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Saturday, November 28, 2020

Manually install an SSL certificate on my cPanel hosting

 Manually install an SSL certificate on my cPanel hosting.

After your certificate request is approved, you can download your certificate from the SSL manager and install it on your cPanel hosting account. You can watch a short video of this task farther down the page.

Required: Deluxe and extended validation (EV) certificates, as well as SSLs for addon domains or subdomains must be installed manually.

If you haven't done it already, download your certificate from the SSL manager and save the .crt file somewhere that's easy to find.

Go to your Hosting cPanel product page.

Select Web Hosting and then select Manage for the cPanel account you're installing the SSL on.

Select cPanel Admin.

In the Security section, select SSL/TLS.

Under Certificates (CRT), select Generate, view, upload, or delete SSL certificates.

In the Upload a New Certificate section, select Choose File and navigate to the .crt file you downloaded in step 1. Select the file and then select Open.

If you want to, type a description of the certificate in the Description text box.

Select Upload Certificate.

When you get confirmation that the certificate has been saved, select Go Back.

At the bottom of the SSL Certificates page, select Return to SSL Manager.

Under Install and Manage SSL for your site (HTTPS), select Manage SSL Sites.

In the Install an SSL Website section, select Browse Certificates.

Select the certificate that you want to activate and select Use Certificate. This will auto-fill the fields for the certificate.

At the bottom of the page, select Install Certificate.

On the Successfully Installed pop up, select OK.

Your certificate is installed! Now you need to direct visitors to the secure version of your site by redirecting to HTTPS.

Manually install an SSL certificate on my cPanel hosting.

Friday, November 13, 2020

What is the difference between PAL, NTSC, SECAM? What are the World Wide TV Standards? Difference between Pal vs NTSC?


There are a number of TV Standards worldwide. Not all television sets in the world are alike. Countries use one of the three main video standards – PAL, NTSC or SECAM. What this means is that a video from a PAL country will not play in a country that uses the NTSC standard.


Before we dive deep into the various TV Standards we shall take a look at a few basics of TV transmission. A television transmission consists of a set of rapidly changing pictures to provide an illusion of continuous moving picture to the viewer. The pictures need to come at a rate of 20 pictures per second to create this illusion. Each of these "rapidly changing" pictures is a frame. A typical TV transmission is at 25-30 frames per second (fps).



Each frame consists of several closely spaced lines. The lines are scanned from left to right and from top to left. A typical TV picture consists of 525 to 625 lines. Considering this large number of lines, if all were to be written one after another the picture would begin to fade at the top by the time the last line is written. To avoid this, the first frame carries the odd numbered lines and the next frame carries the even numbered lines. This provides uniformity in the picture and this is called interlacing.



TV receivers require a source to time the rapid succession of frames on the screen. Designers decided to use the Mains power supply frequency as this source for two good reasons. The first was that with the older type of power supply, you would get rolling hum bars on the TV picture if the mains supply and power source were not at exactly the same frequency. The second was that the TV studio lights or for that matter all fluorescent, non incandescent lights flicker at the mains frequency. Since this flicker is much higher than 16 times per second the eye does not detect it. However this flicker could evolve into an extremely pronounced low frequency flicker on TV screens due to a "beat" frequency generated between the light flicker and the mains frequency. This would have made programmes un-viewable particularly in the early days of development of TV receivers.

The two mains power frequencies worldwide are 50Hz and 60Hz. This meant that there was an immediate division in the TV standards - the one with 25 frames per second (50 Hz) and 30 frames per second (60 Hz). Most of the compatibility problems between TV standards across the world stem from this basic difference in frequencies.

NTSC (National Television Standards Committee)

The majority of 60Hz based countries use a technique known as NTSC originally developed in the United States by a focus committee called the National Television Standards Committee. NTSC (often funnily referred to as Never Twice the Same Colour) works perfectly in a video or closed circuit environment but can exhibit problems of varying colour when used in a broadcast environment.

PAL (Phase Alternate Lines)

This hue change problem is caused by shifts in the colour sub-carrier phase of the signal. A modified version of NTSC soon appeared which differed mainly in that the sub-carrier phase was reversed on each second line; this is known as PAL, standing for Phase Alternate Lines (it has a wide range of funny acronyms including Pictures At Last, Pay for Added Luxury etc). PAL has been adopted by a few 60Hz countries, most notably Brazil.


Amongst the countries based on 50Hz systems, PAL has been the most widely adopted. PAL is not the only colour system in widespread use with 50Hz; the French designed a system of their own -primarily for political reasons to protect their domestic manufacturing companies - which is known as SECAM, standing for Sequential Couleur Avec Memoire. The most common facetious acronym is System Essentially Contrary to American Method.


Some Satellite TV transmissions (usually Russian) that are available over India, are in SECAM Since the field (25 frames /sec) and scan rates are identical, a SECAM signal will replay in B&W on a PAL TV and vice versa. However, transmission frequencies and encoding differences make equipment incompatible from a broadcast viewpoint. For the same reason, system converters between PAL and SECAM, while often difficult to find, are reasonably cheap. In Europe, a few Direct Satellite Broadcasting services use a system called D-MAC. Its use is not wide-spread at present and it is trans-coded to PAL or SECAM to permit video recording of its signals. It includes features for 16:9 (widescreen) aspect ratio transmissions and an eventual migration path to Europe's proposed HDTV standard. There are other MAC-based standards in use around the world including B-MAC in Australia and B-MAC60 on some private networks in the USA. There is also a second European variant called D2-MAC which supports additional audio channels making transmitted signals incompatible, but not baseband signals.

Quick Facts:

  • NTSC and PAL are video standards that are recorded on the cassette. These videos send and electronic signal to the television, then only it can be viewed.
  • In, India, PAL video format is supported.
  • NTSC is the video standard commonly used in North America and most of South America.
  • PAL is the video standard which is popular in most of the European and Asian countries.
  • The difference between NTSC and PAL is the transmission of number of frames per second. In NTSC, 30 frames are transmitted per second. Each frame is constituted up of 525 scan lines.
  • In PAL, 25 frames are transmitted per second. Each frame consists of 625 scan lines.
  • Second, the power frequency used in NTSC is 60 Hz. While in PAL, the power frequency is 50 HZ.

Suggested Readings

[1].From World TV Standards (http://www.scatmag.com/technical/worldtv.pdf)