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The reason I left that comment is because determining the quality of a coaxial cable involves electrical engineering more so than an electrician, let alone some DIY. The rule of thumb "would you a...
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#2: Post edited
by
Lundin
·
2023-09-07T06:49:27Z (8 months ago)
- The reason I left that comment is because determining the quality of a coaxial cable involves electrical engineering more so than an electrician, let alone some DIY.
- The rule of thumb "would you ask this to an engineer or electrician" is good. However, in this case you are unlikely to get a good reply from an electrician, since this was actually a RF question.
- There are various obvious things you can check with a multi-meter such as signal and shield contact. But the main concern here is the characteristic impedance of the coax and measuring it is pretty complex. Also it involves a LCR meter, VNA or a similar EE tool which you are unlikely to find outside a professional setting, since they are very expensive. (Decent LCR meters start at $500 somewhere, a VNA typically costs as much as new car.) And then some theory and equations, depending on just how picky you are with finding the exact value or just "close enough".
- Similarly, soldering and assembly of coaxial connectors is quite tricky and definitely not a job for an electrician let alone some DIY. So if you find out that a connector is bad or lacks shield, the only serious option for an electrician/DIY would be to replace the whole cable and buy a new pre-assembled one. (I have personally soldered/assembled my fair share of these but it's in a professional context and with IPC training. RF connectors are some of the trickiest things out there when it comes to hand soldering.)
- What's definitely on-topic here:
- - Determining the characteristics of electrical components in theory and practice.
- - Impedance matching and similar RF design concerns.
- - Design or component level questions regarding VAC mains power supply.
- Soldering and electronics assembly.
- The reason I left that comment is because determining the quality of a coaxial cable involves electrical engineering more so than an electrician, let alone some DIY.
- The rule of thumb "would you ask this to an engineer or electrician" is good. However, in this case you are unlikely to get a good reply from an electrician, since this was actually a RF question.
- There are various obvious things you can check with a multi-meter such as signal and shield contact. But the main concern here is the characteristic impedance of the coax and measuring it is pretty complex. Also it involves a LCR meter, VNA or a similar EE tool which you are unlikely to find outside a professional setting, since they are very expensive. (Decent LCR meters start at $500 somewhere, a VNA typically costs as much as new car.) And then some theory and equations, depending on just how picky you are with finding the exact value or just "close enough".
- Similarly, soldering and assembly of coaxial connectors is quite tricky and definitely not a job for an electrician let alone some DIY. So if you find out that a connector is bad or lacks shield, the only serious option for an electrician/DIY would be to replace the whole cable and buy a new pre-assembled one. (I have personally soldered/assembled my fair share of these but it's in a professional context and with IPC training. RF connectors are some of the trickiest things out there when it comes to hand soldering.)
- What's definitely on-topic here:
- - Determining the characteristics of electrical components in theory and practice.
- - Impedance matching and similar RF design concerns.
- - Design or component level questions regarding VAC mains power supply.
- - Soldering and electronics assembly.
- But to summarize, I think the question would be fine on either site and we can tolerate having a scope overlap, and refer people to one site or the other, when a question might get a better reply elsewhere.
#1: Initial revision
by
Lundin
·
2023-09-07T06:46:53Z (8 months ago)
The reason I left that comment is because determining the quality of a coaxial cable involves electrical engineering more so than an electrician, let alone some DIY. The rule of thumb "would you ask this to an engineer or electrician" is good. However, in this case you are unlikely to get a good reply from an electrician, since this was actually a RF question. There are various obvious things you can check with a multi-meter such as signal and shield contact. But the main concern here is the characteristic impedance of the coax and measuring it is pretty complex. Also it involves a LCR meter, VNA or a similar EE tool which you are unlikely to find outside a professional setting, since they are very expensive. (Decent LCR meters start at $500 somewhere, a VNA typically costs as much as new car.) And then some theory and equations, depending on just how picky you are with finding the exact value or just "close enough". Similarly, soldering and assembly of coaxial connectors is quite tricky and definitely not a job for an electrician let alone some DIY. So if you find out that a connector is bad or lacks shield, the only serious option for an electrician/DIY would be to replace the whole cable and buy a new pre-assembled one. (I have personally soldered/assembled my fair share of these but it's in a professional context and with IPC training. RF connectors are some of the trickiest things out there when it comes to hand soldering.) What's definitely on-topic here: - Determining the characteristics of electrical components in theory and practice. - Impedance matching and similar RF design concerns. - Design or component level questions regarding VAC mains power supply. - Soldering and electronics assembly.