Mr - Fix Tech Repairs

21/12/2022

How do Smart Watches measure the Heartbeat on the wrist?

The heart rate monitor is based on a difficult to pronounce technology called photoplethysmography, but it basically comes down to using green LED lights paired with light‑sensitive photodiodes to illuminate your skin and measures changes in light absorption.
This lets the device detect the amount of blood flowing through your wrist at any given moment. Because blood is red, it reflects red light and absorbs green light.
“When your heart beats, the blood flow in your wrist — and the green light absorption — is greater. Between beats, it’s less,” reads the document.
The sensor are designed to compensate for low signal levels by increasing both LED brightness and sampling rate. That’s why the heart rate sensor on the back of the device flashes its LED lights hundreds of times per second, helping the device calculate heart rates precisely.
But when it measures your heart rate every ten minutes, the Watch switches to using infrared light and if it fails to provide an adequate reading while using the infrared light, the device switches back to the green LEDs.
In order for the sensor to work as advertised, the Watch must be close to your skin. The company advises tightening the band in case the sensors aren’t reading your heart rate accurately.

18/12/2022

Why do people use Bug to describe Loophole in Computer OS or Programs?

An error, flaw, or fault in any computer software or hardware system. It results in unexpected and unwanted results, causing the system to behave weirdly. Put simply, and it is any fault in the computer system that keeps it from performing what it is intended to do.
Most bugs take place because of mistakes caused by developers while creating the code or the design. There could be errors in the components or operating systems used by the program in question.
Some bugs could result from errors in translation between languages, resulting in illegible or incorrect code. It can be a subtle bug or can result in a system crash or freezing. Some bugs can cause security issues and enable malicious users to obtain unauthorized access to your system.
The term "Computer Bug" may be a relatively new word. But it has been used in the formal engineering world for quite a long time. The concept might date back to 1843 when Ada Lovelace, a UK-based English mathematician, and writer, referred to problematic program cards in the analytical engine of Charles Babbage. Lovelace spoke about wrong orders performed by the analytical engine, referred to as cards, not bugs.
The first recorded use of the word “bug comes from Thomas Edison. In a letter he wrote in 1878 to an associated, he wrote, “I find a bug in my apparatus of telephones.”
In November of the same year, Edison wrote to Theodore Puskas, “This thing gives out bugs – as such little faults are called.”
But the late, great Isaac Asimov is probably the one who made the term "bug" popular in the general public. He used the word in 1944 to refer to issues with a robot. The American writer and professor wrote, “U.S. robots had got plenty of bugs out of multiple robots used for field-testing.

Reportedly, it is said that the first usage of the word “bug” for computers was recorded on September 9, 1947. Interestingly, it was a real-life moth preserved behind an adhesive tape on the logbook of machines.
On the same day, a leading computer engineer, Grace Hopper, found an error on the Mark II to a dead moth. He carefully removed and taped the inspect to the logbook.
The term computer bug was used to describe that particular event. While Harvard Mark II operators did not introduce the term 'bug,' the incident certainly contributed to its popularity.
As a result, the word “bug” became a generally used term to describe any glitches or errors in a computer program.

16/12/2022

How do Radio Pagers work?

A pager is a small telecommunication device that receives signals from the paging network. in two way pagers, radio signals are sent from the device as well. The paging network broadcasts signals over a specific frequency, pagers that are in the physical range of the transmitters listen to the signal from the transmitter. Pagers have unique addresses.
There are two type of paging networks broadly classified by range - On Site Paging Network and Wide Area Paging Networks. The on site systems use low and high power transmitters to send messages locally or in house, this is popularly used in hospitals and restaurants for in-staff communications. Wide Area paging networks rely on high-powered transmission across the country, this is used by the public services department, like the armed forces and the fire department.

One wonders in 2022 with the widespread availability of the internet and cellular networks are paging networks still relevant? The reason for this lies in the paging networks reliability over cellular networks, as they use high frequency radio signals with antennas that are typically located high off the ground, so they can extend their reach much more with fewer transmitters and far less interference.
Physical obstacles such as thick concrete walls as well as basement locations make cellular network a non viable option while paging networks work seamlessly. Paging networks also employ multiple towers simultaneously providing more reliable coverage.
Modern paging networks also incorporate satellites connecting the core messaging network and the transmitting towers bypassing vulnerable telephone and Radio Frequency link networks providing higher degree of security and efficiency in communication.

15/12/2022

How does Debit card processing work?

When the payment is initiated by the customer swiping Debit Card on POS device or entering Cards details such as Card Number, Expiry Date, CVV on App or website.
From this exchange, your point-of-sale system (POS system) reads the card information and transmits the data to the customer’s card processing network (Visa, MasterCard, etc.).
The processing network verifies the data and evaluates it for the possibility of fraud.
The processing network then sends the data to the issuing bank (i.e. the bank that issued the customer’s debit card).
The issuing bank confirms that enough funds are available and passes along an approval to the merchant or business owner.
Although this process may seem complicated, it occurs in only seconds — making debit cards (and credit cards) a very efficient form of payment.
The types of debit card processing are categorized by the way the card interacts with your POS system, and therefore, the way the data is transmitted and validated.
i.e.
PIN Debit Transactions
Signature Debit Transactions
Contactless Debit Transactions

28/11/2022

How do QR codes work?

QR codes are a technology that desperately wants our attention. They appear everywhere from supermarket shelves and magazines to hiking trails and tombstones.
QR (Quick Response) code is the trademark name for the two dimensional barcode system. It was originally invented in 1994 by Denso Wave, a Toyota subsidiary, as a way to track vehicles as they were assembled, and to scan components at high speeds. While Denso Wave does hold the patent on the technology, it has granted free licence on it, going so far as to publish the spec online, and allowing anyone to use it.
The conventional one dimensional barcodes used on virtually every consumer product are mechanically scanned. That is, they're read by physically bouncing a narrow beam of light onto the code, which can be interpreted using the pattern of light reflected off the white gaps between the lines.
A QR code works by encoding data in a certain way (a certain standard) so scanning software can interpret the results. For example, normal barcodes on products are considered 1D barcodes. The lines are different widths that correspond to numbers. Software interprets those line widths as numbers.
Same with the QR code; the location of each block is interpreted by the software and the combination of a bunch of blocks combine to represent certain characters. Combine the characters and you can get a URL for example.
If you add logic in the scanning software that opens a browser and goes to the link when the encoded data looks like a URL (with http://), you have added the functionality of translating printed material into digital material.

05/11/2022

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If available, order your Vuma Reach Service and complete your order

03/11/2022

We also help you with your gaming controllers.

22/10/2022

22/10/2022

Samsung A20 for R1299

13/08/2022

Thats true!