125
votes
Accepted
Why isn't stripping wires by burning with a lighter a more common practice?
It stinks
It leaves soot and partially burned plastic on the wire and between the strands - those makes solder joints more difficult to make and less reliable.
It is difficult to control how far back ...
- 69.2k
100
votes
Accepted
Why are copper cables round?
Like Jessica Rabbit- because they are drawn that way.
Wire production involves pulling (drawing) the wire through successively smaller dies (often with annealing in between). The dies are most ...
- 384k
75
votes
Why isn't stripping wires by burning with a lighter a more common practice?
We old farts mainly do it to show off our skills to young whipsnappers. Few things are as satisfactory to see a student or new employee ogle at how, with just some side cutters, you quickly remove the ...
- 14.2k
64
votes
Accepted
What are those weird wires in the audio cables?
Those are normal headphone wires.
The colored strands are copper insulated in a colored lacquer.
The core of each wire is a string (for strength as copper wire is not all that strong - especially not ...
- 69.2k
53
votes
Why is an Ethernet cable not grounded?
If you just ignore the POE 48 Volts in the image below, you can see Ethernet uses transformers on both sides.
This way there is no need for common ground as long as the common mode voltage stays ...
- 22.3k
48
votes
Accepted
Can a premium HDMI cable outperform a standard cable?
You would do a BERT (bit error rate test) on the cable. Better yet, look at the eye diagram at the far end of the cable.
HDMI is a digital format, which means that there's a threshold effect — ...
- 171k
45
votes
Why are copper cables round?
When you move away from circular cross sections you run into two significant problems:
First, corners would exert more pressure against adjacent things, and are more likely to result in insulation ...
- 20.4k
45
votes
Accepted
Is there a low-cost alternative to RJ45 cables for large number of signals?
There are ribbon cables with twisted wires:
Every few cm, there is a flat section to allow attaching an IDC connector.
Looking at two product drawings it appears to be pretty typical to have 50 mm ...
- 128k
45
votes
Accepted
Why is USB Type-A to USB Type-A never used?
USB-A male to USB-A female is fine. They exist, and are relatively common. They work just fine as USB extension cables, provided the overall length is not too long. For longer distances, active ...
- 40.8k
45
votes
Accepted
Why does the current carrying capability of a cable increase with temperature
You're looking at it from the wrong direction.
The more current you put through a cable, the hotter it gets. Push too much current through, and the insulation starts to deteriorate. Wire insulation, ...
- 19k
42
votes
Accepted
Can I use I2C over 2m cables?
I2C is not designed to be used over long distances but I know of several applications where it is actually used over a distance of about 2 meters.
I also know of one case where they had issues with ...
- 3,151
39
votes
Accepted
Why is it dangerous use a coiled extension cord?
The normal cable ratings assume that the wire can adequately disperse heat generated in the cable due to the current flowing.
If you coil it up and use close to the maximum rating then it stands a ...
- 32.6k
36
votes
Why is an Ethernet cable not grounded?
Why is Ethernet not grounded? There are two reasons:
It would create a ground loop between devices
The device would also be more susceptible to ESD which is prevalent in cables that are being moved ...
- 78.1k
35
votes
Why are copper cables round?
Flexibility
A round cross section allows the wire to flex in any direction equally.
- 11.9k
34
votes
Accepted
Wiring diagram for USB-C to USB-A cable?
The USB 3.1 specification spells out exactly how to make this, and any other USB C -to- USB legacy cable. For a USB-A (2.0), the connection looks like:
- 1,601
34
votes
Accepted
why is there dark fiber?
Dark fiber (unused fiberoptic cables) is a confusing term for me. Why would any company build so much excess capacity?
The marginal cost of adding one more fiber when digging up a street is very, ...
- 16.1k
33
votes
Accepted
Is it bad practice to parallel power connector contacts?
Using parallel pins of a connector or parallel wires in a cable to increase the current capability is standard practice. It has been done for a very long time, probably since the start of electrical ...
- 22.2k
32
votes
Accepted
Pass USB 3.0 connection through D-SUB connector
I assume this is due to insufficient shielding to get a USB 3.0 link?
It's more likely that you simply introduce an impedance break so significant by separating the conductor pairs of the superspeed ...
- 90.8k
30
votes
Accepted
What is this 3.5mm plug designed for?
The ends of wires in a cable get soldered to the left end of that assembly. Then the assembly is placed into a mold and hot plastic is injected around the wire to form a handle for the end of the ...
- 57k
30
votes
Why isn't stripping wires by burning with a lighter a more common practice?
Because using the correct tool gives you a better result with precise strip lengths without the risk of leaving combustion products all over the wire which will adversely effect solder-ability or ...
- 8,515
27
votes
Can a premium HDMI cable outperform a standard cable?
HDMI cables are tested at an Authorized Testing Center (ATC) and given a certification based on how much bandwidth they can handle (which is to say, how high of a frequency signal they can transmit ...
- 370
27
votes
Accepted
Are there any advantages to using rigid RF coaxial cables?
So, are there any advantages to using rigid RF coaxial cables?
First, the product you show might be semi-rigid rather than rigid cable.
In either case, the main advantage is lower loss, because of ...
- 128k
27
votes
Accepted
Is there a minimum length for SATA cables?
I have designed SATA asic serdes circuits and do not recall issues with short cables.
However, we do test for very long and very short length test cases to ensure sufficient signal integrity at either ...
- 3,117
26
votes
What makes a high speed USB cable high speed?
USB is defined at several data rates.
12 Mbps is called "Full Speed"
480 Mbps is called "High Speed"
5 Gbps is called "SuperSpeed"
10 Gbps is called "SuperSpeed+"
A USB product marketed as "High ...
- 128k
25
votes
Wiring a 240 V single phase cable to two 110 V outlets (120 deg apart)
Do not do this. Full stop. It's not safe, and it shouldn't be necessary. You can always use a step-up transformer, if the load is 2kVA or less. Otherwise, pull a 208V circuit from the panel. Since ...
24
votes
Why is it dangerous use a coiled extension cord?
Here's another illustration.
Used to charge an EV at 'only' 10A... MW
- 249
22
votes
Why isn't stripping wires by burning with a lighter a more common practice?
Whether it produces good results or not, wire insulation is one of the worse things to set on fire because "modern electric wires commonly use PVC plasticized with linear Phthalates" as insulation1. ...
22
votes
Accepted
Orange unshielded coaxial cable
Technically, if it doesn't have a shield, it's not a coax cable, or wire.
That aside, it may be a tracer wire (not sure if this is the proper name or not).
Utilities bury these alongside non-metallic ...
- 10.3k
21
votes
When wiring a European (Schuko) plug, what thing should I focus on not to mess up?
I assume the plug uses screw terminals. In this case, and if you use stranded wires, use wire ferrules to protect the wire strands from breaking.
The wire must be rated for 16A usually.
Ensure that ...
- 461
21
votes
Accepted
Is it necessary to separate DC power cables and data cables?
The answer is "It all depends".
What is the load on the DC? If it's very noisy inductive loads, you're going to have noise on the DC line, and it might be considerably more than you'd think
What is ...
- 13.2k
Only top scored, non community-wiki answers of a minimum length are eligible