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Did you know?
  • The original Rudolph did not have a red nose. In that day and age, red noses were seen as an indicator of chronic alcoholism and Montgomery Ward didn’t want him to look like a drunkard. To complete the original picture, he was almost named Reginald or Rollo.
  • The Christmas wreath was originally hung as a symbol of Jesus. The holly represents his crown of thorns and the red berries the blood he shed.
  • The three traditional colors of most Christmas decorations are red, green and gold. Red symbolizes the blood of Christ, green symbolized life and rebirth, and gold represents light, royalty and wealth.
  • Tinsel was invented in 1610 in Germany and was once made of real silver.
  • The oldest artificial Christmas trees date back to the late 1800s and were made of green raffia (think grass hula skirts) or dyed goose feathers. Next the Addis Brush Company used their machinery that wove toilet brushes to create pine-like branches for artificial Christmas trees that were less flammable and could hold heavier decorations.
  • ‘Jingle Bells’ – the popular Christmas song was composed by James Pierpont in Massachusetts, America. It was, however, written for thanksgiving and not Christmas.
  • Coca-Cola was the first company that used Santa Claus during the winter season for promotion.
  • Hallmark introduced their first Christmas cards in 1915.
  • The first recorded date of Christmas being celebrated on December 25th was in 336, during the time of the Roman Emperor Constantine. A few years later, Pope Julius I officially declared that the birth of Jesus would be celebrated on that day.
  • Santa Claus's sleigh is led by eight reindeer: Dasher, Dancer, Prancer, Vixen, Comet, Cupid, Dunder (variously spelled Donder and Donner), and Blixem (variously spelled Blixen and Blitzen), with Rudolph being a 20th-century inclusion.
  • Outdoor Christmas lights on homes evolved from decorating the traditional Christmas tree and house with candles during the Christmas season. Lighting the tree with small candles dates back to the 17th century and originated in Germany before spreading to Eastern Europe.
  • That big, jolly man in the red suit with a white beard didn’t always look that way. Prior to 1931, Santa was depicted as everything from a tall gaunt man to a spooky-looking elf. He has donned a bishop's robe and a Norse huntsman's animal skin. When Civil War cartoonist Thomas Nast drew Santa Claus for Harper's Weekly in 1862, Santa was a small elflike figure who supported the Union. Nast continued to draw Santa for 30 years, changing the color of his coat from tan to the red he’s known for today.
  • Christmas 2018 countdown has already begun. Will you be ready???
  • Why do we love Christmas? It's all about the traditions. In this chaotic world we can miss the "good old days." Christmas reminds us of that time.

Titanium48

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About Titanium48

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    Edmonton, Alberta, Canada
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  1. Titanium48

    Led Keeper?

    I just bought one today ($29.99 at Canadian Tire). The good: It works. Much more convenient that testing every diode one by one with pins (to poke through the wire insulation) and a multimeter. The not so good: Somewhat flimsy construction. The plastic mechanism seems barely adequate to deliver the amount of force needed to push the pin through wire insulation. One must take care to ensure the wire is properly centered in the mechanism or the pin that pokes into the wire will bend. I had to straighten it a few times before I was done with one string. It doesn't light up the LEDs very brightly. Once you get the wire piercing mechanism figured out you will find that the brightness is inadequate if you are working outdoors during the day, even if it is cloudy. Plan to fix your LEDs indoors or at night. My repaired string is now significantly dimmer than before an LED died. It is possible that this degradation and the original failure have a common cause, but I suspect this is a result of the "pod" having too much resistance. The pod that I used contained a 330 ohm resistor, which will drop 6.6 V at 20 mA, equivalent to 2 or 3 LEDs.
  2. I'd go for LEDs of some type. You are obviously no stranger to DIY electronics, so I don't think you will have any problems with the required hardward modifications. I think there is a good chance of getting them to work in sets of 10, and it should still look good if you have to go to 8 or 9. Rewiring your SSRs for 120 V and using C7 retrofits is also an interesting idea, especially if you want to make your numbers bigger. While the retrofits don't consume a lot of real power, the capacitors do result in a fair bit of reactive power in your circuits. Design for 2.5 VA (20 mA) each.
  3. Titanium48

    C9 Lights Indoors?

    My family used C7s on our real trees when I was a kid, and we preferred the deep blue and violet ones that heat up the most. The needles next to the bulbs would dry out and start to fall off before those on the rest of the tree, but there was never any evidence of scorching. C9s are 7W instead of 5W, but the bulbs are much larger so they don't get any hotter.
  4. While the LED manufacturers do provide color temperature specifications for their products, the decorative lighting manufacturers don't seem to like to pass that information along.
  5. Do you have an electric stove or clothes dryer? Does the same thing happen when you turn them on?
  6. A 25 bulb C9 string will draw 1.5 A, so you could probably connect them in sets of 3 and use 2 extension cords. If you don't want to run more extension cords, look for some commercial grade lights that use heavier guage wire. Put the heavier guage strings closest to your outlet and the lighter ones at the far end. Here in Canada, C9 strings are built with 18 AWG wire and are rated for 1250 W (7 strings). Unfortunately we have to pay for that extra copper - 25 bulb C9 strings cost $10 each here.
  7. White LEDs typically have a voltage drop in the range of 3 - 3.5 V at rated current, and will still turn on at reduced current (and brightness) at voltages down to somewhere in the 2.5 - 2.8 V range. 24 VAC RMS will have a peak voltage close to 34 V, which will allow the LEDs to turn on for at least a small period of time each cycle. If the LED voltage drop is near the upper end of the normal range, that period will be short, peak current will be low and the LEDs will appear dim. If the LED voltage drop is somewhat lower, you will get a longer on period and a higher peak current and the LEDs will appear brighter. If the voltage drop is near the lower end of the normal range, you will need to add a resistor to the circuit to keep the peak current from becoming excessive and shortening the LED lifetime. Personally, I wouldn't bother trying to look up specifications. I'd just find LEDs I liked and work out the ideal circuit parameters empirically with a multimeter and a variable resistor like I described above. If you are lucky, you will get a reasonable current with a string of 10 and zero extra resistance and everything will be plug and play. If the current starts to get too high as you dial down the potentiometer, you will need to add a resistor to each of your sets of 10. If they stay too dim even without added resistance, try again with one less LED. If you are into specifications, the electrical behavior of an LED can be modelled with two parameters - the threshold voltage and the dynamic resistance. Below the threshold voltage, an idealized LED behaves as a very high resistance and conducts a negligible current. Once the threshold voltage is reached, current increases in proportion to the amount by which the applied voltage exceeds the threshold. This leads to a modified version of ohms law, where the voltage you use to calculate current is the applied voltage minus the threshold. The threshold voltage for white LEDs is near 3 V, and dynamic resistances are quite low, no more than few dozen ohms and sometimes as low as 4-5 ohms for high power LEDs. Thus a voltage increase of 0.5 V or less will take an LED from barely turning on to maximum current. Real LEDs don't have quite as sharp a cutoff as the simplified model suggests, and actually begin conducting low but detectable currents a bit before the threshold.
  8. Nearly all of the small, cheap LEDs used in decorative lights have a maximum current of 20 mA and in a series circuit the full current flows through everything in the circuit, so you want 15-20 mA regardless of how many LEDs are in the string. With clear (white) LEDs, you might even try plugging in a set of 10 the exact same way you would with incandescents - there is a chance that they will work just fine with no extra parts at all. If you choose to give it a try, just do one set until you have confirmed that it works. The margin between undercurrent (which will make them dim) and overcurrent (which will drastically shorten their lifespan) is small when there is no extra resistor.
  9. Cutting out a LED and splicing the set back together will increase the current for the remaining LEDs and could shorten their life (this is true of incandescent minis as well). However, I have put about 1000 hours on a string after I cut out a defective LED and it still works fine, with no detectable loss of brightness. YMMV
  10. America's touque eh? I'm assuming you mean Canada. In addition to all of the usual reasons we pay more for things here, there is a significant difference between Canadian and American decorative light strings. All decorative light strings (C9, C7 and mini, both LED and incandescent) must be built with 18 AWG wire to be CSA approved for outdoor use, while US minilight strings use 22 or even 24 AWG wire. A 100 count Canadian minilight set contains about $2 worth of copper, while the copper in a US set is only about $0.50. This raises the price of both incandescent and LED strings, but makes the price difference seem smaller. This is also why Americans aren't supposed to connect more than 3 strings of incandescent minis end to end, while we can connect 15 incandescent strings (or 600 W of LEDs) without issues.
  11. 24 VAC should run 10 red, orange or yellow LEDs easily. 10 green, blue or white may work, but they might be a little dim unless you cut the string down to 8. With 8-10 LEDs in series on a 24 VAC supply, you won't need any extra diodes if you are OK with halfwave flicker. The peak inverse voltage will be 4.3 V per LED for 8 LEDs (3.4 V for 10) and most LEDs can handle up to 5 V PIV, so the LEDs themselves can do the rectification without damage. For fullwave, bridge rectifiers can be purchased as units or assembled from 4 individual diodes. You will need to determine the correct polarity of your strings if you go fullwave - you can test a single diode with a multimeter or just hook up the whole string (with a resistor) to the power supply to test by trial and error. You can find the resistor value empirically if you don't know the specs of your LEDs. Assemble your string in series with a variable resistor (potentiometer) and a multimeter on the mA scale. Make sure the potentiometer is dialed up to maximum resistance and connect the power supply (through the bridge rectifier if you are using one). Turn the resistance down until you get a current of 20 mA, then dissasemble and use the multimeter to measure the resistance of the potentiometer. Choose a resistor of equal or slightly higher resistance.
  12. I agree with those who suggest LEDs. They produce a much brighter, more pure and intense blue than any incandescents and they never fade, even if you leave them up all summer.
  13. You could power a standard set of LEDs with batteries, but you would need a LOT of batteries (about 80 1.5 V alkalines, or 10 car batteries). If you want to use a reasonable number of batteries you would need to rewire the string to put fewer LEDs in series to lower the voltage.
  14. Given how hot and humid it gets in your part of the world I don't envy your power bills either. We can use natural gas for heat (1/3 of the price of electricity) but there isn't much alternative to electricity for A/C. I might enjoy winter in your neck of the woods, but the hot, humid summers in the SE part of the continent don't sound pleasant at all. I'm looking for air conditioning whenever the temperature gets over about 25
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