F region
That portion of the ionosphere existing between approximately 160 and 400 km above the surface of the Earth, consisting of layers of increased free-electron density caused by the ionizing effect of solar radiation. Note 1: The F region reflects normal-incident frequencies at or below the critical frequency (approximately 10 MHz) and partially absorbs waves of higher frequency. Note 2: The F1 layer exists from about 160 to 250 km above the surface of the Earth and only during daylight hours. Though fairly regular in its characteristics, it is not observable everywhere or on all days. The principal reflecting layer during the summer for paths of 2,000 to 3,500 km is the F1 layer. The F1 layer has approximately 5 ´ 105 e/cm3 (free electrons per cubic centimeter) at noontime and minimum sunspot activity, and increases to roughly 2 ´ 106 e/cm3 during maximum sunspot activity. The density falls off to below 104 e/cm3 at night. Note 3: The F1 layer merges into the F2 layer at night. Note 4: The F2 layer exists from about 250 to 400 km above the surface of the Earth. The F2 layer is the principal reflecting layer for HF communications during both day and night. The horizon-limited distance for one-hop F2 propagation is usually around 4,000 km. The F2 layer has about 106 e/cm3. However, variations are usually large, irregular, and particularly pronounced during magnetic storms.
The Urban Dictionary Tee
I really love it it's me through and through. Thank you. And when I want another shirt made I will be going through you guys.
ThIs is perfect
Great quality and fast shipping and I just dropped my mug.
This T-shirt is a high quality product. It fits perfectly and is very comfortable as well. I'm totally satisfied with the product and recommend it to everyone. Not to sound like a commercial or anything, but I really am impressed! Check it out for yourself. If you're thinking about buying something, go ahead. I'm sure I'll be buying more for a few friends soon. Thanks guys! I love this shirt! For real.
My niece laughed and loves her custom shirt.
Not only was the product exactly what I expected, I was well informed on the shipping process in a seamless and timely manner!
The T-shirt was a birthday gift for my girlfriend and she absolutely loved it.
Happy that this tee is comfy and fits well. I wish the sentence was on the back too.
My wife absolutely loves her new T-shirt.
This looks like a weird design but it looks cool
This T shirt is the best piece of material to have ever graced this Earth. The fine quality fabrics and in depth definition, which is professionally implanted on the back of the shirt, which makes for some very interesting talking points. Thank you Pablo Parmesan.
Absolutely wonderful product! I bought this shirt for my son and he gagged with joy! Mariah Careystmas everyone!
I love it I bought me and my family some
Glad I had utmost FREEDOM OF SPEECH to express in articulate detail what evv it is the fk i was on a rant about that day. I haven't even received my shirt. I just a few moments ago placed the order. That is how pleased 😄 I am. Fk yeah fk yeah. Very empowering experience. My thoughts turned into type, that made some shi# happen. Having freedom of expression was most definitely...one fk ton of fun. A fk ton can be quantified as exuberance an joy beyond expectation. Fk yeah fk yeah. Awesome>>>
Proofread much? She might seem "quite"? Please fix the spelling to "quiet". Can't believe I was considering this purchase...
Damonism T-shirt :+) I found this by accident while surfing through your site. I love this shirt. I bought one and wear it when I feel frisky.
Another hit!
Great shirt, great service. A big thumbs up👍🏻
I always get so many compliments when I wear this (my favorite) shirt. I have been able to give out my phone number to lots of nice old men and my parents think it's great that I have so many nice mentors grooming me into a nice young boy who is willing to "follow the rules ".
Very comfortable and love the tyoeface
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Size Guide
Measurements may vary by up to 2" (5 cm). Pro tip: Measure one of your t-shirts at home and compare!
A - Length
Measure from the top of the collar to the bottom hem
B - Width
Measure across the chest from armpit to armpit
Size Chart
| Size | Length | Width |
|---|---|---|
| XS | 27" | 16½" |
| S | 28" | 18" |
| M | 29" | 20" |
| L | 30" | 22" |
| XL | 31" | 24" |
| 2XL | 32" | 26" |
| 3XL | 33" | 28" |
| Size | Length | Width |
|---|---|---|
| XS | 69 cm | 42 cm |
| S | 71 cm | 46 cm |
| M | 74 cm | 51 cm |
| L | 76 cm | 56 cm |
| XL | 79 cm | 61 cm |
| 2XL | 81 cm | 66 cm |
| 3XL | 84 cm | 71 cm |