Extending a 2.4Ghz Antenna

I interpret your description of the issue slightly different than MK. I see the antenna as being outside the package.

The dotted area is the sealed RX controller. There is a short connection to the antenna. Is there sufficient cable length to install an RF connector in the coax? You could then use the existing antenna (connector and extended cable) or a new antenna.

Hi everyone thank you for your quick responses.

colporteur. - Your interpretation is correct

The antenna consisits of only a wire that extends approximately 60mm from the encapsulated module.

The insulated sheath has been remove from approx 30mm from the end of the wire but still has a clear plastic sheath.

Is there any way I can install a RF connector in the coax

So the coax has two insulation layers.  The dark outside skin and a clear inside skin. Inside the clear skin is the coax braid, a center core dialectric and a center conductor.

Your description has an extra insulator between the plastic jacket and Braid.

I have put connectors on coax but only as small as RG-58. I've done BNC on this cable that allows a male and female connection. I have read some content from some pretty experienced antenna guys. Maybe someone with experience might be able to suggest part numbers for a connector.

Unfortunately it will be tricky to place inline connectors. There are quite a range of thin coaxes (some only differing by half a millimeter more or less diameter), so the precise coax diameter needs to be known to determine what connector could fit, and even then, tools or intricate soldering would be needed. Some of the connectors are not available for inline use either. 

Even if it was done, there could be side-effects. 

 I could write a lot more, but long story short, there could be detuning effects, but if the transmitter is only needed to be close to the antenna, then even a lower range detuned antenna might be fine. I don't know though, since there are so many factors outside of any control.

There's just not enough information for me to suggest much more, and I still don't understand why the entire unit can't be moved to be closer to the transmitter, so that the antenna (the most sensitive part of the equipment) doesn't need to be touched.

Unfortunately it will be tricky to place inline connectors. There are quite a range of thin coaxes (some only differing by half a millimeter more or less diameter), so the precise coax diameter needs to be known to determine what connector could fit, and even then, tools or intricate soldering would be needed. Some of the connectors are not available for inline use either. 

Even if it was done, there could be side-effects. 

 I could write a lot more, but long story short, there could be detuning effects, but if the transmitter is only needed to be close to the antenna, then even a lower range detuned antenna might be fine. I don't know though, since there are so many factors outside of any control.

There's just not enough information for me to suggest much more, and I still don't understand why the entire unit can't be moved to be closer to the transmitter, so that the antenna (the most sensitive part of the equipment) doesn't need to be touched.

Also orientation could improve things, e.g. try rotating the device by 90 degrees so antenna is up; it might improve or it might worsen the situation. Plus I've no idea if the white part of the photo is a metal panel. If it is, then antenna perpendicular to the panel would be a good idea, or mount a lot further away from the surface of the panel.

My "solution" to soldering in-line connectors onto coax is to buy a pre-made cable and cut it for what I need.  I then would solder the modified cable in place of the existing run.  SMA on RG316 is just too tiny to be fun.

shabaz's comment on the antenna orientation is real.  I've read that there is 20dB of attenuation between horizontal and vertical polarization (orientation). You could also explore using a directional antenna - if that fits the application.

Hi All,  thank you for the orientation suggestions - have moved it around but no discernable difference.

The White background is just a sheet of white paper to improve the photo.

Unfortunately the Controller is fixed physically, as moving the controller would be the solution.

Attached is a pic of the Clear encapsulated  controller showing the Aerial wire connected to the PCB, however I am not confident enough to be able to remove the encapsulation to get to the aerial connctor.

So I am left with attempting to somehow connecting the Wire Braid and the Centre Conductor  to a Male Aerial Connector.

The outside diameter of the plastic Di-electric Insulator is 0.7mm.

Sounds like it is too detailed an operation to achieve, I am sure this is not the first time this scenario has occured.

Thank you 

Hi kmikemoo

thank you for your solution.

So I would have to remove the encaspulation from the PCB board around the on board connector?

You might be able to find a complete replacement antenna, because the connector looks like U.FL, which is fairly popular. However, it might not be U.FL, there are several connectors which all look approximately similar, but with different dimensions. 

For instance this cable has a U.FL connector on one end:

The other end of that cable has a connector that is called RP-SMA:

RP-SMA is fairly standard for 2.4 GHz antennas, and you can get quite large ones like this (make sure it is 'RP' though because some are just "SMA" and not "RP-SMA" and they look extremely similar at first glance. The RP-SMA ones will likely have the text RP in the part number:

That one is 380 mm long! You can get much smaller ones if that one is not practical.

I've not checked, but you should also be able to get extension cables with RP-SMA plug on one end, and RP-SMA socket on the other end, if that short cable and large antenna are not enough.

There's loss on long cables (and on the connectors), so it's good to use as short as possible.

All of this assumes that the connector on your board is U.FL. If you get one of those cables, you'll be able to compare them visually (there are no part markings on those connectors, so it is hard to be sure without visual comparison of sizes).

Also, unplugging that connector needs care.. it needs to be lifted vertically, but it snaps in so a bit of force is needed, but not too much force.

Splicing into the existing wire is not really feasible at 2.4 GHz, there will be a lot of loss, so really all of that should be replaced.

Hi sparkyjack .  Yes.  You will need to remove that weird jelly coating.  Depending on how well the manufacturer prepared the surface, it can be an arduous process or it will peel like an orange - okay, but no where near like a banana.  I use Acetone and Q-Tips to clean up the residual.  You only need to remove "just enough".

From there, I'm going with "What shabaz  said.,"  I'd spend the $7 (plus shipping) and roll the dice on the ufl to rp-sma connector that Shabaz recommended.  With the RP-SMA connector... you have many options.