My work had found a Nighthawk WR-200. Two months later, I was still the only one questioning about it. I now own it and after seeing this video, I am so keeping this $200+ watch. Such an amazing tool in a small package.
Thanks for making this video man! I just got my first Citizen Skyhawk model JY8075-51E, and the only thing I haven't quite figured out was the slide rule. All I'd really like to use it for is basic multi/div here and there. This video made that simple. Thanks!
@@nikudes quick question. Since the reference point is the number "10," I assume you can't do any math with numbers less than 10? Since the scale goes from 10-99?
Thank you for your help, I'm taking college algebra, & we're doing a lot with average rate of change & fuel! This will help! I have the Skyhawk Titanium.
@schitlipz Yes there is a way to find roots. It's sort of like doing a division problem. To divide 20 by 40 for example, you'd move 20 on the outer bezel ring opposite 40 on the inner ring and read the answer opposite 10 on the inner ring: 50 (meaning 0.5 because you have to figure the decimals out on your own). But you want the square root, meaning the condition in which both multipliers are equal.
@negolatak I refer to the number 10 on the inner ring as the "point of origin" because that's where one starts counting numbers. It's the equivalent of zero. It just means that if you divide any number on the outer ring by the one underneath it on the inner ring, you can find your answer on the outer ring opposite the point of origin (which is the number 10 on the inner ring). Does that make sense?
@nikudes So to find the root of 20 turn the bezel until the number opposite 20 on the outer ring, and opposite 10 on the inner ring, are the same. In this case that's about 45 (meaning 4.5). The square of 20 is actually about 4.47.
10 лет назад
Thanks, I found only this video for EB6! It is useful, I have C460 but I had looked for explainition a couple years ago. But sadly I leave in europe, and we counting in liter and kilometers.
the speed your using is MPH, but worldwide aircraft speed is usually measure in KNOTS or Nautical Miles/hour ? so how do i measure the rate/time/distance if i want to use KNOTS then ?
@nakmos14 It really should be "units/hour." You can use any units you want, e.g. mph, knots, kph, gallons/hour, liters/hour, and the calculations will still work. Try it out.
Thanks for posting- Great video! Can you recommend an inexpensive watch that can do the rate/time conversions? All I can find are the 2 ring slide rules for $100 + Thanks!
@Karlaaa94 This is model was only available in Japan, as far as I know. There are some US models that don't have the arrows. Try searching for model JR3060-59F or JY0005-50E. Good luck.
The one on the left is a 24 hr. hand for local time. The one on the right shows hours and minutes for UTC time, also on a 24 hour dial. UTC is Universal Coordinated Time, sometimes called Greenwich Mean Time. It's the time at the 0˚ meridian near London.
@nikudes Yeah, I was messing around with the root thing and figured the "fine-tuning" thing. It's not particularly helpful because because finding two similar numbers at different parts on the bezel isn't a quick operation. Also, more importantly, square roots (or third, fourth, etc) have two values depending on the decimal position. Example: root of 7 and 700 are numerically the same, 70 and 7000 too, though different. I'm not sure why, but if you read the value at root 10 ie 3.16
Brother kindly make a video on adjusting and setting up the watch i have bought my first ecodrive it is c650 which is quite smiliar to yours i tried my ass off but i dont have any idea what is going on i tried watching videos reading manuals but nothing seems to work in my case it would be nice if you could help somehow.
@bestvidsdottk Most slide rule bezels, this one included, have marks on one of the rings for simple conversions like this. In this case you'd line up 12 (remove a zero) on the mark labeled "STAT.," which stands for "statute miles." Opposite the mark labeled "KM." (for kilometers) you'd read off the number, in this case about 19.3. Move the decimal over one to the right (basically the opposite of what you did before) and you end up with 193, so 193 kph.
Citizen eco drive sky hawk? :- 1) Which colour is the watch light? 2) What is the reason for night light showing red colour? 3) Does it automatically change 1 hour forward or backward automatically without manually setting?
I think it was called the Navihawk 2000GT. It was a Japan-only model. The watch lights up blue-green. To change from daylight savings time each time zone needs to be adjusted manually but it's fairly quick to do. Which red light are you referring to?
awesome video! thank you so much for teaching this! I'm a little disappointed with Citizen. I think that rate time/ distance feature is the coolest. I have the Blue Angels edition of the nighthawk and they removed the hour markings from the inner bezel. You'd think a high quality aviation watch would be sure to have that, =( thanks for making the video though :-)
@bestvidsdottk You can also do it using the multiplication method I describe in the video but then you have to know the conversion factor between mph and kph, which is about 1.6. So 120 mph x 1.6 = about 192 kph. So I was a little off in reading the bezel in my earlier reply.
Doing rate/time/distance calculations with a normal slide rule would be just like using a calculator. You'll get time in decimals (2.5 hours, for example). Search online for an E6B flight computer. It's like a slide rule but it has a time ring. They're about $25. That might be just what you're looking for.
@BrianTakesValium No, but those ratings can be confusing. Look up "diving watch" on Wikipedia. The section called "Water Resistance Classification" should clear things up.
Inaccurate to say the least. My God, 3*3 is a tad greater than 9. And the manual has some bad translation on finding roots (very bad translation). I've got a titanium btw. In any case, do you know if roots can be found using this exact similar bezel or is it a page they should have left out of the manual? Thanks in advance, bro. Wow. In one week I've found half dozen ways this watch could be better.
I love my skyhawk to, but it seems that the digital display is bad to see when the watch is tipped forward. Even tough this is an unnatural arm movement, even looking straight at it, it is less visible then when you tip it backwards. Or is that just my skyhawk?
@negolatak I'm not sure. Slide rules usually start on 1. you could think of 10 as 1.0 and 11 as 1.1 because the decimal point depends on how you define the numbers. But why no zero? I don't know. You'll have to ask someone better at math than I am.
I'm not a pilot so I'm not sure but I have heard of analog flight computers (from what I understand, they're a bigger version of a rotating slide rule on this watch). I think the watches were just meant as back-ups.
+Time4achange Thanks. 10 is the origin for multiplication and division. The yellow arrow at the top of the inner ring is the origin for rate/time/distance calculations. Fahrenheit to Celsius is a little trickier. If the conversion points were on the bezel that would be easy but I don't think they are. The formula is °C = (°F - 32) / 1.8, so you'd take your ˚F number, subtract 32 (in your head), and divide the result by 1.8, that is, find your result on the outer ring, then spin it until it's opposite 18 on the inner ring (that's the 1.8) and then read the result opposite 10 on the inner ring (your origin).
I'm not sure what you mean by starting at 10 . You may start anywhere , depending on the calculation you are doing . if for example multiplying 2 by 2 ,start at the 2 . To convert F , to C is easy and can be done in your head . From C to F . double and add 30 . So 6 c would be 6 x2 = 12 and add 30 , 42 f . To go the other way 70 F. minus 30 = 40 and divide by 2, = 20 c
10 on the inner ring is what multiplication and division hinge around. To multiply 2 x 2, line up 2 (20, really) on the outer ring opposite 10 on the inner ring. Then find 2 on the inner ring (again, use 20). Your answer will be on the outer ring, opposite 20 on the inner ring, which is 40. You have to keep track of the decimals and zeros in your head. To divide, line up the two numbers you're dividing on the outer and inner rings. The answer is opposite 10 on the inner ring. For example, to divide 90 by 3, line up 90 on the outer ring and 30 on the inner ring. Your answer is opposite the spot where 10 sits on the inner ring. You'll see that it's 30. Then you have to think about it and know that your answer must be a two digit number and 30 is the correct answer.
There are way better use for this slide rule. For example if you line the 12 up at the top you’ll notice 90 is above 45, 70 is above 35 and 50 is over 25. It’s a quick way to do halves or doubles. If you rotate it to 24 you get 16 over 40, 40 over 10 and 60 over 15 so it’s quarters or a multiplier of four. If you want to use it for quick math…
@schitlipz ... (316) instead of 10 you can find that other root value. This is a curious thing I've never noticed in any math class. Does anybody know why there are two roots depending on decimal place? It's not as simple as "even roots having two values". It must have something to do with the numerical base... perhaps. Ideas?
I mentioned it briefly in the video but the outer rings have a conversion marker for kilometers. For rate-time-distance calculations on the inner ring, any time-related unit of measurement will work: mph, kph, gph.
As a student pilot, with a slide rule watch in my possession, I can assure you that: A) I don’t wear that watch B) Pilots don’t use slide rules C) Mastering Mental Dead Reckoning is way more satisfying than mastering how to use and depend upon a slide rule, so don’t think that by being the only pilot who knows how to use a slide rule, or being a non-pilot who can tell a pilot how to use a slide rule, that you are somehow at an advantage or are superior over anyone who doesn’t know how to use one D) What pilots really want from a watch is a large, clear and legible display. Funnily enough, the most important thing a watch can do for a pilot, is tell you the time.
This is a very good video but I don't understand what you mean by "point of origin" when you're talking about division and multiplication?? Please explain?
@nikudes Yeah, I finally understood that a little while later, but thank you anyway. I wonder why there's no "0" as point of origin though, why it would start on 10 and not on 0?
My work had found a Nighthawk WR-200. Two months later, I was still the only one questioning about it. I now own it and after seeing this video, I am so keeping this $200+ watch. Such an amazing tool in a small package.
evilbluekoala626 Good stuff. Hope you enjoy your new watch.
10 years later and I finally know how to use the slide rule on my watch. Thanks for the video.
Thanks for making this video man! I just got my first Citizen Skyhawk model JY8075-51E, and the only thing I haven't quite figured out was the slide rule. All I'd really like to use it for is basic multi/div here and there. This video made that simple. Thanks!
You're welcome! Thanks for the comment. Enjoy your new watch!
@@nikudes quick question. Since the reference point is the number "10," I assume you can't do any math with numbers less than 10? Since the scale goes from 10-99?
One of the best explained how to instructions about slide rule bezels. Thank you for sharing
This helped out so much more than the thick book that came with the watch. Well done and thanks!
this video was perfect! couldnt find anyone else explaining this!
Thank you for your help, I'm taking college algebra, & we're doing a lot with average rate of change & fuel! This will help! I have the Skyhawk Titanium.
thanks .. this helped out a lot.. after a couple of months with my watch.. Its good to finally know how to use the slide rule!
Excellent video. Thank you soooo much for helping with this watch.
No worries. I'm glad you found it helpful.
this is the best watch ever made
Great stuff, Appreciated it.
Understood and very useful.
Thanks mate. Very clear instructions. I used this to teach myself this watch. Good Karma you way buddy!
Wow! I can use my watch to cheat using it as a calculator when it's not allowed!!!!! Hahahahahahah thanks man!!!!
Great video, I actually came to see whether your slide rule was also off. It is! Both a relief and a disappointment.
Thanks--ha, yeah, bit of a disappointment but thanks for the confirmation that we're not alone. :)
Thanks I'll need to watch it many times so it sinks in .but great video man
Thanks--glad you liked it. 👍
Amazed! Kewl! Never thought this lot can be done over this simple slider. :) Thanks, really appreciate this
@schitlipz Yes there is a way to find roots. It's sort of like doing a division problem. To divide 20 by 40 for example, you'd move 20 on the outer bezel ring opposite 40 on the inner ring and read the answer opposite 10 on the inner ring: 50 (meaning 0.5 because you have to figure the decimals out on your own). But you want the square root, meaning the condition in which both multipliers are equal.
Thanks for the video, it helps out a lot! you are smart!
You're welcome! Glad it helped!
Nice demo, I was curious to see what citizen added in their slide rule. I wonder how many watch owners even know that is a thing. :)
Thanks!
@negolatak I refer to the number 10 on the inner ring as the "point of origin" because that's where one starts counting numbers. It's the equivalent of zero. It just means that if you divide any number on the outer ring by the one underneath it on the inner ring, you can find your answer on the outer ring opposite the point of origin (which is the number 10 on the inner ring). Does that make sense?
Very good video, Thanks for you help.
Really good video, helped a lot!
I can finally use an e6b, thanks!
Sure thing!
I have an Omega Speedmaster Pro, a Skyhawk and two Skyhawk AT. Ithanks for your video.
very informative video, thanks for posting
Thanks, Jason. Glad you liked it. Weird that Citizen took the hour markings off.
@nikudes So to find the root of 20 turn the bezel until the number opposite 20 on the outer ring, and opposite 10 on the inner ring, are the same. In this case that's about 45 (meaning 4.5). The square of 20 is actually about 4.47.
Thanks, I found only this video for EB6! It is useful, I have C460 but I had looked for explainition a couple years ago. But sadly I leave in europe, and we counting in liter and kilometers.
It's OK-the same principles apply no matter which units you use.
is there an easier way to figure out square rooted on a Citizen Skyhawk A-T. If so I would really like to know how.
the speed your using is MPH, but worldwide aircraft speed is usually measure in KNOTS or Nautical Miles/hour ? so how do i measure the rate/time/distance if i want to use KNOTS then ?
Very well done!
BEST VIDEO!!!
Thanks for your reply. Can you do rate/time with the simple slide rule, or do you need the inner ring? Thanks again!
Thank you, this was very informative!
You can also use it to estimate square roots.
@Crashtruk2 You're welcome. Glad it helped. Thanks for the Karma wishes!
@nakmos14 It really should be "units/hour." You can use any units you want, e.g. mph, knots, kph, gallons/hour, liters/hour, and the calculations will still work. Try it out.
thanks very much. i always wondered how this works.
no i have a pilots watch myself and use it this way for fun^^
Thanks for posting- Great video! Can you recommend an inexpensive watch that can do the rate/time conversions? All I can find are the 2 ring slide rules for $100 + Thanks!
@Karlaaa94 This is model was only available in Japan, as far as I know. There are some US models that don't have the arrows. Try searching for model JR3060-59F or JY0005-50E. Good luck.
really helpful! thankyou!
The one on the left is a 24 hr. hand for local time. The one on the right shows hours and minutes for UTC time, also on a 24 hour dial. UTC is Universal Coordinated Time, sometimes called Greenwich Mean Time. It's the time at the 0˚ meridian near London.
Thanks for the feedback you guys...
@nikudes Yeah, I was messing around with the root thing and figured the "fine-tuning" thing. It's not particularly helpful because because finding two similar numbers at different parts on the bezel isn't a quick operation. Also, more importantly, square roots (or third, fourth, etc) have two values depending on the decimal position. Example: root of 7 and 700 are numerically the same, 70 and 7000 too, though different. I'm not sure why, but if you read the value at root 10 ie 3.16
Brother kindly make a video on adjusting and setting up the watch i have bought my first ecodrive it is c650 which is quite smiliar to yours i tried my ass off but i dont have any idea what is going on i tried watching videos reading manuals but nothing seems to work in my case it would be nice if you could help somehow.
Thanks, glad to hear it was helpful.
@bestvidsdottk Most slide rule bezels, this one included, have marks on one of the rings for simple conversions like this. In this case you'd line up 12 (remove a zero) on the mark labeled "STAT.," which stands for "statute miles." Opposite the mark labeled "KM." (for kilometers) you'd read off the number, in this case about 19.3. Move the decimal over one to the right (basically the opposite of what you did before) and you end up with 193, so 193 kph.
Well done
What are the two little dials in there used for?
The top 2 dials
Citizen eco drive sky hawk? :-
1) Which colour is the watch light?
2) What is the reason for night light showing red colour?
3) Does it automatically change 1 hour forward or backward automatically without manually setting?
I think it was called the Navihawk 2000GT. It was a Japan-only model.
The watch lights up blue-green.
To change from daylight savings time each time zone needs to be adjusted manually but it's fairly quick to do.
Which red light are you referring to?
very helpful thank you!
awesome video! thank you so much for teaching this! I'm a little disappointed with Citizen. I think that rate time/ distance feature is the coolest. I have the Blue Angels edition of the nighthawk and they removed the hour markings from the inner bezel. You'd think a high quality aviation watch would be sure to have that, =( thanks for making the video though :-)
@bestvidsdottk You can also do it using the multiplication method I describe in the video but then you have to know the conversion factor between mph and kph, which is about 1.6. So 120 mph x 1.6 = about 192 kph. So I was a little off in reading the bezel in my earlier reply.
What if you want to convert 120 mph to kph? Is it possible? I tried substituting a zero in the 120 and it didnt work.
Doing rate/time/distance calculations with a normal slide rule would be just like using a calculator. You'll get time in decimals (2.5 hours, for example). Search online for an E6B flight computer. It's like a slide rule but it has a time ring. They're about $25. That might be just what you're looking for.
I have a skyhawk and it sais WR 200, does that mean i can go underwater up to 660 feet?
great vid, thanks !
Is your battery fresh? The only time I've noticed that the LCD is difficult to read is when the battery is getting weak.
@BrianTakesValium No, but those ratings can be confusing. Look up "diving watch" on Wikipedia. The section called "Water Resistance Classification" should clear things up.
Inaccurate to say the least. My God, 3*3 is a tad greater than 9. And the manual has some bad translation on finding roots (very bad translation).
I've got a titanium btw.
In any case, do you know if roots can be found using this exact similar bezel or is it a page they should have left out of the manual? Thanks in advance, bro.
Wow. In one week I've found half dozen ways this watch could be better.
I love my skyhawk to, but it seems that the digital display is bad to see when the watch is tipped forward. Even tough this is an unnatural arm movement, even looking straight at it, it is less visible then when you tip it backwards. Or is that just my skyhawk?
Does the led illuminate?
@negolatak I'm not sure. Slide rules usually start on 1. you could think of 10 as 1.0 and 11 as 1.1 because the decimal point depends on how you define the numbers. But why no zero? I don't know. You'll have to ask someone better at math than I am.
Do pilots actually use this while flying or is everything computerized now?
I'm not a pilot so I'm not sure but I have heard of analog flight computers (from what I understand, they're a bigger version of a rotating slide rule on this watch). I think the watches were just meant as back-ups.
Nicely done. I have 2 questions. Is the point of origin always 10? Can you convert F degrees to C degrees for temperature?
Thank you.
+Time4achange Thanks. 10 is the origin for multiplication and division. The yellow arrow at the top of the inner ring is the origin for rate/time/distance calculations.
Fahrenheit to Celsius is a little trickier. If the conversion points were on the bezel that would be easy but I don't think they are. The formula is °C = (°F - 32) / 1.8, so you'd take your ˚F number, subtract 32 (in your head), and divide the result by 1.8, that is, find your result on the outer ring, then spin it until it's opposite 18 on the inner ring (that's the 1.8) and then read the result opposite 10 on the inner ring (your origin).
I'm not sure what you mean by starting at 10 . You may start anywhere , depending on the calculation you are doing . if for example multiplying 2 by 2 ,start at the 2 . To convert F , to C is easy and can be done in your head . From C to F . double and add 30 . So 6 c would be 6 x2 = 12 and add 30 , 42 f . To go the other way 70 F. minus 30 = 40 and divide by 2, = 20 c
10 on the inner ring is what multiplication and division hinge around. To multiply 2 x 2, line up 2 (20, really) on the outer ring opposite 10 on the inner ring. Then find 2 on the inner ring (again, use 20). Your answer will be on the outer ring, opposite 20 on the inner ring, which is 40. You have to keep track of the decimals and zeros in your head. To divide, line up the two numbers you're dividing on the outer and inner rings. The answer is opposite 10 on the inner ring. For example, to divide 90 by 3, line up 90 on the outer ring and 30 on the inner ring. Your answer is opposite the spot where 10 sits on the inner ring. You'll see that it's 30. Then you have to think about it and know that your answer must be a two digit number and 30 is the correct answer.
No worries! Thanks!
There are way better use for this slide rule. For example if you line the 12 up at the top you’ll notice 90 is above 45, 70 is above 35 and 50 is over 25. It’s a quick way to do halves or doubles. If you rotate it to 24 you get 16 over 40, 40 over 10 and 60 over 15 so it’s quarters or a multiplier of four. If you want to use it for quick math…
Yes, it does.
THANK YOU
@schitlipz ... (316) instead of 10 you can find that other root value. This is a curious thing I've never noticed in any math class.
Does anybody know why there are two roots depending on decimal place? It's not as simple as "even roots having two values". It must have something to do with the numerical base... perhaps. Ideas?
Thanks!
Thanks for not saying...like and subscribe.
Nice
@g7895718 Cool! Nice to hear. Glad the video helped.
Can you convert km h to mph with it?
Yes--that and other conversion factors are located on the outer bezel ring.
ah yes I see, you line up stat or naut miles and then read the value where km is pointing to, thanks @@nikudes
@Karlaaa94 There are lots on the market now that don't have yellow pointers. Check out Princeton Watches online for example. They've got a bunch.
How do i used in tearms of KM
I mentioned it briefly in the video but the outer rings have a conversion marker for kilometers. For rate-time-distance calculations on the inner ring, any time-related unit of measurement will work: mph, kph, gph.
I wish I knew how to use this in grade school
@nikudes thanks
@nikudes thanks!!!
🤯
nice vid but i think i will stick to my Pooleys - CRP-5 Computer
All I can think of is a calculator watch. Of course, then you get decimals versions of time. Sorry I couldn't be of more help.
As a student pilot, with a slide rule watch in my possession, I can assure you that:
A) I don’t wear that watch
B) Pilots don’t use slide rules
C) Mastering Mental Dead Reckoning is way more satisfying than mastering how to use and depend upon a slide rule, so don’t think that by being the only pilot who knows how to use a slide rule, or being a non-pilot who can tell a pilot how to use a slide rule, that you are somehow at an advantage or are superior over anyone who doesn’t know how to use one
D) What pilots really want from a watch is a large, clear and legible display. Funnily enough, the most important thing a watch can do for a pilot, is tell you the time.
My horse doesn't use fuel and he runs 10 mph. Only. 🤔
In that case you could calculate oats per hour. ;)
ROFL!! 9x9 =81
Gh
He's doing it all wrong don't listen to this guy
This is a very good video but I don't understand what you mean by "point of origin" when you're talking about division and multiplication?? Please explain?
@nikudes Yeah, I finally understood that a little while later, but thank you anyway. I wonder why there's no "0" as point of origin though, why it would start on 10 and not on 0?
Very helpful. Thankyou. 👍