Wednesday, December 21, 2022

Random thought - Antenna Impedance

 I've been attempting (since the 2020 lockdown in fact) to get back on the radio-waves. Somehow something always keeps me from making the last mile. At this point of time, it is the Antenna. Living out of a suitcase from one room in the ground floor - I can not put up a suitable antenna. 

The paragraph above makes it appear that an antenna is a complicated affair; it isn't. At the same time it is important to specify that 'antenna' really means 'antenna system'. This means there are multiple participants in an antenna system. Ensuring these participants perform in lock-step makes the difference between hearing a radio station, and not. One of these things is something called antenna impedance. Traditionally, radio transmitters have an impedance of 50 ohms. For a signal to be transmitted effectively & efficiently, the antenna system too must exhibi the same impedance. 

A good example would be ,marrying a hose-pipe with a well-pump. If the hose-pipe is not of adequate diameter, the joint may not survive the pumping operation. If the hose-pipe is too broad, the water it transports may not reach the destination. So it is important the antenna system impedance match the impedance of the transmitter. This matching action is done by devices such as Transmission Line Transformer, Antenna Tuner so on...

But here's the bit, the antenna impedance is measured between the centre-point, and ground. Now since the impedance is akin to resistance (but more complex as it includes reactance), it may be worked the same way as resistance. Impedance may be put in series, and parallel to arrive at differing values. So it comes about that instead of a TLT, can an antenna be matched by placing a resistor of suitable value in parallel at the feed-point of the radiating element? Think.... Think ...

Wednesday, November 10, 2021

Climate Change: Plant less trees!!

Two things in life are unavoidable – death, and taxes. Well, now there is this third – Climate Change, or Global Warming as it is popularly depicted in media. This globe, what we call ‘Earth’, is older than all of us; at 4.5 Billion years of age it is also, apparently, suffering on account of human activities. Its grown warmer since the Industrial Revolution – and accelerated since after the second world war. Everyone knows it – Climate change is even on the lips of babes & sucklings. The cause, if you follow popular media, is us – humans. There are detractors. Heretics who put forth a counter-current that climate change is natural rather than anthropogenic. That greenhouse gases (yes, it isn’t only Carbon Dioxide) are not affected by human activities to the extent presented. Water vapour is a culprit just as much as are Methane, Nitrous Oxide, and Ozone. That human species came into existence on Earth at a time when climate on Earth was ramped up to change. Anthropogenic influence can’t be denied though. CFC, PFC are well recognised greenhouse gases.

Like a guilt trip, the anthropogenic argument of climate change, receives more media coverage than detractor arguments from more rational minds. On a daily basis, there will be any number of articles with headlines such as ...

  1. https://www.bbc.com/news/science-environment-58883234

    (Climate change: 'Adapt or die' warning from Environment Agency)

  2. https://www.houstonchronicle.com/business/energy/article/oil-gas-environment-climate-change-goals-why-now-16532566.php

    (Oil companies begin setting environmental goals amid scrutiny over climate change)

  3. https://timesofindia.indiatimes.com/city/kolkata/mass-fruit-tree-plantation-drive-begins-in-west-bengal/articleshow/86683823.cms

    (Mass fruit tree plantation drive begins in West Bengal)

  4. https://theconversation.com/mass-tree-planting-how-to-do-it-right-168583

    (Mass tree planting: how to do it right)

The bottom line is that it is impossible to escape the frenzy around environment. The impression one gets from such articles is of the proverbial doe caught in the headlights of a speeding train. The difference here is that the human species apparently invented the vehicle in whose headlights it is the proverbial doe. The jury is yet out upon whether or not Climate Change is anthropogenic. Regardless of the cause, the fact of the matter is that Climate Change is quite real. The ocean levels are changing, glaciers melting, wind and rainfall patterns changing ... Every single being on Earth is affected. It follows therefore that every single being – capable of it – must take necessary actions to mitigate the effects thereof.

It isn’t as though there haven’t been concerted effects to deal with changing climate on a relatively large scale successfully in the past. London was famous for it’s ‘Pea Soup’ smog as recently as the 1960s. It also dealt with the problem effectively using a multi-pronged approach – regulating vehicle exhaust, factories, household chemicals, and so on. It wasn’t just London that was affected; large cities around the world were part of a study conducted by Manchester University. The results were apalling. From Bangkok, to London, to Mexico, and to Tokyo – poor quality of air plagued the cities.

How does a person, such a tiny entity compared to the gigantic volume of this Earth, attempt to mitigate the effects of Climate Change? To no small extent, the way to do it is to enlist support against the accumulation of greenhouse gases in the atmosphere. There are any number of techniques available legislative, technological, direct action. Here are just a few

  1. Unplug electrically powered devices when you are not using them.

  2. Address the insulation of your home to prevent heat/cold from escaping.

  3. Don’t waste food; if possible purchase from the nearest producers.

  4. Use public transport whenever you can .

The simplest perhaps way you can contribute in battling climate change lies in the tumultuous refrain – plant a tree!

Every tree is an entire ecosystem in itself. From nitrogen fixing bacteria, to providing nectar to bees & fruits thereafter, shelter/succour for residents of the forests – a tree is easily ignored without realising what fantastic service is provided by it in return. Botanists wax eloquently on the properties of varieties of trees. Planting a tree is perhaps the chosen way most contribute towards tackling climate change if only because well, one can put a sapling in the soil, and forget about it for days on end. Water the sapling once in a while, and all will be well. Why trees, though? Because trees are adept at capturing CO2 from the environment, and sequestering it – all the while converting it into wood! The thumb rule is to choose fast growing species ... which is more easily said than done.

Botany is a well established science with an enormous repertoire of literature. At the same time, it goes without saying that growth of any organism – tree or otherwise is not monocausal. Any number of factors are involved; in case of trees some of these factors may be type of soil, nutrients in soil, availability of water, intranecine competition so on. Availability of open spaces, and sunlight are obvious local climate factors that affect growth. This makes it necessary to thin plantations out by trimming, or cutting trees at regular intervals. Plantation must also attempt adequate bio-diversity is maintained. On the one hand this is to prevent the development of an invasive species that affects local flora, and fauna. On the other hand it is to protect the plantation from becoming easy prey to a pest that may decimate the entire plantation.

All this makes it obvious that planting trees is easier said than done. The situation may appear hopeless. Yet all is not lost. It is a matter of record that the vegetables on our dining plates are significantly different from their cousins in the wild. The carrot was pale and yellowish and unpalatable too – now it is orange, white, or even red and delicious to boot! The modern banana is far removed from it’s wild cousin – full of seeds, and a dwarf compared to the banana we know. Pineapples, peaches and many others are almost unrecognisable compared against their wild predecessors. The journey of these modern foods from their wild predecessors was achieved by simple natural selection of the properties that were most desirable ... and took generations to get fixed indelibly in the plants.

It is the quality/quantity argument. A cluster of a few trees of different species could provide the same climate-control effect as a forest. No less important is biovariance. An orchard of a single species is akin to a sponge whereas a jungle of multiple species also serves as a natural obstacle course for pests.

Modern Science, and Technology have made it possible to achieve in short order what took many generations to achieve by means of natural selection. By editing the genes of a species, it is possible to imbue a tree with properties that would appear miraculous. Perhaps then, it should be possible to genetically modify plant species to combat global warming with greater efficiency. Perhaps the transpiration / photosynthesis cycles may be edited to last longer. Perhaps the genes may be edited to also accept gases other than CO2 or even a greater quantity of CO2. The possibilities are limited only by technology itself, and human imagination!

Genetically modified plants (and plant products) are not a novelty. Any number of plant-sourced foods are modified genetically over and above natural selection through the ages. Soyabean, Eggplant, Papaya to name just a few. Applying similar science/es to combat skyrocketing greenhouse gases is a necessity that must be placed on the table.

Thursday, May 12, 2016

From a bleeding heart ...

"Chief Justice of India breaks down before PM - asks for appointment of more judges" This headline almost made me cry.

When a highly disciplined, cultured, qualified individual involved in a brain-intensive profession sheds tears at a public forum - it is a sign things may be at maximum stretch. But imagine all those who choose to carry the burden of the nation for decade after decade without so much as a sign of such pressure they have to endure. For decades now, since the Republic of India came into existence they have stoically borne the burden of responsibility - and yet all the polity has offered are brickbats ... and worse!!

You may, by now, have guessed who I have in mind. I speak, of course, of our poor overburdened legislators.

In 1948 - the draft constitution envisaged 525 seats in the Lok Sabha - with an upper limit of 552 seats. Article 81(1)(b) provided that the States shall be divided, grouped or formed into territorial constituencies and the number of members to be allotted to each such constituency shall be so determined as to ensure that there shall be not less than one member for every 750,000 of the population and not more than one member for every 500,000 of the population.

So ... Minimum of 500,000 (5 Lakh) to be represented by an MP - and maximum of 750000 (7.5 Lakh) But then in 1952, for good & valid reason, the second amendment to the Indian constitution increased the stress on our legislators by removing the upper limit of 750000.

Instead of appreciating the sacrifices legislators make for the general public by accepting the responsibility for so many lakhs of people - the Indian population has chosen to increase the stress our legislators suffer by reproducing in an irresponsible fashion! An action that can only be deemed as ungrateful and apathetic!! To make things worse - the electorate at large have (or appear to have) limited their participation in governance of the nation to exercising their franchise in elections. After the elections the poor legislators are placed under the undue stress of having to *guess* what their constituents opinion/s are - this when constituents could/should have participated actively in voicing their opinion to their legislator/s. Surely we the electorate are irresponsible in placing our legislators in such stressful situations?

Consider that they (our legislators) get an office allowance of Rs 45,000 per month. This includes Rs. 28,000 for staff costs, and the balance to cover costs associated with running their office. This, combined with some support from the Parliament library, are the only resources they have to scrutinise the work and proposals of ministers who have the entire bureaucratic machinery of the government at their disposal.

Rs. 45000 per month as office-expenditure sounds like an enormous amount of money - but is it really such a large amount? Here is a simple discussion

As per the 2011 census, there are 545 Constituencies representing 1210193422 people. Approximately 2220538 (22 Lakh)  citizens are represented by 1 MP!

To put this figure into perspective - here is a very very rough calculation

There are 525600 (365*24*60) minutes in 1 year.

Let us put aside weekends - so reduce the count by (52*24*60) 74880.

Now there are only 450720 minutes available to the MP. Further we would like our MP to have some sleep - so, say, 5 hours of sleep daily + 2 hours of personal time on weekdays ... the count is further reduced by (365-52 *7*60) 131460

Now an MP has 319260 minutes available in 1 year. But the MP must spend some time in parliament - when he is probably away from his constituency. Say we make this count 60 days in a year - 232860 minutes available to his constituents.

The count is actually much less than this because there may be times when the MP is travelling, or out of the constituency for any other reason, or at a party meeting ... so on.

In other words, according to the 2011 census, it is impossible for an MP to meet ALL his constituents if they need his time! Delegation, and quality-support staff are absolutely necessary. Our legislators may not be unjustified in seeking a larger expense/office allowance!

Contrast this with our Indian Army which comprise approximately 20 Lakh people. One soldier stands for 579 citizens!

Compare this with the Police where 1 policeman stands for 761 citizens!

Whilst the good work done by Police, and Army are appreciated - the work done by our legislators goes unappreciated! Our legislators are shamed, dragged to courts ... and worse! One needs only take a look at one of the many newspapers/TV channel to see how poorly our legislators are treated!

Our poor legislators give up their personal lives, they choose to ignore the abuses heaped upon them & their near-and-dear ones by the public-at-large... They choose to construct houses, and roads, and dams, and canals, and airports, and railroads, and police-stations, and hospitals, they choose to step out from their office - and instruct the ignorant electorate on the duty it must fulfil towards the nation, when necessary they choose to stay far away from their loved ones family, friends, and well-wishers - even stay away from India for days on end ... the list is endless. Instead of appreciating the work they do - the electorate at large choose to further add to legislator's stress by continuing to procreate & then blame the lawmakers for "inadequate facilities", "poor quality government", "unresponsive government".

Fellow Citizens, before you contribute your Genes to the growth of the Nation, before you whine about poor governance - hold your peace (pun intended!!) ... spare a moment for all our legislators (Do not be partisan - cut across all party lines) since Independence who have had to bear borne (pardon the pun!) stoically the pain of your pleasures!

Be nice to your legislator - use a condom! 

Thursday, December 18, 2014

... and a time to make a stand

Newspapers, perhaps across the world, carried the news of the carnage carried out at a school in Peshawar. This was punctuated by photographs of grieving families of the deceased.
 

Nobody can imagine a school may be target to an armed assault. Yet, in hindsight, a school serves multiple purposes for that militant mind-set.
 
First - a school is, relatively, an unguarded installation.
Second - children are hardly prepared mentally to recognize the mortal danger.
Third - the large casualties/fatalities would & probably did result in copius attention from the Fourth Estate.
Fourth - most parents, after such an incident, would choose to keep their little ones home rather than risk their lives.
 
The parents who have lost their children have my sympathy. Yet my attention is more with the parents who would attempt to protect their children by keeping them from school.
 
A youngling, as most parents experience, instinctively reacts when his possession is taken away from him. A new-born baby may cry, a slightly older one may throw a tantrum, a school-going child may take a more violent stand - erupt into fisticuffs, throw stones/sticks ... or stronger
 
In the long run a school would teach young minds to stand firm against injustice. It would teach that the law of the land may act slowly but eventually prevails. It would teach impressionable minds that a wrong is righted not by striking back immediately, but by approaching higher authority. A school environment offers a youngling opportunities to develop healthy social interactions, skills (including conflict resolution) in a moderated environment. In the long run social skills developed at school would be more useful in helping end the cycle of violent behaviours. Withdrawing a child from school may make it more likely that child would sooner be on the side of those perpetrators of this incident - therefore more at risk of avoidable injury & life!

To all parents in/around Peshawar (and all such potentially dangerous locations in the world) Children are the future. Education, and knowledge of the world around them is the one thing that can improve their lot in the future. For the sake of your children, do not stop the education of your children because of incidents like this! Stand firm!

Sunday, September 07, 2014

Wanderlust: Making the War-Lord see red!

One issue with habitation of Mars is that it has a thin atmosphere. To paraphrase what this article  states - the thin atmosphere causes problems. These problems vary from an inability to contain water, breathe, and so on. Ergo it is necessary for Mars to have an atmosphere before humans may attempt to habit there.

Earth retains it's atmosphere, in no small part, because of it's magnetic field. In turn the magnetic field is generated by the liquid core deep beneath this planet we call Earth. A magnetic field is necessary for Mars to maintain an atmosphere.

So we were having these thoughts on how to kick-start Mars' magnetic field.

It just struck me (pun intended!) that a rock may be the start of an answer. Our Earth collects anywhere from 5 to 300 tons of space-dust daily to 300 tons of space-dust daily. So why restrict ourselves to a big enough rock? Make it lots & lots of littler (pardon my English!) rocks. So many that the cumulative mass of the planet increases the pressure to the extent the core liquifies again.

Another alternative could be to have an external/artificial magnetic field. Earthlings have already proven themselves capable of sending craft as emissary to meet the War-Lord. Make it several craft instead! Each in an areostationary orbit (emulating the GPS satellites here on Earth), each transmitting over a broad-spectrum omnidirectionally. Voila!

Of course both solutions are easier said than done ... and mutually exclusive. The first, of course, is the issue of motive, and electro-motive power required. But they are available options that may be placed upon the table before they may be discarded (if so!).

Monday, June 09, 2014

Wanderlust: A bum rush!

Solid bodies in the Solar System are relatively few; IMO the inner planets, asteroids, comets, and a few satellites around the Gas Giants. To the best of my knowledge, asteroids & comets lack an atmosphere - and are pock-marked to the extreme.

Out of Mars, Earth, Venus & Mercury - Mercury's atmosphere is ... mercurial, the Venerean atmosphere is lush in the extreme. Mars has a thin atmosphere, whereas Earth's is (for us humans, and a few other species) just right.

Of these 4 terrestrial planets, Earth has the greatest escape velocity at 11.2 km/s followed closely by Venus 10.3km/s, Mars 5km/s, and finally Mercury 4.3km/s.

At it's closest, Venus is around 38 Million km from Earth. Mars is around 54.6 million kilometers in it's turn.

No body is immune to impact by other bodies. Earth too is no stranger to body-play; Micro-micro meteorites accumulate by the giga-ton annually in the form of dust. Larger impact bodies such as the Chicxulub capable of delivering several as much as 100 Teratons equivalent of TNT are also out there - but less frequent. As many as 132 meteorites found on Earth are identified as of Martian origin.

On October 17, 2013, NASA reported, based on analysis of argon in the Martian atmosphere by the Mars Curiosity rover, that certain meteorites found on Earth thought to be from Mars were actually from Mars.


Back in the 1960s/70s, Project Orion was a theoretical study on a nuclear pulse propelled space-ship. Several devices being flung out opposite to the desired direction of thrust. Each device imparting an absurdly humongous specific impulse on detonation.

What I therefore find myself wondering

  1. How large would the impact have been on Mars to impart escape velocity to the rocks that eventually turned up on Earth?
  2. Even given the turbulent environment on Mars, is there a possibility one of the impact craters - the source of an eventual martian meteorite, may be discovered by one of the missions presently on/under-way to Mars?
  3. Is there a probability of discovering a Venerean meteorite here on Earth?
  4. Could Chicxulub, or a comparable impact may have dislodged a rock and sent it to Mars, or Venus?

 

Sunday, June 08, 2014

Wanderlust: Kayoed

The Solar System is comprised of the Sun, Jupiter, and other debris of creation. A portion of the debris are called planets; these are broadly classified as Gas Giants (Jupiter Saturn Uranus & Neptune ), and Terrestrials  (Mercury, Venus, Earth, Mars).

A planet usually has reasonably well-defined orbit. Smaller bodies have a well-defined orbit too, but are more liable to suffer perturbation from larger bodies. These smaller bodies are either comets, or asteroids.

Wikipedia has a great article on meteorites This article defines a meteorite as below

A meteorite is a solid piece of debris, from such sources as asteroids or comets, that originates in outer space and survives its impact with the Earth's surface.

But there are also the rare meteorites that may have originated on Mars. The wikipedia  article on Martian meteorite writes to say

On October 17, 2013, NASA reported, based on analysis of argon in the Martian atmosphere by the Mars Curiosity rover, that certain meteorites found on Earth thought to be from Mars were actually from Mars.

This raises a few questions in my mind

a. Do these martian meteorites contain significant quantities of extra-martian particles? (E.g. Those that belonged to the original asteroid/meteorite which impacted Mars, OR those that were collected during the course of it's journey through space)

b. How much velocity, and mass would the original meteorite have had to impart escape velocity to the rock? Is it possible to formulate these figures & say if a comet has mass X, and velocity Y it may impart escape velocity to Z mass of the impacted body?