I recently touched on the Q/V backhaul (v-band feeder link below) in two posts, as the onboard antenna for this link was disclosed in the recent video. This writeup will take a closer look into one aspect of that link. Attenuation.
DISCLAIMER NOTE: I am NOT an RF engineer. What I write here is just to the best of my understanding of the matter. I would very much appreciate people that work with these things to contribute with their thoughts. And please correct me if I got anything of this wrong.
Attenuation means the gradual loss of intensity through a medium.
It is a very common bear case to come across that the fairly new concept AST SpaceMobile uses of extremely high throughput Q/V-band links in the backhaul is:
"Impossible at that distance because of high attenuation in Q/V band."
Impossible. Strong word, and always delivered with no data to back that up.
Let's hear Wernher on that:
A few words from the father of the US Space program.
>“I have learned to use the word 'impossible' with the greatest caution.”
>
>Wernher Magnus Maximilian, Freiherr von Braun
Fun fact. The main purpose of Bluewalker3 in space tests are to test the backhaul link and integration to terrestrial networks, the left part of the image above. Fronthaul, the right part, is very much tested and set already, just in the other direction using Bluewalker1&2.
Why Q/V band? The good.
Spectrum is scarce and these higher band have not been put to extensive use, yet, and because of this broad bandwidths can be found and put to use. A broad band is what makes high throughput possible.
Attenuation in Q/V - band. The bad, but not that bad imo.
Attenuation. I added approximate numbers for cellular 2 GHz bands and the relevant Q/V-bands.
Recap, attenuation is: **the gradual loss
... keep reading on reddit ➡What are some pros/cons about beers with low FG? I’ve read they can be drier and sometimes thin but any more description?
I’m brewing a wheat ale, all grain 40%wheat 40%2 row 10% Munich, 10% Vienna and a small amount acidulated. Mash 152 x 60 min with mash out at 165. Intended to brew American wheat ale, LHBS didn’t have any of the intended yeast strains I was hoping for, ended up with Fermentis WB06, German wheat beer dry yeast. (Could have gone us05 and been truer to style but trying to branch out a bit). Fermenting at the colder side ~65F to minimize the ester production. Anyways Brew day comes I decide to only do a 30 min boil without calculating for decreased boil off as with a 60 boil. Expected OG 1.046 actual 1.040. I was worried beer might be on the thinner side but oh well. 10 days of fermenting were at 1.06 with an attenuation of 87%. I recheck yeast info and the expected attenuation is 86-90. Holy cow, not sure how I overlooked that, have never used a yeast with that high attenuation. Will be cold crashing and kegging in a few days.
What are general thoughts on beers that are lower OG and low FG? All grain no sugar or high fermentable additions. Thanks!
Anyone else gets very high attenuation with nottingham? My usual "house" aleyeast have been s-04 but I tried out nottingham to see how it compares. It took my 1.048 wort to 1.004 now in 4 days. Made me check calibration and pull another sample, tastes good too. Impressed!
This was a overnight mash so a little higher fermentability is normal for me then, 27L (~7gal) and one pack rehydrated to instructions, so the pitch was slightly on the low side as well.
Edit, it's a pretty plain pale ale. 6% carapils and 94 pale malt. Mashed in to 69C and insulated overnight.
Say 2 identical sources are the exact same distance from a window. Source 1 is exactly in front of the window at a distance of 20 meters. Source 2 is at an 80° angle to the left, also at 20 meters.
Would the decibel level inside the room be exactly the same on both occasions? Or does the very small angle for source 2 provide some attenuation?
Hi everyone. I'm new-ish to fiber. On a project I'm working on, we bought the wrong set of SEL FO transceivers and the work-around is to buy some fiber attenuators but I don't know how to do the math to find what level of dB attenuation I need.
I basically want to convert the 2815 to a 2814. For background, it's because our end-points are 100 feet apart. The 2815s are meant for 2-14 km use. They don't work now because of the distance issue. We need to attenuate the signal down to something usable.
This is the website I am trying to use but can't make sense of it.
https://www.thefoa.org/tech/ref/testing/test/dB.html
Any help is appreciated. Thank you.
Latest IPA has been at 1.015 for a week (three weeks fermenting in total.)
Starting gravity was 1.051. I've never had US-05 finish less than 1.011 before.
Mash temperature was slightly higher than usual 70°c (158f) but I usually mash at 68°c.
Would two degrees make that much difference?
I just found this:
https://pubmed.ncbi.nlm.nih.gov/32522071/
I'm not going to pay to find more than the abstract, but it seems to suggest rTMS is made less effective by neuroleptics.
Does anyone have any experience with the combination?
There are some studies on the use of rTMS for psychosis as well.
TMS seems promising, but I've noticed quite a few things (supplements, caffeine, herbs) don't seem to work as expected on invega (olanzapine may not have seemed as severe in this regard; presumably due to lower affinity for D2).
In a battle where an enemy deals damage from a specific element, but is weak to another, which is more efficient: mitgating their element, or increasing their weakness?
Example: Facing the Boiling Lizard. Does fire, weak to ice. Would Fire Rune help more than Ice Rune, or vice-versa?
Does anybody know what this means? My moms liver report tells us there are “Innumerable liver lesions low attenuation”
Time Stamps for all the things =
HEADPHONES = I am finally selling my trinity of TH-X00s which I never really did rotate into my normal headphone usage. Really hard to let them go, but its time I sell the rest of the collection as I have too many headphones.
TH-X00 Purple Heart = $560 shipped to CONUS. Only selling it as bundle = TIMESTAMP - Includes original box, all items in pictures and original Fostex carry bag. Wood and Cups are in great condition!
TH-X00 Mahagony = $460 shipped to CONUS. Only selling it as bundle = TIMESTAMP - Includes original box, all items in pictures and original Fostex carry bag. Wood and Cups are in great condition!
AMP = So purchased these in August 2019, cause my company was building a brand-new office and wanted to upgrade my setup at work. Well 2020 happened.... and we never moved into the office and so these never got used as they just sat in their box instead. Finally getting around to selling them. Has original logo design on them.
THX AAA 789 = $240 shipped to CONUS = TIMESTAMP = Includes everything originally sent to me as purchase from Drop. SOLD
EDIT: Just noticed I didn't get all the lint off the Purpleheart photo of wood cups. I will try and take a new picture later today and upload in addition to original one. Also happy to send more photos of any items if you want a more detailed look at anything. Sorry for the lint on the headphones.
I have spent time reading up on and familiarizing myself with a lot of different brewing calculations, one of which is the formula to predict the FG:
AA = apparent attenuation
FG = OG - (AA x OG - AA)
Example: FG = 1.050 - (.75(1.050) - .75) = 1.0125
Reading the book entitled "Yeast" (White & Zainasheff), they mention strategies of using multiple yeast strains on a brew, and on reading this, it broke my brain a little. Its the concept of combining certain strains that impart different fermentation characteristics to the final product. Sounds cool. But the impact on the calculations!
I suppose I could just take the average AA of all the strains and use that in the above formula, however I would be open to any more accurate, sophisticated models if they exist.
But it got me thinking: what if you pitch 100 billion cells of strain 1, and 50 billion cells of strain 2...shouldn't pitch cell count impact attenuation (and thus FG) as well?! Even for a single strain fermentation? I would imagine that if I pitch thirty (30) cells of a yeast strain into my 5-gallon wort, it will attenuate differently than if I pitch 300 billion cells, right? So why isn't pitching cell count an input parameter to the FG calculation?
For instance, suppose I have a stereo source which I’m inputting to the mixer as dual mono, panned respectively. When these channels are routed to the L+R main bus, is the main bus level higher than if the mono input channels were not panned before being summed? Otherwise, does the mixer employ a pan law and boost the non-panned signals’ sum to match the would-be panned case?
Like the title says, I brewed a Russian Imperial stout. My OG to start was 1.106. I pitched 2 packs of safale us-04 at 62°f and fermentation took off right away. After 3 days I slowly ramped the temp up to 68°f. Fermentation seemed to stop around 1.044 so I pitched a rehydrated pack of us-05 and slowly ramped up to 70°f over 2 days. The last gravity was slightly under 1.040. I plan on giving it another week before I cold crash but I’m wondering if it’s done.. is this a normal FG for a beer like this?
56% pale 2row 12% extra light dry malt extract 8% flaked barley 4% Crystal 120 4% Crystal 40 4% pale chocolate malt 4% flaked oats 2.5% Carafa 2 2.5% chocolate malt 2.5% roasted barley 1% brown malt (because I have it on hand)
Magnum hops at 60 min to 70IBU
Yeast S-04 at 62°f
Adding gypsum and cacl to water 0.7 sulfate to chloride ratio
Calcium around 105 ppm.
https://reddit.com/link/rmzq1p/video/a377oyc2nb781/player
I’m struggling to have good outcomes with adequate attenuation during my fermentations. (Last batch was 1.054OG and FG was 1.024 for a basic pale ale.)I make 1L yeast starters with one can of Fast Pitch along with one package of whatever strain of yeast I’d like to use for a 4-5gal batch. I also add 1tsp of DAP yeast nutrient at 10mins remaining in the boil. Any recommendations??
I just bottled a brown ale that finished with a higher than expected Final Gravity, and I'm pretty sure it's going to be the best thing ever, or, blow up my entire house in a furious explosion of glass shards (I'm being facetious, and I have an anxiety disorder, but you know what I mean).
I pitched WLP004 Irish Ale yeast and let it roll at 64-66F until the gravity dropped from 1.056 to 1.023 (according to my Tilt, which hasn't been calibrated on the low end). After about four days of active fermentation, it was steady at 1.023 for the next four days; then I let it sit at room temperature for another week and ignored it just because. Then I cold crashed, fined with gelatin, and let it come back up to room temperature before bottling. I assumed my Tilt was just reading off, and didn't bother to read my hydrometer until I had already filled the bottles, but the Tilt was actually pretty close; the FG turned out to be 1.020 which, by my math, is an attenuation of 64.3%. FWIW my recipe was about 10% Crystal 60 and 4% Chocolate malt, and I mashed at 155F. The low end of the attenuation for WLP004, according to White Labs, is 69%. I also primed to about 2.3 volumes.
Anyway -- now I'm wondering if I've got bottle bombs in store for me? Or will it just be a tasty brown ale with a little extra sweetness to it (which I like)? What do you think?
Sidenote, I'm glad I decided to bottle as much of it as possible in thick flip-top bottles. I put all of the crown-capped longnecks into a plastic tote, with as many of the flip-tops as I could fit, and put it all down in the basement where no one but me ever goes...just in case...
Hello, I'm a user of the Sonar software, and am overall very happy with it, I just have one problem with it.
I often listen to music while I play games, and after opting into Sonar, I noticed that my music volume gets turned down whenever I, say, shoot a gun. It also happens in Discord, but I don't have attenuation turned on in those settings. I am not a fan of this at all. I believe it's Sonar causing this, but I can't be 100% sure. Attenuation is turned off for all of the audio sources I use through Windows settings, and it still happens. I don't have any other applications that could be causing this. Any way someone might be able to help? Thank you!
I've been looking at the history of virology and I've seen a few things about the first rabies vaccine. Attenuation (making the viruse weak enough to not be a threat) can be done via passaging them through unrelated animals cells, drying them, exposure to oxygen, and heat.
Question. I've heard that you can hit them with X-rays and uv radiation to deattenuate them, but how useful is the success rate? I've heard that the UV radiation simply denatures the proteins so badly that they're point less for usage in vaccination.
P.s. how do they ensure the proteins are still useful after heating? Do they just heat them 'just right'?
I'm working on a concept involving sound placement. Some sounds - for instance, human speech - attenuate in a pattern that isn't really a sphere or a cone or a capsule - due to the occlusion of the head/body, it attenuates like this:
https://cdn.dpamicrophones.com/media/images/mic-university/facts-about-speech-fig07.jpg
Furthermore, different frequencies of speech (low, mid, high frequencies) attenuate at different rates.
Is there a way to implement a custom shape for attenuation? If so, I think I could apply band-pass filters to my source audio and then use a custom attenuation shape for each range of frequencies. Alternatively, I have seen that there's an "Occlusion Plugin" - is that really the direction I should be headed?
Trying to get rid of Discord's attenuation, and unlike in windows there is now slider to change the attenuation percentage. Could it be something I can change in Manjaro itself? Anyone else have this issue and get it figured out? Any help is super appreciated.
Setting up a Bobcat 300 at a friends house tomorrow and for now I will be using the original antenna (dont want to use something massive and cant put it outside since I don't want to be a bother. Would an indoor antenna work better placed by the window (second floor) on a sill or placed higher up in the room (second floor) where it is facing drywall then brick? We live in Canada so I assume the window will be a thicker kind for heat insulation. When looking at the attached picture, 1 is where the window sill is and 2 is where the higher position behind brick would be (signal may come through roof as well) Anyone have data for attenuation for brick vs windows? Thanks!
https://preview.redd.it/gd43wvu7t9z71.jpg?width=1284&format=pjpg&auto=webp&s=27d018c250d349e1ac968e12502abb0e88e98f70
Hello folks!
I have a question for those of You who own an acrylic custom IEM (created with the usage of ear impression) and have a comparison to the over-ear headphones with built-in active noise-canceling. Which solution is better in terms of environment sound cancelation (or noise attenuation in case of custom IEMs)? :)
Hi, I basically want to build a small module ( unsure if it has to be powered to achieve this) that will attenuate modular level audio outs down to line level. If possible I'd like to use potentiometers to achieve this.
Hyalp?
TL;DR: Make the diminishing returns of Damage Attenuation use a single formula that ensures a higher DPS always, predictably, and consistently leads to a higher actual DPS.
I know most people don't care about math but the recent discussions around the DR of Liches is a perfect example of how math has substantial gameplay impacts. The math matters, if you want good gameplay you have to have good math. I’ll be splitting this into a couple sections, each getting deeper down the well.
What is Damage Attenuation?
Damage attenuation is that annoying damage reduction (DR) effect that is currently making bad weapons better than good weapons when fighting Liches/Sisters. From what I’ve gathered this is done using your weapons stats. The game calculates a DPS based on the current stats of your weapon, including buffs from Warframe abilities, then applies a DR based on that DPS. This sounds simple but my lord DE has done everything in their power to make it complicated.
- For example, Eidolons have four different calculations for their fancy DR. Which equation is used is based on if it is a critical hit or not and a ratio of DPS to fire rate.
- Another example is Deimos Saxum. These guys have six different DR values, each their own equation that scales with DPS, which one is used is also based on DPS. None of these equations take crits into account (so crits effectively ignore the DR) and the damage from status effects have their own special DR.
- Demolishers (the Disruption enemies) use a similar system to Deimos Saxum but they also get the benefit of having six equations for their status effect damage.
- There isn’t any information as to what formulas Liches and Sisters use but I would be surprised if it weren’t equally as convoluted as the above.
If the above sounds like a load of cow poo then I am happy to say I 100% agree. Before we get to solutions I can see some saying “kill it with fire, remove all the fancy DR.” Before we get there I think it is important to go through why DE has put these things in place.
Why is Damage Attenuation?
At its most basic premise it is supposed to be a damage reduction scaling system that makes for a more consistent time to kill of an enemy across all levels of progression. It is supposed to make it so less geared players can do the same content as highly geared players where neither party has a 'bad' experience.
With the absurd levels of power scaling it is basically impossible for DE to pick a static EHP v
... keep reading on reddit ➡
