Stickig a pigtail into a card..

Hey everyone... first post here...

I just moved from my old room... I also just discovered I can get almost no signal with my laptop on the desk in my new room.. as I intend to use it mostly there, on the desk,i thought i'd found a way to get some signal there rather than waltzing the thing all around the place to find a line of signal everytime i want to use the computer... there's pretty good, if patchy signal in the room.. so i think what's getting in my way is the desk itself (the room is a story higher and about 20 mts away from the wireless router)...(and by '20 mts' i mean 'anything between 10 and 30 mts' and by cool I mean totally sweet *)
I'm not the best at estimating distances

anyway, i did my googling and came up with what seem like a couple decent rather simple antennas that i think would do the trick, but I came up with the main obstacle, there's no antenna connector in my wireless PCMCIA card
SO... would somebody please help me out on how to solder a pigtail into this thing... I actually mean where should it be soldered?... any other bit of useful info will be greatly appreciated..

I hope this post is clear enough, here cometh the pics







JCane

Welcome to the forum!

Soldering a pigtail to most PCMCIA wireless cards isn't too difficult, just bear in mind you want a very fine tip soldering iron and it helps have have a bit of soldering experience. Unfortunately the photos are a bit small to pick up any detail on. Are you able to post a higher resolution picture? If so I could draw some diagrams on it. Placing the card on a scanner will do the job nicely.

Follow the tracks from the antennas (those gold 'C' shaped designs on the end) and you should find each one leads through a tiny chip capacitor into a small 6 or 8 pin surface mount IC.

Many PCMCIA cards have solder pads for external connectors as well as inbuilt antennas etched on the PCB, and you can solder the pigtail directly to these pads. You might need to solder the capacitor into a different position to direct the signal to the external connector instead of internal one.

If yours doesn't have provision for external connectors then you will need to cut the tracks near the inbuilt antenna before it gets to the capacitor, scape some of the green solder mask off and solder the pigtail directly to the track.

Quite a few PCMCIA cards only seem to transmit using one of the two antennas. If one is labelled Main or similar use that. If they aren't labelled, you might need to try connecting to both to see which one gives the best performance.

I did this to a Senao card once and even though it already had an external antenna connector the process is pretty similar. View pictures here

If you have some higher res pictures that would surely help.

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Jeremy

Marlborough WiFi Project

here it goes... this is the best def i got now.. if its not enough ill try and scan it..

Good photos! I've edited one for you, try performing the steps in thie diagram below

Do the same for both antennas and test connectivity. If there is any noticable difference, use the one that gives you the most reliable connection.

Attached Images

 

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Jeremy

Marlborough WiFi Project

that's really great, thank you so much Lamb
I've got a couple of questions tough, just to make sure. after i cut the on board antenna i could always re-enable it by joining the two cut sides with solder, right?
AND.... I should first make the antenna and only then i can test this thing out... that wasn't much of a question actually
lastly..how much cable is it safe to use between the card and the antenna... would 1-2 mts of RG58 be ok? or RG213?.. because if i want to avoid as many obstacles as possible, a long cable would come in handy
cheers

JCane

For sure!

Good point! I'd avoid using RG58 unless you are certain that the stuff you have is microwave rated, and I wouldn't use much over 2m. RG213 is OK for short runs although it's pretty thick stuff. If you can dig up any LMR series cable that would really be ideal, LMR195 is pretty flexible and would do the trick nicely.

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Jeremy

Marlborough WiFi Project

the thing is i had already settled for a nice looking mini antenna that seems to have pretty good feedback, and it uses rg58, dyou reckon i should use it for the antenna and the another type of cable from it to the card or just plainly reject rg58 and find another ant?

hey.. already solved.. thank you very much... followed your directions, attached an rg58 pigtail...
you were right about rg58 though.. i tried to make it wok with about 1mt cable from the card to the antenna and it qouldn't even pick the tiniest signal... trimmed it to about 30 cm and it's working pretty good..(after I made it a dish with some tinfoil that is)
again thanks

Hello Everyone!

First post, so please be gentle...
The problem is the same, this time with a 3com 3CRSHPW696 card. Based on the thread i have a pretty good idea what to do, i just need to be re-assured that i won't necesarrily screw up my card...
Anyways, here's how the card looks like:


The yellow squares show what i think to be the capacitors. I plan to scrape the original PCB antenna at the red line, then solder the signal lead to the blue spot, and the ground to the green spot. Would that work?
Thanks in advance!

Timoti