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Posted: 11/3/2009 7:01:29 AM EST
[Last Edit: 11/3/2009 7:02:53 AM EST by GaryM]
with your radio on listening to some killer jams while flying at 10,000 mph toward the radio station transmitter would you have to adjust the frequency of the radio once you flew past the transmitting antenna?
Link Posted: 11/3/2009 7:03:10 AM EST

Originally Posted By GaryM:
with your radio on listening to some killer jams while flying at 10,000 mph toward the radio station transmitter would you have to adjust the frequency pf the radio once you flew past the transmitting antenna?

10K/hr compared to 186K/s, the electronics could compensate.
Link Posted: 11/3/2009 7:04:37 AM EST
PLL or superhet radio?
Link Posted: 11/3/2009 7:04:44 AM EST
I would be too impressed that the airplane could fly at 10,000mph to even hear my killer jams.
Link Posted: 11/3/2009 7:08:29 AM EST

Originally Posted By ZeroZero:
I would be too impressed that the airplane could fly at 10,000mph to even hear my killer jams.

Well, it IS possible in a certain "plane". Yeah, it flies.
Link Posted: 11/3/2009 7:11:18 AM EST
Originally Posted By Keith_J:

Originally Posted By ZeroZero:
I would be too impressed that the airplane could fly at 10,000mph to even hear my killer jams.

Well, it IS possible in a certain "plane". Yeah, it flies.


Not sure if I should say "OPSEC" or "hide your dog."

Link Posted: 11/3/2009 7:20:47 AM EST
Link Posted: 11/3/2009 7:21:29 AM EST

Originally Posted By Keith_J:
PLL or superhet radio?

OP scratches head......

Link Posted: 11/3/2009 7:22:41 AM EST
Originally Posted By DoubleFeed:

Originally Posted By doggscube:
Originally Posted By Keith_J:

Originally Posted By ZeroZero:
I would be too impressed that the airplane could fly at 10,000mph to even hear my killer jams.

Well, it IS possible in a certain "plane". Yeah, it flies.


Not sure if I should say "OPSEC" or "hide your dog."

I think he's talking about the Space Shuttle.



We have a winnah!
Link Posted: 11/3/2009 7:24:55 AM EST
Originally Posted By GaryM:
with your radio on listening to some killer jams while flying at 10,000 mph toward the radio station transmitter would you have to adjust the frequency of the radio once you flew past the transmitting antenna?



FAIL. Scenario lacks treadmill reference.
Link Posted: 11/3/2009 7:25:59 AM EST
Link Posted: 11/3/2009 7:26:28 AM EST
Originally Posted By goldtop:
Originally Posted By DoubleFeed:

Originally Posted By doggscube:
Originally Posted By Keith_J:

Originally Posted By ZeroZero:
I would be too impressed that the airplane could fly at 10,000mph to even hear my killer jams.

Well, it IS possible in a certain "plane". Yeah, it flies.


Not sure if I should say "OPSEC" or "hide your dog."

I think he's talking about the Space Shuttle.



We have a winnah!


Gotta rock out while door-gunning!
Link Posted: 11/3/2009 7:28:04 AM EST
Hmmm...is it even legal to listen to AM/FM radio while on a plane? My .mp3 player goes with my on plane trips, and has a radio I rarely use....


(seems like you'd need to change stations every 10 minutes, though...)

Link Posted: 11/3/2009 7:30:01 AM EST
Assuming you mean the doppler shift would change the frequency, probably not enough to notice considering the 183,000 miles
per SECOND velocity of the RF signal.
Link Posted: 11/3/2009 7:33:17 AM EST
Link Posted: 11/3/2009 7:41:19 AM EST
I can tell you that at 850 knots ground speed the answer is no.
Link Posted: 11/3/2009 7:45:08 AM EST
Actually, I don't think 10k MPH would be enough to induce any noticeable effect.
Link Posted: 11/3/2009 7:46:04 AM EST
Originally Posted By AeroE:
If the reciever needs compensation after passage, it needed compensation as the distance decreased while approaching.

10000 mph is 4.5 kilometers per second.



Which is about a 10 ppm frequency shift. I would assume that could be significant, depending on the radio.
Link Posted: 11/3/2009 7:53:50 AM EST
If yer ADF is actually working, YES.

But at that speed in a Cessna 172, the wings would melt. And soon thereafter the engine, radio's and pilot....
Link Posted: 11/3/2009 7:55:54 AM EST
So far, it appears that everyone has it WRONG (unless I missed a post). Ham radio operators use satellites to talk to each other all of the time. To maintain a clear signal, you do have to adjust the frequency to compensate for Doppler shift as the bird passes overhead.


Link Posted: 11/3/2009 7:56:53 AM EST
how fast do LEO sats move?


I don't know but you do adjust for Doppler shift with them- TX and RX

Link Posted: 11/3/2009 8:55:21 AM EST
[Last Edit: 11/3/2009 8:56:17 AM EST by GaryM]
Originally Posted By Keith_J:
PLL or superhet radio?


Sony with CD player. Oh, and sirius capable.

Oh, cargo plane carry a load of treadmills for all the starving children in Africa.
Link Posted: 11/3/2009 8:57:16 AM EST

Originally Posted By GaryM:
Originally Posted By Keith_J:
PLL or superhet radio?


Sony with CD player. Oh, and sirius capable.

Oh, cargo plane carry a load of treadmills for all the starving children in Africa.

Only cargo planes don't go 10k MPH.

Link Posted: 11/3/2009 9:00:42 AM EST
Originally Posted By DoubleFeed:

Originally Posted By doggscube:
Originally Posted By Keith_J:

Originally Posted By ZeroZero:
I would be too impressed that the airplane could fly at 10,000mph to even hear my killer jams.

Well, it IS possible in a certain "plane". Yeah, it flies.


Not sure if I should say "OPSEC" or "hide your dog."

I think he's talking about the Space Shuttle.



In which case I wouldn't be able to hear my radio over the sound of me going WOOOOOOOOO! THIS IS AWESOME11i'M ON THE MOTHERFUCKING SPAAACE SHUTTLLLLE BITCHES!!!!!!!
Link Posted: 11/3/2009 9:01:58 AM EST
Originally Posted By Keith_J:

Originally Posted By GaryM:
Originally Posted By Keith_J:
PLL or superhet radio?


Sony with CD player. Oh, and sirius capable.

Oh, cargo plane carry a load of treadmills for all the starving children in Africa.

Only cargo planes don't go 10k MPH.



you have to set all the treadmills in the hold to "10".
Link Posted: 11/3/2009 9:08:21 AM EST
Originally Posted By DoubleFeed:

Originally Posted By doggscube:
Originally Posted By Keith_J:

Originally Posted By ZeroZero:
I would be too impressed that the airplane could fly at 10,000mph to even hear my killer jams.

Well, it IS possible in a certain "plane". Yeah, it flies.


Not sure if I should say "OPSEC" or "hide your dog."

I think he's talking about the Space Shuttle.



I didn't think of that, I went with the "super-secret pulse-jet plane" angle.
Link Posted: 11/3/2009 10:15:22 AM EST
Then again what is the space shuttle it not a cargo plane?

Do they have shuttle landing strips in africa?
Link Posted: 11/3/2009 10:24:23 AM EST
[Last Edit: 11/3/2009 10:25:11 AM EST by AeroE]
Link Posted: 11/3/2009 10:25:50 AM EST
Link Posted: 11/3/2009 10:29:17 AM EST
[Last Edit: 11/3/2009 10:34:49 AM EST by Greenhorn]
Originally Posted By GaryM:
with your radio on listening to some killer jams while flying at 10,000 mph toward the radio station transmitter would you have to adjust the frequency of the radio once you flew past the transmitting antenna?


It would be like walking at 1/4" per second and expecting the pitch of sound to change.

186,000m/s / 2.77m/s = about 67,000, so 10,000mph is 1/67,000th the speed of light.

Divide the speed of sound (~800mph) by 67,000 and you get 0.012mph, or about .017fps
Link Posted: 11/3/2009 10:35:36 AM EST
Originally Posted By Greenhorn:
Originally Posted By GaryM:
with your radio on listening to some killer jams while flying at 10,000 mph toward the radio station transmitter would you have to adjust the frequency of the radio once you flew past the transmitting antenna?


It would be like walking at 1/8" per second and expecting the pitch of sound to change.


The pitch WOULD change. Whether or not that change is significant depends on the instrumentation, and what the signal is being used for.
Link Posted: 11/3/2009 2:09:49 PM EST
[Last Edit: 11/3/2009 2:11:11 PM EST by Greenhorn]
Originally Posted By AR4U:
Originally Posted By Greenhorn:
Originally Posted By GaryM:
with your radio on listening to some killer jams while flying at 10,000 mph toward the radio station transmitter would you have to adjust the frequency of the radio once you flew past the transmitting antenna?


It would be like walking at 1/8" per second and expecting the pitch of sound to change.


The pitch WOULD change. Whether or not that change is significant depends on the instrumentation, and what the signal is being used for.


You would need some EXTREMELY sensitive equipment to detect a difference. Walking toward a source of the pitch A-440 at 1/4" per second would change the pitch by something like .05 of a cent, or 1/2000th of a semitone (rough math, using linear math rather than exponential, but it's somewhere right around there). No musician in the world could hear that. Perhaps a very, very sensitive machine could hear the difference.
Link Posted: 11/3/2009 2:21:57 PM EST
Originally Posted By GaryM:
Then again what is the space shuttle it not a cargo plane?

Do they have shuttle landing strips in africa?


Hoedspruit, South Africa

http://www.globalsecurity.org/space/facility/sts-els.htm
Link Posted: 11/3/2009 2:43:46 PM EST

Originally Posted By Dr_Dickie:

Originally Posted By GaryM:
with your radio on listening to some killer jams while flying at 10,000 mph toward the radio station transmitter would you have to adjust the frequency pf the radio once you flew past the transmitting antenna?

10K/hr compared to 186K/s, the electronics could compensate.

Agree with this. But not this.

You wouldn't notice the compression / decompression similar to the Doppler effect for sound waves.

Now if you were traveling closer to the speed of light, then a compression similar to blue-shifting or red-shifting of light might occur.

But it would not compress / decompress the sound transmitted by the radio waves, it would change the frequency of those radio waves and therefore your radio channel would change.
Link Posted: 11/3/2009 2:55:44 PM EST

Originally Posted By AeroE:
Why do you want to know? Is the USPS planning to buy surplus shuttles for hauling the mail?

I can see it now; cargo door failure causes a night of bright, but short, meteors from re-entering mail bags.

Also, the USPS does not need door gunners.


Link Posted: 11/3/2009 8:07:57 PM EST
Originally Posted By AeroE:

Also, the USPS does not need door gunners.


Well damn, there go my career plans....
Link Posted: 11/4/2009 2:56:35 AM EST
Link Posted: 11/4/2009 5:57:09 AM EST
Although a Doplar effect would occur it would be too small to be noticed.
Link Posted: 11/4/2009 6:22:41 AM EST
.....and this would matter for......

How many seconds would you be able to receive a signal from a FM radio station with a... 100 mile signal radius?

......at 10,000mph?

36 seconds?


Use the CD player
Link Posted: 11/4/2009 11:01:00 AM EST
Originally Posted By Greenhorn:
Originally Posted By AR4U:
Originally Posted By Greenhorn:
Originally Posted By GaryM:
with your radio on listening to some killer jams while flying at 10,000 mph toward the radio station transmitter would you have to adjust the frequency of the radio once you flew past the transmitting antenna?


It would be like walking at 1/8" per second and expecting the pitch of sound to change.


The pitch WOULD change. Whether or not that change is significant depends on the instrumentation, and what the signal is being used for.


You would need some EXTREMELY sensitive equipment to detect a difference. Walking toward a source of the pitch A-440 at 1/4" per second would change the pitch by something like .05 of a cent, or 1/2000th of a semitone (rough math, using linear math rather than exponential, but it's somewhere right around there). No musician in the world could hear that. Perhaps a very, very sensitive machine could hear the difference.


Frequency counter would detect it easily. If the frequency of the crystal oscillator I use as a microbalance shifted 1/10th as much as that, it would be totally useless. Remember, the sound/pitch was your analogy. We're talking about a radio, and shifts in it's carrier frequency. I can't imagine that wouldn't screw with a Frequency Modulated signal.
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