WiFi antenna mod

[sansjunk]

<I am re-posting a thread I posted on another forum>

Over the last weekend I received the pair of cheap Tyco wireless antenna I had ordered and I went ahead with the mod for replacing the stock antenna of my FT3. I thought my attempt was a disaster since I ended up uprooting one of the components from the WiFi card while trying to clean the mess of glue from it. It probably was a capacitor or a resistor and it was impossible for me to solder it back. But to my surprise the card still functions. Lucky me!

Anyway the outcome of the new antenna was mixed since there was no discernible increase in the signal strength but now I find that the pad holds the WiFi connection up even if signal strength drops considerably. For instance earlier with the original antenna if I took the pad to a distance of about 20 feet with 3 dry walls in between the signal would drop to about -80 dBm and it would immediately drop the connection. Now with the new patch antenna the signal is around -79/-80 dBm but the connection stays up (albeit with a lower speed). However I am not sure now if this improvement is due to the new antenna or because of the missing component!

The patch antenna comes as a pair and I ended up using only one with the white wire which I noticed is used as the "Main" antenna while the other is used as "Aux" (in laptop WiFi cards). I couldn't find a suitable place on the WiFi card to solder the Aux antenna - perhaps it doesn't support it. BTW I also notice now that the WiFi chip doesn't get as hot as it used to - I haven't paid much attention to this so I could be wrong.

Here are some pictures I took while modding.

Picture showing the new antenna soldered in place of the stock one. Also shows the place where the component fell off.

Shows where I placed the antenna. I had to choose the lower part of the pad since there's no place on the upper part unless you move the WiFi card away. Upper part would probably be a better place.

Shows the completed mod with the battery overlapping the antenna. The wire is quite long and I just ended up running it around on the battery a couple of turns - probably not the best idea!

The last one shows the stock antenna.

 

[tbod]

Having just come from apad,tv I have the strangest feeling of deja vu...

Your soldering needs a bit of work, it looks like you might have wiggled the lead a little while the solder was still molten. Were you holding the cable?

Before I replaced all my fingerprints with burns and scar tissue I invested in one of those 'third hand' jobbies with little clamps to hold PCBs and other things in place. Mine has quite a large magnifying glass as well, it really helps...

 

[deeboi]

Those 3rd hand things are a god send, I'll need to get one with a magnifying glass too, lol.

I would unsolder that and try again m8, no offence intended as I'm not exactly an expert myself. It looks to me like your wires might be touching due to the fact there's quite allot of solder there and like tbod mentioned you might have wiggled the wire while still molten causing the solder to meet.

That in itself could have an effect on your results with the antenna.

A few tips I've learnt through the years are-

(for the sake of this, wire= antenna wire solder=soldering wire)

1. Wait for the iron to heat up fully
2. Expose a little more wire than you need.
3. Heat up the wire your about to solder then melt a little solder onto it to give it a little coating and trim off the very tip of the wire to make it neat or the size you require.
4. Remember not to keep trying and trying if it doesn't solder straight away, you don't want to melt the pvc casing inside the wires (or the wires will touch) or damage other components on the board your soldering to. (or components will fall out, lol)
5. If you don't manage to solder it straight away, allow it to cool down then start again.

Like I say I'm no expert, I've made all the above mistakes myself and learnt from them so might as well pass on the info.

(PS I'll also post this across the road too in the other post)

 

[kb7urx]

You need to loose about 2/3 of the feedline or you'll pay for it in losses!

Those 3rd hand things are a god send, I'll need to get one with a magnifying glass too, lol.

I would unsolder that and try again m8, no offence intended as I'm not exactly an expert myself. It looks to me like your wires might be touching due to the fact there's quite allot of solder there and like tbod mentioned you might have wiggled the wire while still molten causing the solder to meet.

That in itself could have an effect on your results with the antenna.

A few tips I've learnt through the years are-

(for the sake of this, wire= antenna wire solder=soldering wire)

1. Wait for the iron to heat up fully
2. Expose a little more wire than you need.
3. Heat up the wire your about to solder then melt a little solder onto it to give it a little coating and trim off the very tip of the wire to make it neat or the size you require.
4. Remember not to keep trying and trying if it doesn't solder straight away, you don't want to melt the pvc casing inside the wires (or the wires will touch) or damage other components on the board your soldering to. (or components will fall out, lol)
5. If you don't manage to solder it straight away, allow it to cool down then start again.

Like I say I'm no expert, I've made all the above mistakes myself and learnt from them so might as well pass on the info.

(PS I'll also post this across the road too in the other post)

 

[sansjunk]

Yes I had posted over on the other official forum but I find there's more activity here than there!

Thanks for all the tips deeboi.

Yes, I know I did a bad job on the soldering but its not as bad as it looks - at least there is no bridge between the center lead and the ground wire

@tbod, I was holding the wire and the WiFi card was dancing in the air so had a hard time getting to solder it! I was also thinking of buying a lens. Good advice on that 3rd hand with lens thingie - need to find out where I can get one of those!

@kb7urx, isn't it so that these lead lengths are intentionally long to match up with the wavelength of the signal? If not I can just the wire to required length to make it more neater.

 

[dart16]

@kb7urx, isn't it so that these lead lengths are intentionally long to match up with the wavelength of the signal? If not I can just the wire to required length to make it more neater.

I'll wait for KB to answer that one for you.......

 

[kb7urx]

In a perfect world, the feedline length should be no more than 1/4 wavelength long, minus the velocity factor...but we don't live in a perfect world. If we did, Velocity factor, Impedance, feedline losses and materials that go into making the feedline would'nt be an issue
Basically any random length of feedline will work but dealing with losses at output levels in the 10-20 mw range(usually expressed as dBm or Decibels per meter) doesn't leave us much to play with when you consider losses at -3dB, that's half your power lost!
Now lets consider your received signal. using 0dB as our point of reference, -80dB is a very miniscule signal, However since the Phase-modulated data is operating in Spread-Spectrum mode, the signal might be buried in the noise floor, but still useable....that's why you can get away with -70 to -80dB signal levels and still be connected and passing data.
Too much noise tho can swamp even the best engineered SS receiver front-end, causing multiple ACK retries or even complete packet losses! So, the caveat with respect to noise is too many cordless devices that operate at or close to the 2.4Ghz band can and do interfere with your WIFI including the biggest offender, your microwave oven that just happens to work at 2450Mhz...that's 2.45 Ghz...right in the middle of the GSM band, some putting out as much as 3-5 kilowatts for industrial versions.

So as you can see, you're fighting a battle of diminishing returns, just make the most of what you have or what technology offers.
And yes, reduce your feedline length to only what you need to get the WIFI adapter connected to the antenna and try to position the antenna as far as possible from any metallic objects, including the LiPo batteries!

Sorry guys....didn't mean to write a book but some things needed a bit of explaining!
Happy Trails!

 

[dart16]

In a perfect world, the feedline length should be no more than 1/4 wavelength long, minus the velocity factor...but we don't live in a perfect world. If we did, Velocity factor, Impedance, feedline losses and materials that go into making the feedline would'nt be an issue
Basically any random length of feedline will work but dealing with losses at output levels in the 10-20 mw range(usually expressed as dBm or Decibels per meter) doesn't leave us much to play with when you consider losses at -3dB, that's half your power lost!
Now lets consider your received signal. using 0dB as our point of reference, -80dB is a very miniscule signal, However since the Phase-modulated data is operating in Spread-Spectrum mode, the signal might be buried in the noise floor, but still useable....that's why you can get away with -70 to -80dB signal levels and still be connected and passing data.
Too much noise tho can swamp even the best engineered SS receiver front-end, causing multiple ACK retries or even complete packet losses! So, the caveat with respect to noise is too many cordless devices that operate at or close to the 2.4Ghz band can and do interfere with your WIFI including the biggest offender, your microwave oven that just happens to work at 2450Mhz...that's 2.45 Ghz...right in the middle of the GSM band, some putting out as much as 3-5 kilowatts for industrial versions.

So as you can see, you're fighting a battle of diminishing returns, just make the most of what you have or what technology offers.
And yes, reduce your feedline length to only what you need to get the WIFI adapter connected to the antenna and try to position the antenna as far as possible from any metallic objects, including the LiPo batteries!

Sorry guys....didn't mean to write a book but some things needed a bit of explaining!
Happy Trails!

Wow! I'm glad I left it to you KB....I would just have said shorten it to reduce your losses, its not important when using these output powers!

 

[kb7urx]

Wow! I'm glad I left it to you KB....I would just have said shorten it to reduce your losses, its not important when using these output powers!

Yea...maybe...but isn't it nice to have a little knowledge thrown in with it, instead of having to wallow in ignorance?
Maybe it'll provoke some thinking and possibly even....dare i say..."research"!

 

[dart16]

Yea...maybe...but isn't it nice to have a little knowledge thrown in with it, instead of having to wallow in ignorance?
Maybe it'll provoke some thinking and possibly even....dare i say..."research"!

Oh yes.. I do agree....but perhaps phase modulated spread spectrum and SS front end swamping is not quite the right place to start.....I guess you lost most people at velocity factor!

 

[kb7urx]

Oh yes.. I do agree....but perhaps phase modulated spread spectrum and SS front end swamping is not quite the right place to start.....I guess you lost most people at velocity factor!

Just trying to be thorough!

Ya know, some of the members on here might want to learn something about what they are trying to accomplish rather than just copying something that someone else did. To me, it's a far richer experience when I'm able to explore more of the inner-workings of something at least moderatly complex. I come away with alot more experience than just following "Tab A into Slot B"!

 

[tbod]

Just trying to be thorough!

Ya know, some of the members on here might want to learn something about what they are trying to accomplish rather than just copying something that someone else did. To me, it's a far richer experience when I'm able to explore more of the inner-workings of something at least moderatly complex. I come away with alot more experience than just following "Tab A into Slot B"!

I totally agree - I came up with a little saying which I try to pass on whenever I can.

"What I'm told, I forget. What I read, I remember. What I do, I understand."

 

[dart16]

I totally agree - I came up with a little saying which I try to pass on whenever I can.

"What I'm told, I forget. What I read, I remember. What I do, I understand."

Yessssssss....but if you had to apply newtons relativity theorm to the quantum mechanics of a nuclear detonation on a wet friday in June you wouldn't remember much would you? On the other hand, if someone TOLD you not to press the detonate button...you would pretty well remember it wouldn't you? My point is a little inspiration is great and mostly welcomed... but word it without jargon or else people will loose interest.

 

[kb7urx]

Yessssssss....but if you had to apply newtons relativity theorm to the quantum mechanics of a nuclear detonation on a wet friday in June you wouldn't remember much would you? On the other hand, if someone TOLD you not to press the detonate button...you would pretty well remember it wouldn't you? My point is a little inspiration is great and mostly welcomed... but word it without jargon or else people will loose interest.

Only those who weren't interested in the first place!

These forums are for creative and explorative minds! If you have knowledge...share it. If not...STFU! I tire of your simplistic ignorance and condescending remarks!
Just because you know a little, doesn't mean the rest of us have to suffer only your opinion, which by the way, holds little if any significent information.

 

[dart16]

Only those who weren't interested in the first place!

These forums are for creative and explorative minds! If you have knowledge...share it. If not...STFU! I tire of your simplistic ignorance and condescending remarks!
Just because you know a little, doesn't mean the rest of us have to suffer only your opinion, which by the way, holds little if any significent information.

These forums are for people who have a problem with their FT3's and want to be given an answer on how to fix it not to learn about the intricacies of particle physics....pi$$ off to 'New Science' magazine.

Thanked twice huh......i can see why that is.

 

[dart16]

Only those who weren't interested in the first place!

These forums are for creative and explorative minds! If you have knowledge...share it. If not...STFU! I tire of your simplistic ignorance and condescending remarks!
Just because you know a little, doesn't mean the rest of us have to suffer only your opinion, which by the way, holds little if any significent information.

So let me ask the question....


Who else understands or even cares about WTF Phase modulation of spread Spectrum means????

or even swamping of frontends??

or even (and this one is a little easier) velocity factors?


answers on a post card please to.
Douglas
I'm a smarmy Yank who just loves to show off
I passed my Amateur licence so know everything about particle physics
Orofino, ID 83544
USA

 

[kb7urx]

So let me ask the question....


Who else understands or even cares about WTF Phase modulation of spread Spectrum means????

or even swamping of frontends??

or even (and this one is a little easier) velocity factors?


answers on a post card please to.
Douglas
I'm a smarmy Yank who just loves to show off
I passed my Amateur licence so know everything about particle physics
Orofino, ID 83544
USA

See....this exactly what I mean! If you had a modicum of intelligence, you'd know that Just because I have a amateur license doesn't limit my knowledge or experience to ham radio. My 7 year old had a general license.
If you bothered to ask, You'd find that Ham radio is just a hobby! my career has been in all phases of communications technology and electronics field service...but you didn't bother to ask for my credentials. You just assumed I was some "Smarmy Yank" with a ham radio license.
Get this you dumbass Limey....I put on my pants one leg at a time...just like you, so stop with the punk-assed, holier-than-thou attitude.
When you start contributing instead of knocking everyone, maybe you'll see my point. In the mean time, GET OFF MY BACK!

 

[dart16]

See....this exactly what I mean! If you had a modicum of intelligence, you'd know that Just because I have a amateur license doesn't limit my knowledge or experience to ham radio.

Who said it did?

If you bothered to ask, You'd find that Ham radio is just a hobby! my career has been in all phases of communications technology and electronics field service...but you didn't bother to ask for my credentials.

What has that got to do with answering the OP's question? It makes not one scrap of difference if you hold the senior comms engineer position in NASA, the OP wanted to know the answer to a simple question, a million people know that answer, its nothing special, he didn't want chapter and verse in how radio works.

You just assumed I was some "Smarmy Yank" with a ham radio license.

I didn't assume it....you are a smarmy yank with a ham radio licence, that is plainly apparent from your "I know all about this subject and I'm going to tell you all about it so sit still while I tell you all about it" reply

Get this you dumbass Limey....I put on my pants one leg at a time...just like you,

You are assuming I wear pants....which I don't, and you are assuming I am a Limey....which I'm not. But that's because you didn't bother to find out before you started spouting.

so stop with the punk-assed, holier-than-thou attitude.

kettle - black.... I advised the OP the answer without trying to impress him with my knowledge of the subject in question.

When you start contributing instead of knocking everyone, maybe you'll see my point. In the mean time, GET OFF MY BACK!

Just take a look at the record of thanks for your sorry contributions and then take a look at mine. It's a fair reflection on what people think of your trying to help them.
I'm only 'on your back' because you told me to STFU well you can FO.

 

[kb7urx]

Who said it did?

What has that got to do with answering the OP's question? It makes not one scrap of difference if you hold the senior comms engineer position in NASA, the OP wanted to know the answer to a simple question, a million people know that answer, its nothing special, he didn't want chapter and verse in how radio works.

I didn't assume it....you are a smarmy yank with a ham radio licence, that is plainly apparent from your "I know all about this subject and I'm going to tell you all about it so sit still while I tell you all about it" reply

You are assuming I wear pants....which I don't, and you are assuming I am a Limey....which I'm not. But that's because you didn't bother to find out before you started spouting.

kettle - black.... I advised the OP the answer without trying to impress him with my knowledge of the subject in question.

Just take a look at the record of thanks for your sorry contributions and then take a look at mine. It's a fair reflection on what people think of your trying to help them.
I'm only 'on your back' because you told me to STFU well you can FO.

Ya, and you can still STFU you pretentious bitch cuz I'm gone!
Tell all your other "buds" on here, they can go look up the info themselves because you don't have the intelligence or a helpful nature!

 

[dart16]

Ya, and you can still STFU you pretentious bitch cuz I'm gone!
Tell all your other "buds" on here, they can go look up the info themselves because you don't have the intelligence or a helpful nature!

Apparently its not me hat will have to STFU then is it?

Good riddance..If we ever get a question on phase mod Spread Spectrum we will have to live in blissful ignorance

 

[tbod]

Apparently its not me hat will have to STFU then is it?

Good riddance..If we ever get a question on phase mod Spread Spectrum we will have to live in blissful ignorance

If you really want to know how radio works may I refer you to one of my Heroes - Albert Einstein. When asked to explain how radio worked he said:

"You see, the wire telegraph is like a very, very long thin cat. You pull his tail in New York and his head is meowing in Los Angeles. Do you understand this? Well radio operates exactly the same way: you send signals here, they receive them there. The only difference is that there is no cat."

Sorry about my bad German accent, I can't help doing it when quoting Albert.

 

[sansjunk]

Wow, I was away a bit and my topic's got hijacked!
Anyway thanks for all the info about the lead length. The next time I open er up I'll reduce the lead length. I also plan to reposition the battery etc so I can try to mount the antenna on the top side (in landscape mode).