Cabling

[wolsty]

If I can avoid the usual Easter rush to DIY, I thought I might have a go at running some cabling from my downstairs office to the upstairs living room. I'd like to have a LAN connection between my laptop (normally in my living room) and my desktop (next to the BT socket in the office) machines and an RS232 cable connecting my Hummie (living room) to my desktop. I haven't a clue what to order from the component supplier. Any suggestions and guidance would be most welcome.

I'd earn some Brownie points, because Franny the Dragon would also be pleased to see the back of the old desktop machine currently on the floor next to the tv.

 

[PoloMint]

How far is the distance?

For the network you need Category 5 cable. Also known as Cat5 and comes either UTP (Unshielded Twisted Pair) or STP (Shielded Twisted Pair). Unless you are running it past loads of microwaves and fluorescent lights then the unshielded stuff should do.

In ready made up lengths this cable is sometimes very pricy, so if you have a reasonable distance you might well be better off buying a drum or 50m length. You will then of course need to put the connectors on each end. You will need RJ45 connectors and you really should get a crimping tool rather then trying it without one. Even with a tool get at least 4 times the number of connectors you actually need, there’re quite cheap and by the time you have broken two and wired two up incorrectly you will need the extra ones.

Have you done networking before? Do you want the cable to be crossover or straight? If you have got a hub you will need it straight, if you are connecting PC to PC direct (like it sounds like you are doing) you will need a crossover cable. For a straight cable just make sure the colour of cable in each pin in the first connector matches the colour of the cable going to the same pin the other connector. For a crossover cable do a web search on how to make one, essentially you just cross the pairs (being two sets of twisted pairs in the cable). Of course if you buy ready made up cable you wont have this problem.

For the serial cable I’m not really sure, never extended one of those. I think it would be best to get a ready made up one. American websites sell them in lengths up to 25m, I didn’t see a UK supplier in the quick search I did, but there probably is one that I missed.

 

[wolsty]

Thanks Polo Mint. That's very helpful.

At the moment I have a crossover cable (my son got it from one of his friends) running from the office, up the stairs, across the dining room and into the living room. Provided that I sit close enough to the living room door, it gets round the problem, but it's inconvenient to everyone who was to wriggle past it and sooner or later someone will trip over it and break something. And, what's more, I can't see the tv. I guess the total length of run from the office to the loft and down to the aerial socket in the living room at each end for connection to the pc's, leaving a length at each end for connection to the pc's is about 25 metres A bit less for the serial cable.

I've been looking at threads about lengthening serial cables on other forums. One posting suggests that you can cut a normal cable and insert a length of four core telephone cable up to 20 metres. That solution seems a bit Heath Robinson to me and I was wondering if it would be possible to use some of the burglar alarm cable I already have spare, or some of the UTP I'll have to buy, and make up my own. I'm reasonably handy with a soldering iron. What connectors would I need?

 

[wolsty]

And another thought. If I were to use STP cable, would I not have to ground the sheild? How would I do that in a 4 pin plug?

 

[PoloMint]

RS have a ‘RS-232 Cable Kits - assembly tools’ (item 202-420) which seems to have one male and one female 9pin connectors not already attached to cables. However it also says that the cable lengths are terminated with pre crimped pins, so I’m not sure if you have to use the cable that they supply or not. If the kit could be adapted to use your own cable it might be a tidy way of doing it. Some pre made serial cable ends can be unscrewed, and you could then take out the cable that is there and soldier in new stuff, but the pin connectors are very close together, so it would test your soldering skills.

The only concern I would have with using UTP cable for serial cable is that, being twisted, the actual cable length of each core is much much longer than the whole cable length (as the cores are wrapped around each other inside, far far more than phone cable). I’m not sure how powerful a serial port is, but 25m of UTP cable is going enormously longer (and so higher resistance) than a standard cable length, I really don’t know if this would be a problem (but it would certainly be with a parallel cable).

What type of phone cable was the other thread referring to? ‘Proper’ phone cable is actually Cat3, it’s the same idea as Cat5 cable but the twists are not as often, so 25m of cat 5 cable has much more cable in it than 25m of cat3, this might also be what you alarm cable is. It might be a good cable to use, still shielded, but less resistance than cat5. But I don’t think it would be a good idea trying with ordinary cheap phone cable.

STP is not grounded, the shield is just a wire mesh that surrounds the cores, between them and the outer plastic covering. It is just cut away in the connector along with the plastic covering. You can normally tell STP by looking at it, as it is slightly more round that UTP where you can see the shape of interior cables somewhat more. At home we have both, but that is really just chance as to what was available at the time.

Edit: and the link for the RS stuff http://rswww.com/cgi-bin/bv/search/...Type=images&SearchText=202-420&quickSubmit=Go

 

[wolsty]

Thanks again Polo Mint. Most interesting and helpful.
The other thread is at: http://64.235.50.126/~takula/forum/showthread.php?s=&threadid=71739 and the cable mentioned is alarm cable. Later comments draw attention to the problem of resistance and the fact that WCE seems not to work on long runs (is this to do with power supply to the season?). The main point of my running the cable to my desktop is to reduce clutter in the living room, but it would be an own goal and waste of money and effort if the setup doesn't work. I'm inclined to run my spare cable at the same time I install the UTP/STP and see what happens. I'll post again when I've done the work and let you know how well it's gone.

 

[w hole]

Hello Woltsy

Have you considered 'wireless' it might be a bit more expensive, but it seems to be the way things are going, and it would give you much more flexibiliy, and even perhaps a few brownie points for not messing up the skirting board.

Regards

W. Hole

 

[wolsty]

I'm seriously considering wireless, but funds are a bit stretched at the moment. My eldest daughter is getting married in May and expenses so far - wedding dress, stag night, hen night, suit, wife's dress, not to mention wife's hat - are doing serious damage to our finances. Faced with spending £150 on wireless networking, which will last several years and give hours of pleasure or spending £150 on a hat, which will be worn once and then occupy a large part of the wardrobe for eternity, which would you choose? Perhaps, when the bank account has recovered, I'll be able to think about 'boys'toys'. Since the trunking is already in place, I thought I'd do a quick and dirty fix to get me through the next few months.

 

[Channel Hopper]

Im sure once the wife is finished with the hat and dress, you might be able to squeeze into it for the Sunday (and maybe Friday ) nights down the

GREAT WESTERN KERNOW
HARLEY-DAVIDSON RALLY
2 - 3 - 4 JULY 2004
AT THE
MONKEY TREE HOLIDAY PARK
REJERRAH - NEWQUAY - CORNWALL
Friday is 70's Disco Boogie Night
Saturday Night live 'POINT BLANK' Its a Rock thing''
Sunday Night is American Music & Fancy Dress

 

[wolsty]

I might. But my bum looks big in the dress.

 

[Channel Hopper]

OK then, donate it to Rick Steins Padstow Luvvie fund

 

[rolfw]

£50 plus vat will get you a wireless a pair of PCI and PCMCIA units, 11MBPS.

 

[wolsty]

@ Rolf

I doubt if I could install cabling for that. Could you PM me details, please?

 

[wolsty]

The RS232 issue is academic now. I've just installed the Humax Emu. It's the best news in ages. Top banana.

 

[Channel Hopper]

The RS232 issue is academic now. I've just installed the Humax Emu. It's the best news in ages. Top banana.

Ive had a look at Mr Dudes package, but cannot get any of it to work

Sticking with the 30W stuff on Emulatorek 10a for the minute, though Calle13 appears to have gone downhill in quality programmes

 

[wolsty]

@ Channel Hopper.

I haven't had any problems with Mr Dude's stuff. I'm running it on a Vaio 2600 laptop under XP Professional. I have to use a serial/USB converter as there's no 9 pin connector on the lappie but, even then, the software has all functioned correctly first time. I can't offer any suggestions as to why you're having difficulty.

The EMU was downloaded from a site given in this thread on Dudez:http://www.satdudez-forumz.com/forum/showthread.php?s=&threadid=52050&perpage=15&pagenumber=1

It took a bit of fiddling, but it's running faultlessly now. The thread also gives some information on problem solving. It's worth spending an hour on.