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treks

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Everything posted by treks

  1. It's very easy to beat Celestrons, since they are mass-produced in China, as most other makes are. As a point of interest, when you compare "identical" scopes from the same Chinese factory, you will almost certainly get as many different test results as the number of scopes you are testing.
  2. One of my suggestions would have been to build your own scope, but be wary of the lenses/mirrors you get in these kits. You may strike it lucky and get decent optics, but in my experience, you need a great deal of luck for this to happen. Just as a point of interest, what was the PVC scope compared with?
  3. OK, so we are going to have to this ourselves. Can you give me an estimate on the amount of money you want to spend? If you have about $1000 US available, I can make some suggestions that will get you going with the least amount of hassle.
  4. OK, it seems I misread the quick Google search I had done for astronomy clubs there. I have found this though- http://www.althurayaastronomycenter.ae/about-us Is that still in operation, or has it also closed up shop?
  5. OK, the smallest instruments that would give you decent views of the ring system fall into the 150mm aperture range, but the type of views you ultimately get depends entirely on your budget. For instance, refractors are best for planetary viewing since they (mostly) eliminate chromatic aberration, but these are also the most expensive scopes. You could get a much cheaper Dobsonian reflector which gives decent planetary views, is easily transportable and easy to use because you don't need to to polar align, but the downside is that Dobsonians are prone to suffering from heat currents in the tube, which distorts views. Moreover, the bigger you go on aperture, the more heat currents and other atmospheric disturbances are magnified, so you may have to install small extractor fans in the tube to get even halfway-decent views immediately after sunset or in the early evening until the desert cools down a bit. All things considered, my advice would be to join one of the many astronomy clubs in the UAE on an outing before you decide on what to buy. Clubs are always glad to show newcomers the ropes, and besides, they will know where to get the best scopes at the best prices. Buying an expensive scope at this point could be a costly mistake.
  6. I'm an advanced-level amateur astronomer in my other life. Give me a shout if you want advice/tips about small telescopes.
  7. Auction fever does not only apply to cars. I've seen people afflicted by auction fever buy all sorts of used rubbish for twice or even three times the amount they would have paid for a new piece of rubbish, but I guess that is how auctioneers make much of their living.
  8. I use waterless coolants in my cars, and I have not seen them running hotter than normal. However, I keep forgetting that I don't live in a desert, so I agree with @desertdude on this one- I would not use these coolants in extreme temperature conditions, either. Nonetheless, if I were in Gaurav's shoes, I would flush the cooling system several times, before refilling with Mitsubishi-approved coolant mixed in the correct proportions to achieve the right specific gravity for the mix. Then, I would never add any other brand, formulation, or concentration of coolant- ever. The best way to preserve the coolants efficiency is to mix a small amount in the correct proportions, and then to add the mixture to the system to top off the coolant level, as opposed to adding either pure coolant or pure water- both of which could and probably will, change the mixture's density, and hence, its effectiveness.
  9. Not wanting to start an argument here, but did you actually rinse the sediment under clean water, and found grains of desert sand? Or did you just squeeze the sediment between your fingers and found the sediment to be granular? This is an important point since pure silica (sand) will not discolor the coolant, so unless you have been kicking up sand that contains clay particles (that would certainly have discolored the coolant), the coolant should have remained clear. But, @desertdude makes a good point. If there was a lot of sand flying around the engine bay just at the point when the cooling system sucked in coolant from the expansion tank, some sand could conceivably have entered the tank through the overflow tube. In my experience however, granular material in expansion tanks sometimes sticks to a magnet, in which case it is rust. If it does not stick, it is obviously not rust, and likely to be the result of chemical interactions between different types of coolant in the water, and/or reactions between coolant mixes and some metals in the cooling system- most notably, some aluminium alloys in some radiators. @Barry, also makes a good point- waterless coolants eliminate all of these issues, and although it is more expensive than regular coolants, their overall performance and protection levels are miles ahead of anything you can mix with water.
  10. Another issue with coolants is that different brands/formulations have different densities, so apart from anything else, if you mix coolants it can happen that the lightest coolant floats on top of the more denser coolant when the engine does not run. This is very likely the reason why you are seeing green coolant when you open the radiator cap, but if you should drain the radiator from the bottom hose, you will almost certainly see another color coolant coming out first. Moreover, since not all coolants are compatible, mixing coolants can destroy the rust protection function of all the coolant formulations in the mix, which is the origin of the corrosion-colored coolant in the expansion tank.
  11. I have used synthetic rope on my African expeditions, and apart from the fraying issues with steel wire, I'd much rather use a synthetic rope in difficult situations because it is lighter and easier to use than a heavy steel cable. It is also safer, because compared to a steel cable, it has much less backlash when it breaks, which is perhaps its greatest advantage over steel ropes.
  12. The Germans were not exactly ripped off. They were so far ahead of everyone else that nobody was in a position to actually rip them off, so what the Americans did was to transplant the German rocket program (scientists included, except for those that the Russians got hold of first) to US soil. True about the JLR case, although that case represents the exception that proves the rule.
  13. I agree with most of what of you say, but perhaps China will be demonized less when they get the issue of Government-approved theft of intellectual property under control.
  14. I think we need to define the word "legend",and what it means to different people. For instance, some people see the Tooth Fairy, the Easter Bunny, and Santa Claus as legends, while others consider vampires, sea monsters, trolls, and goblins as legends. There are many other examples but in which category of legends do Jeeps fall? The warm and fuzzy kind, or the kind that nightmares are made of?
  15. I am surprised by the fact that you have listed only two Jeeps If receiving the jackpot is contingent upon spending it on cars, then I will remain both jackpot-less and car-less because I refuse to pay the ridiculous asking price(s) for cars I cannot use. I have two already, and more would just be a waste- no matter how fast or shiny they are...
  16. ...and they managed to set the bar very high in the process; it will now be extremely difficult for any manufacturer the beat the sheer ugliness of this monstrosity.
  17. I lost one of these in the Central African Republic. Best vehicle for almost every off road application,ever. OK, maybe not for rock crawling, but it can handle almost anything else.
  18. ...or you simply have to wait for the crankshaft main bearings to wear out, which usually happens sooner than expected. Translation: I have also changed more than a few of these engines and while they were all also still running when I replaced them, all of them had oil pressure issues caused by worn main bearings.
  19. Not necessarily. For instance, everyone (including Governments) is talking about eliminating petrol and diesel vehicles within twenty years, and in some cases as soon as ten years, and yet, nobody has thought about the fact that there simply is not enough power-generating capacity in the world to charge hundreds of millions of electric cars.
  20. I suppose this system is fitted with some sort of automatic guiding system that will place the pick-up back in the slot after overtaking a slower vehicle?
  21. Gaurav is right of course, but few people carry water consumption calculators, and when they do, they don't always take them seriously. Nonetheless, a rule of thumb that I learned during my military service in the Namib desert is that drinking a liter of water every hour (spread out over an hour) keeps you more evenly hydrated than drinking a liter of water once every hour. And as @shadow79 said, adding a tiny pinch of salt and a few drops of glucose to every liter of water you take during a hot day goes long way toward maintaining your electrolyte levels.
  22. I agree with @Barry on this. The steering angle sensor forms the heart of several safety systems, and a trying to get out of a dangerous situation is not the ideal time to discover that the steering angle sensor re-calibration procedure was not performed. I have never understood why it is even possible to clear steering sensor codes without performing the required re-calibration procedure. I would have thought that manufacturers would make it impossible to clear these codes, but what is worse is the fact that I have known mechanics who did not know that a re-calibration procedure had to be done, and who then spent days trying to figure out why the ABS, stability, and traction control systems don't work
  23. Thanks, @Barry, I was wondering about the type of gift you sent me, hence my need to contact you privately. However, I have not experienced a flood of PM's, so I will redeem the points but when I do start to get PM's,for stuff that should properly be in the forums, I will donate the points to @desertdude.
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