From the output of the pre-amp, the microphone signal is sent down two different paths. It feeds both one pole of Sl-a and the phase-inverter. The phase inverter is nothing more than a second NE5532 configured as a unity-gain inverting op-amp (IC2-a). The output of IC2-a is connected to the other pole of Sl-a. That way, Sl-a can select either the inverted or the non-inverted signal. The selected signal on Sl-a’s common pole goes to potentiometer R14-a. That potentiometer sets the level of the microphone signal feeding the headphone amplifier.
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Nails should be hand sanded and coated with a rust inhibitor primer, followed by at least 2 coats of paint. Resin staining can be cleaned using a mixture of equal parts denatured alcohol and water; rinse thoroughly, and dry. When completely dry, seal using 1-2 coats of stain blocking primer. Allow 48-hours between coats, and then paint as you normally would.
Removing Minor Damage
Class II conditions include crazing (fine cracking), intercoat peeling, solvent blistering, and wrinkling. Crazing is caused when multiple coats of paint become hard, dry, and brittle, and can no longer expand and contract with the substrate material. This results in interconnected hairline cracks in the top layer of paint. Hand or tool sanding followed by a fresh coat of paint will seal moisture from the cracks, even though cracks may still show. Intercoat peeling; usually the result of either improper painting preparation, or incompatibility between coats of paint, such as latex over oil based. The surface should be carefully scraped to remove all loose paint, and then thoroughly cleaned. Apply a high quality oil based primer once completely dry, and then either an oil base or latex paint. Solvent blistering. A rarely-seen error in paint application, caused when solvent-rich paint is applied in direct sunlight. The surface dries too quickly; solvents are trapped beneath the dried film. As they come to the surface, they cause blistering. Any blisters should be cut open to determine whether they are caused by moisture or solvents. If another layer of paint is visible beneath, the problem is probably solvent blistering; if bare wood is underneath it is likely due to moisture. This can be remedied by scraping or sanding to a sound surface, and repainting; avoid painting in direct sunlight. Wrinkling – another error in paint application caused when the top layer dries before the layer underneath. This can be caused by several factors: * Applying paint too thick * Not allowing adequate drying time between coats * Improper brushing * Applying paint in excessive heat conditions. The output of the headphone amplifiers is coupled to output jack J3 through R21. That resistor provides overload protection to IC3-a in case the output is shorted. If you have never used an op-amp for driving headphones before, you are in for a nice surprise. The NE5532 will supply a 10-volt rms signal into a 600-ohm load with very little distortion. That works out to 166 mW of power. Most personal stereos only supply 20 to 30 mW of power to headphones. Wrinkling is corrected by scraping or sanding to a smooth finish, and then repainting following paint manufacturer recommendations. Removing Excessive Damage Class III conditions consist of peeling to bare substrate, or severe cracking or alligatoring. These conditions require complete removal of existing paint. Peeling most commonly occurs on wood substrates; caused when moisture collects between the paint and substrate, greatly affecting paint adhesion. Peeling usually begins as blisters that accelerate as moisture swells wood substrates. This breaks down adhesion, resulting in cracking and peeling. 1. Belgium gets new government, but how long will it last? data: 27.03.08 After a nine-month political crisis that prompted speculation that the country might split, Yves Leterme of the Flemish Christian Democrats was sworn in Thursday as prime minister. But many voters believe the new government will be too weak to last. 2. European cargo ship docks at International Space Station data: 07.04.08 A new European cargo ship flew up to the International Space Station, successfully delivering food, water and clothes in its orbital debut. 3. Omagh civil case due before court data: 07.04.08 A civil action against five people relatives believe were behind the Omagh bombing is due to begin. 4. David Beckham's new tattoo data: 19.03.08 David Beckham appears to have chosen an ancient Chinese proverb in what is the latest addition to his tattoo collection. 5. Cricket: Pakistan hammer B'desh data: 10.04.08 Mohammad Yousuf hits his 15th one-day international century as Pakistan crush Bangladesh by 152 runs in Lahore. 6. Blast kills Sri Lankan minister data: 07.04.08 Sri Lankan Highways Minister Jeyaraj Fernandopulle is among 14 people killed in a suicide bombing, officials say. 7. Alzheimer's blood test 'promise' data: 07.04.08 A US company hopes to be the first to market a blood test to detect early signs of Parkinson's and Alzheimer's. 8. Move to end 'student ghost towns' data: 10.04.08 The government may use planning laws to end concentrations of student houses in England. 9. Robots fly into Antarctic skies data: 19.03.08 A pair of lightweight, robotic planes have made the first unmanned flights over Antarctica's icy expanses. 10. Udo Voigt, leader of German far-right party, charged with defamation data: 27.03.08 Voigt, head of the National Democratic Part, was charged Tuesday with incitement and defamation for allegedly publishing a pamphlet before the 2006 soccer World Cup that prosecutors said called into question whether nonwhite players should be on the national team. 11. Extra troops to be sent to fight Taliban data: 07.04.08 Britain is poised to send another 450 troops to Afghanistan and take control of its most war-torn region for at least the next two years following pressure from the United States, The Daily Telegraph has learned. 12. Pernod Ricard buys maker of Absolut vodka data: 07.04.08 The acquisition by the French company combines Vin & Sprit's Absolut with Pernod's brands, which include Seagram's gin, Havana Club rum, Chivas Regal Scotch and Jameson Irish whiskey. 13. U.S. to cut staff at its embassy in Belarus data: 27.03.08 The United States will cut staff levels at its embassy in Minsk by almost half, bowing to demands from Belarus amid worsening relations between the two countries, the Foreign Ministry said Monday. 14. Kevin Maguire: Tories ahead on own goals data: 10.04.08 Rarely have crocodile tears flowed so shamelessly as when dewyeyed toff David Cameron sniffed an onion and posed as unlikely champion of the lower paid. 15. Fed loses its unified voice data: 10.04.08 As the U.S. Federal Reserve Board deals with the biggest American financial crisis in a generation, its policies are coming under criticism from within. 16. Turkey's high court to hear case against Islamic party data: 07.04.08 The court voted unanimously to hear a case that seeks a ban on the prime minister's Justice and Development Party. 17. Female British spy's exploits during World War II are revealed data: 07.04.08 A British spy who helped lead the French Resistance during World War II outfoxed the Nazis by concealing secret messages in the hem of her skirt, according to records unsealed Monday. 18. Chaos complicates life for Walsh, chief executive of British Airways data: 07.04.08 The financial year just ended was supposed to mark a turnaround but just when Walsh should have been planning celebrations, he was juggling record fuel prices, economic malaise and Terminal 5 troubles. 19. 'Mother' held in Shannon inquiry data: 07.04.08 Unconfirmed reports say a woman arrested over the alleged abduction of Shannon Matthews is her mother. 20. US envoy may challenge for Afghan presidency data: 10.04.08 The Afghan-born US Ambassador to the United Nations, Zalmay Khalilzad, has signalled that he will run for the presidency of Afghanistan in elections next year. 21. Qatar to upgrade Losail circuit to F1 standards data: 27.03.08 Qatar plans to improve its Losail MotoGP circuit to cater eventually for Formula One, the head of the Gulf country's motor sports federation said on Wednesday. 22. Disney celebrates its perfect partnership data: 10.04.08 Bob Iger, chief executive, calls Pixar as the 'new DNA' that has revitalized the studio's film output and revived its glory years as an animation powerhouse 23. Barack Obama's key race speech in full data: 19.03.08 Barack Obama's key race speech in full 24. London's mayoral race offers plenty of bluster and blunder data: 07.04.08 The election, between Boris Johnson and Ken Livingstone, has become a litmus test of the national political mood and an important referendum on Prime Minister Gordon Brown's wavering Labour government. 25. 54 Burmese migrants suffocate in truck data: 10.04.08 At least 54 illegal Burmese immigrants have died of suffocation while being smuggled into southern Thailand in a freezer truck, police have said. 26. Greece gripped by pensions strike data: 19.03.08 Greece's civil servants hold a general strike against pension reforms, paralysing transport and closing public offices. 27. EU threatens a mozzarella ban data: 07.04.08 EU officials Thursday threatened Italy with a possible Europe-wide ban on mozzarella from the Campania region unless Rome provided more details about production of the cheese, samples of which were found to contain higher-than-permitted levels of dioxins. 28. Andrew Flintoff's mansion plans demolished data: 10.04.08 Andrew Flintoff, the England cricketer, has been forced to withdraw plans to build a five-floor house in a Cheshire village after fierce complaints from neighbours. 29. Afghanistan's youngest migrants adrift on the road to asylum data: 27.03.08 Hundreds of child refugees from Afghanistan are camped at a port in western Greece, hoping to sneak onto a ferry to Western Europe. But the boys, as young as 8, are being preyed on by traffickers. 30. Science fiction author Arthur C Clarke dies data: 19.03.08 The Science fiction writer Arthur C Clarke, author of more than 100 books, has died at the age of 90. --- --- --- -x- |