Active and Passive Cables

In this video from ITFreeTraining, I will look at Active and Passive cables. What you are trying to achieve will determine which cable you will use. When purchasing cables, it is important to understand what you are buying, so it will achieve the results that you want.
Download the PDF handout: itfreetraining.com/handouts/ap...
Passive Cables
0:15 To start with, I will look at passive cables. A passive cable is essentially a cable with no additional electronics or very minimal cheap electronics. Since there is not much in the cable, the cable is cheaper to make, however a cheaper cable is not without its problems.
Shown here is a five-meter USB passive cable. This cable is very cheap but also very unreliable. When I tested this cable, I could get it to work with low speed devices, however USB 2 devices would sometimes work and at other times would not work at all. At the end of the day, you get what you pay for. You will generally find that passive cables work better when they are short, but the longer they get the more unreliable they become.
Due to the cable being a passive cable, the device it is connected to needs to power the cable, which can lead to more data being lost over longer distances. Essentially, think of it like a water hose; if you switch the hose on, you require more pressure to get the water to go further. Cables work the same way, the longer you make the cable, the more power you need to push the signal through the cable.
Electrical signals are affected by interference. Interference will affect the signal and thus cause data loss. Interference can come from many sources. The source can include the cable itself. If you start putting more power through the cable, the cable itself will generate more interference from magnetic fields the cable creates. This interference can affect the cable itself and other cables that may be near it. So, you can see the answer is not to simply up the power. Let’s look at how active cables eliminate some of these problems.
Active Cables
2:07 An active cable uses embedded circuits to recreate the signal. Shown here is an active five-meter USB cable. You can see on the left-hand side of the cable there is a large plastic casing attached to the cable. This contains the circuits which makes the cable an active cable. In a moment I will have a look at the circuits that are inside. Some cables will not be as obvious as this one. With some cables the electronics will be inside the plug; I will have a look at such a cable later in the video.
An active cable can increase the possible maximum length of the cable. For example, you will find that, with an active cable, the length may be increased to be even longer than the maximum specification allows. If you need to purchase a cable longer than the maximum specification allows, make sure it is an active cable. In some cases, you may not be able to get a cable long enough to meet your needs; however, you may be able to combine multiple active cables together to get a longer length. Each cable will recreate the signal, but you won’t be able to use passive cables as they do not recreate the signal. Generally, the manufacturer of the active cable will include (with their specification of the cable) how many cables can be connected together.
The disadvantage of active cables is that they cost more; however, they work really well compared to passive cables. For example, this five-meter cable works flawlessly compared with the passive five-meter cable I looked at before. If you need a longer cable, consider using an active cable as they work a lot better, even though they do cost more.
In some cases, the active cable may need external power in order to operate. In the case of this cable, no external power is required, as the embedded circuits draw their power from the device it is plugged into to. Keep this in mind, as with some active cables, if the external power is not connected, the cable will essentially become a passive cable and may not work at all.
One of the criticisms of active cables is that some of these cables contain additional security features. For example, this may limit what devices can be used with the cable. Although the primary purpose of an active cable is to increase the reliability of the cable, its circuitry can be used for other things. Let’s have a look inside this cable so we can better understand how it works.
Description to long for CZcams. Please see the following link for the rest of the description. itfreetraining.com/ap/1c70
References
“Active cable” en.wikipedia.org/wiki/Active_...
Credits
Trainer: Austin Mason ITFreeTraining.com
Voice Talent: HP Lewis hplewis.com
Quality Assurance: Brett Batson www.pbb-proofreading.uk

[@j283]

The VGA splitter at 7:00 is actually a DVI splitter.

[@derkaderkamohamadallaackbarnut]

Nice simple explanation. Good job.

[@itfreetraining]

Glad it was helpful!

[@edwinjonah]

Thanks a lot! This helped me understand these concepts.

[@itfreetraining]

Thanks for watching.

[@13serhio]

Thank you for the video. I agree about the length of the cable, the shorter the better.

[@itfreetraining]

Glad it was helpful!

[@tompenny5906]

Thank you so much for your videos.

[@itfreetraining]

Glad you like them!

[@tablatronix]

I have not been able to find any information about passive serial to usb cables, these were used in the early usb 1 days I believe and I cant find any information on how to do it..

[@itfreetraining]

This video I believe covers what you are talking about.
czcams.com/video/O1MhwPb2NWA/video.html