of 20, and jumper 
>> together.
>> Jumper two bundles of 20 from one of those connected to one of the 
>> battery
>> terminals together, jumper each bundle of 20 from the unconnected 
>> pair to a
>> bundle of 20 that is connected to the battery.
>>
>> Walk back to the other end
>>
>> Use the bulb in series with the battery to separate the starting end 
>> into 6
>> bundles of 20.  you will also be able to work out which bundle was 
>> connected
>> to which battery terminal, accurately identifying both ends of the 
>> bundle.
>>
>> Label each cable.
>>
>> Step 3 & 4
>> Deal out the cables again 3 or 4 from each bundle of 20, into new 
>> bundles of
>> 40. Repeat. The above process, walking another two trips
>> This will allow you to divide the cables into 36 bundles of three or 
>> four.
>>
>> Step 5 & 6
>> Deal out the cables again bundles of 3 or for , into new bundles of 
>> 40.
>> Repeat. The above process, walking another two trips
>> This will allow you to identify individual cables.
>>
>>
>> On 4/09/2011 7:48 p.m., Synco Reynders wrote:
>>
>> As I was pulling through some wires today I remembered this classic
>> challenge...
>>
>> A 120 wire cable has been laid firmly underground between two
>> telephone exchanges located 1km apart.
>> After the cable was laid it was discovered the individual wires are
>> not labeled. There is no visual way of knowing which wire is which 
>> and
>> thus connections at either end is not immediately possible.
>> As trainee technician your boss has asked you to sort it out and
>> identify / label the wires at both ends. You only have a battery and
>> light bulb to test continuity and tape/pen for labeling the wires.
>>
>> What is the shortest distance in kilometers you will need to walk to
>> correctly identify and label each wire?
>>
>>
>>
>>
>> _______________________________________________
>> Chchrobotics mailing list Chchrobotics at lists.linuxnut.co.nz
>> http://lists.ourshack.com/mailman/listinfo/chchrobotics
>> Mail Archives: http://lists.ourshack.com/pipermail/chchrobotics/
>> Web site: http://kiwibots.org
>> Meetings 3rd Monday each month at Tait Radio Communications, 175 
>> Roydvale
>> Ave, 6.30pm
>>
>> When replying, please edit your Subject line to reflect new content.
>>
>
> _______________________________________________
> Chchrobotics mailing list Chchrobotics at lists.linuxnut.co.nz
> http://lists.ourshack.com/mailman/listinfo/chchrobotics
> Mail Archives: http://lists.ourshack.com/pipermail/chchrobotics/
> Web site: http://kiwibots.org
> Meetings 3rd Monday each month at Tait Radio Communications, 175
> Roydvale Ave, 6.30pm
>
> When replying, please edit your Subject line to reflect new content.