<p>The outermost plastic coating is not too critical; this primarily protects the braid from damage or exposure to elements. For the length involved in your image, you should be fine just adding heatshrink to cover that - and if you extend it over the pin you can get some strain relief too.</p>

CC BY-SA 4.0
2020-04-15T20:32:04.503Z
2020-04-15T20:32:04.503Z
Kralc
<p>I was swapping over my pigtails and part of the plastic coating around the coax came off. </p>

<p>The coax is still firmly soldered to the SMA connector - is this salvageable with some heat shrink, or do I need a new coax?</p>

<p>Thanks.
<a href="https://i.sstatic.net/QcaK0.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/QcaK0.jpg" alt="Photograph"></a></p>

CC BY-SA 4.0
2020-04-15T20:29:58.917Z
I *really* hate that it feels like I'm beating up on your questions, I promise I'm not. I do, however, feel that these kind of questions are not drone specific. This question in particular isn't framed where we can know for sure that the answer is correct. Any answer is opinion based, and generic opinions about RF are best asked on SE.Electronics. Again, I really apologize if it feels like I'm being overwhelming, and let me know if there's anything I can do to help.
Kenn Sebesta
CC BY-SA 4.0
2020-04-15T20:32:44.040Z
@KennSebesta haha don’t worry about it. Yep, I also agree that this leans very closely to the electronics side of things so was unsure as to whether to post it or not. I figured that I’d post it anyway, mainly to get responses like yours (also, I really don’t want to have to wait for a new coax to arrive haha). It’s important to establish a posting culture in each SE, so I’m glad we’re figuring out what is and isn’t good here.
Drones and Whatnot
CC BY-SA 4.0
2020-04-15T21:01:47.180Z
+1. BTW, you can totally save that with some heat shrink or electrical tape. Or ignore it, it's only the ground shield so considering its location it's effectively as if the connector was a little larger. So long as nothing pulls or pokes to hurt the braid, it will function for another ten years.
Kenn Sebesta
CC BY-SA 4.0
2020-04-15T21:23:57.940Z
Everyone is assuming that the antenna has no gnd plane
tiago ramos
CC BY-SA 4.0
2020-04-15T22:35:25.547Z
To me that photo looks like the shield/ground is completely seperated from the connector, if that is the case, it will sigificantly effect the performance of any antenna you connect to it.
Joshua Marshall
CC BY-SA 4.0
2020-04-15T22:37:52.257Z
@JoshuaMarshall you are correct - I’ve just had a look and seen that, so I’ve bridged the gap with solder and some thin strands of copper wire. Thanks for your advice
Drones and Whatnot
CC BY-SA 4.0
2020-04-15T22:41:20.767Z
@KennSebesta thanks - I’ve bridged the severed braid with solder and thin copper strands. I’ve tested continuity now and it all seems to check out :)
Drones and Whatnot
CC BY-SA 4.0
2020-04-16T02:44:52.143Z
Oh, gosh, I hadn't noticed that the shield was separated from the antenna. If that's the case, any fix needs to be almost equally dense. So if the thin copper strands completely encircle the inner dialectric (the plastic bit under the shield), then you'll be okay. If not, you'll get degraded reception/transmission.
Kenn Sebesta
CC BY-SA 4.0
2020-04-16T03:38:46.453Z
@KennSebesta Yes and no; while dealing with coax and RF is common in far more places than just drones, it's a big part of dronebuilding. As such, I would consider questions about the RF side of things very much drone specific.

Shall we make a Meta discussion on the matter, maybe?
FlashCactus
CC BY-SA 4.0
2020-04-16T06:33:40.827Z
(Created a discussion in Meta. See https://drones.meta.stackexchange.com/questions/55/are-questions-about-drone-related-electrical-engineering-on-topic)
FlashCactus
CC BY-SA 4.0
2020-04-16T09:49:48.767Z
@KennSebesta thanks, that’s good to know. I’ve ordered a new antenna because the copper is really uneven, the main point of me fixing the antenna to any degree is so I can power on my VTX without burning it out. Thanks for your advice.
Drones and Whatnot
CC BY-SA 4.0
2020-04-16T11:06:30.883Z
@DronesandWhatnot While you're waiting for your new antenna, you could just snip off the damaged part of the coax and resolder it to the connector. It's not particularly hard, if you're reasonably good at soldering.
FlashCactus
<hardware><antenna>
How important is the plastic coating around a coax?
Drones and Whatnot
# How important is the plastic coating around a coax?

(Asked by: username_0 on 2020-04-15)

I was swapping over my pigtails and part of the plastic coating around the coax came off.

The coax is still firmly soldered to the SMA connector - is this salvageable with some heat shrink, or do I need a new coax?

Thanks.
[![Photograph](https://i.sstatic.net/QcaK0.jpg)](https://i.sstatic.net/QcaK0.jpg)

**Tags:** hardware, antenna
> **Comments:**
> **username_1**: I *really* hate that it feels like I'm beating up on your questions, I promise I'm not. I do, however, feel that these kind of questions are not drone specific. This question in particular isn't framed where we can know for sure that the answer is correct. Any answer is opinion based, and generic opinions about RF are best asked on SE.Electronics. Again, I really apologize if it feels like I'm being overwhelming, and let me know if there's anything I can do to help.  
> **username_0**: @KennSebesta haha don’t worry about it. Yep, I also agree that this leans very closely to the electronics side of things so was unsure as to whether to post it or not. I figured that I’d post it anyway, mainly to get responses like yours (also, I really don’t want to have to wait for a new coax to arrive haha). It’s important to establish a posting culture in each SE, so I’m glad we’re figuring out what is and isn’t good here.  
> **username_1**: +1. BTW, you can totally save that with some heat shrink or electrical tape. Or ignore it, it's only the ground shield so considering its location it's effectively as if the connector was a little larger. So long as nothing pulls or pokes to hurt the braid, it will function for another ten years.  
> **username_2**: Everyone is assuming that the antenna has no gnd plane  
> **username_3**: To me that photo looks like the shield/ground is completely seperated from the connector, if that is the case, it will sigificantly effect the performance of any antenna you connect to it.  
> **username_0**: @JoshuaMarshall you are correct - I’ve just had a look and seen that, so I’ve bridged the gap with solder and some thin strands of copper wire. Thanks for your advice  
> **username_0**: @KennSebesta thanks - I’ve bridged the severed braid with solder and thin copper strands. I’ve tested continuity now and it all seems to check out :)  
> **username_1**: Oh, gosh, I hadn't noticed that the shield was separated from the antenna. If that's the case, any fix needs to be almost equally dense. So if the thin copper strands completely encircle the inner dialectric (the plastic bit under the shield), then you'll be okay. If not, you'll get degraded reception/transmission.  
> **username_4**: @KennSebesta Yes and no; while dealing with coax and RF is common in far more places than just drones, it's a big part of dronebuilding. As such, I would consider questions about the RF side of things very much drone specific.  Shall we make a Meta discussion on the matter, maybe?  
> **username_4**: (Created a discussion in Meta. See https://drones.meta.stackexchange.com/questions/55/are-questions-about-drone-related-electrical-engineering-on-topic)  
> **username_0**: @KennSebesta thanks, that’s good to know. I’ve ordered a new antenna because the copper is really uneven, the main point of me fixing the antenna to any degree is so I can power on my VTX without burning it out. Thanks for your advice.  
> **username_4**: @DronesandWhatnot While you're waiting for your new antenna, you could just snip off the damaged part of the coax and resolder it to the connector. It's not particularly hard, if you're reasonably good at soldering.  

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## 1 answers

### Answer by username_5 on 2020-04-15. Score: 2 | Accepted answer

The outermost plastic coating is not too critical; this primarily protects the braid from damage or exposure to elements. For the length involved in your image, you should be fine just adding heatshrink to cover that - and if you extend it over the pin you can get some strain relief too.


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