Question

[songar87]

Does anyone know how, in "The Pegasus Project", they get a Milky Way gate to dial another Mily Way gate from the Pegasus galaxy? (Reprograming Milky Way symbols with Pegasus symbols, maybe?)

[2ndgenerationalteran]

effects of time dialation caused by the black hole, i think it was mentioned twice once by mcay and once by mitchell

[Tanith]

And by the way, where did they get the gate used to dial the supergate? For now, I assume that it is a reprogramed Milky Way gate, seeing as how it phisycally spins (unlike othe gates in Pegasus)

The gate they took to Pegasus was a Milky Way gate, it had orange chevrons and as you said, it spins when dialled.

[gopher65]

No he's right. In addition to the temporal dilation (off the top of my head I'm uncertain how to calculate the severity of that. I guess I could look it up.), the red-shifting of the radio signal should have made Teal'c's (that just looks weird with 2 apostrophes) voice slower, but the opposite should have happened to Carter's voice due to blue-shifting. This is assuming they were using an analog signal. I don't know whether a digital signal would have had the same thing happen, or if the computer would have been forced to store it and play it back in chunks at regular speed.

In either case, and, in fact, with the temporal dilation as well, the computer should have just buffered the message and adjusted it to play at normal speed.

In fact, now that I think about it, Teal'c was the one with time slowed down. So the dilation would have acted with the blue-shift to speed up her voice. She should have sounded like a chipmunk to Teal'c, since from his reference frame, she would have been moving faster.

[Zatnikitelman]

Dialation should acton BOTH ends as the black hole will affect the radio transmission heading into the 'Gate and coming back out. Even a digital signal has to have an analog carrier wave, it's basic physics! It's not the modulation, but the frequency that matters SHEESH!

[gopher65]

Because of the effects of the wormhole, Teal'c was much "closer" to the blackhole than Carter was. So he should have been going slower (and he was). But she should have been going faster (and she wasn't, she was going slow too).

[gopher65]

Dialation should acton BOTH ends as the black hole will affect the radio transmission heading into the 'Gate and coming back out. Even a digital signal has to have an analog carrier wave, it's basic physics! It's not the modulation, but the frequency that matters SHEESH!

And I have no idea what you mean with most of this paragraph.

A digital signal is carried on an analog signal, but while an analog signal is just played back, a digital signal is analyzed at certain points ("sampled"). I was thinking that if these points didn't correspond to a known decoding... thing (can't think of the word)... the computer might not play back the message. But I guess they'd just have to use some autocorrelation software to match the frequency stretch. Whether or not they'd have to (very easily) write a new program, or whether current software could do it, I do not know. I still don't understand why they didn't just resample the message and play it back at normal speed though. How hard would that have been? (Course then we wouldn't have got a cool sound effect.)

Regardless, I'm pretty sure the gravity would red/blue shift the frequency of the carrier wave, depending on who was sending it (remember, Teal'c is "closer" to the black hole for most of the episode due to his proximity to the Stargate). And unless they are using an AM carrier wave, the frequency is what would matter. That seems unlikely because FM carrier waves are better at overcoming noise, which would be a good thing if you were near an active black hole, with all that radiation around you. If they are using an AM wave, then I don't think the red/blue shift would matter at all.

[Tanis]

I have another question about "The Pegasus Project" episode:

The SG1 team takes a Stargate to a black hole of the Galaxy Pegasus.

My question is: Where they take this Stargate? This Stargate is from Earth? The how many Stargates has SCG? Or perhaps this Stargate were stolen?

[HAL]

It was from the stash of stargates they took from baal

[gopher65]

It was from the stash of stargates they took from baal

Hehe yeah, they have dozens now! Though, if it were me I'd be trying to restore most of them to their worlds so that I could get there by stargate (keep a few in reserve).

[Zatnikitelman]

And I have no idea what you mean with most of this paragraph.

A digital signal is carried on an analog signal, but while an analog signal is just played back, a digital signal is analyzed at certain points ("sampled"). I was thinking that if these points didn't correspond to a known decoding... thing (can't think of the word)... the computer might not play back the message. But I guess they'd just have to use some autocorrelation software to match the frequency stretch. Whether or not they'd have to (very easily) write a new program, or whether current software could do it, I do not know. I still don't understand why they didn't just resample the message and play it back at normal speed though. How hard would that have been? (Course then we wouldn't have got a cool sound effect.)

Regardless, I'm pretty sure the gravity would red/blue shift the frequency of the carrier wave, depending on who was sending it (remember, Teal'c is "closer" to the black hole for most of the episode due to his proximity to the Stargate). And unless they are using an AM carrier wave, the frequency is what would matter. That seems unlikely because FM carrier waves are better at overcoming noise, which would be a good thing if you were near an active black hole, with all that radiation around you. If they are using an AM wave, then I don't think the red/blue shift would matter at all.

And I'm not sure what you mean by this paragraphs. Even if it is digital, the modulation will shift, it's called the doppler effect, it works on radio waves with gravity just like with a moving object. The sampling would be longer. I've done this with the open source audacity. Change the sampling rate, change the received pitch.

[gopher65]

And I'm not sure what you mean by this paragraphs. Even if it is digital, the modulation will shift, it's called the doppler effect, it works on radio waves with gravity just like with a moving object. The sampling would be longer. I've done this with the open source audacity. Change the sampling rate, change the received pitch.

The frequency will shift, not the Amplitude. Amplitude will stay the same.

EDIT: You had me doubting myself, so I looked it up:
http://en.wikipedia.org/wiki/Doppler_effect
EDIT2:
FM = Frequency Modulation
AM = Amplitude Modulation

Frequency gets shifted, amplitude does not. So FM signals would be affected, AM signals would not be. That's what I was trying to say.

[Zatnikitelman]

I'd suggest you not argue with me because I had to study this stuff to get a federal license. The modulation has zip effect on the outcome for the most part. Yes, the amplitude will remain the same, but the frequency will not. If you take an AM wave and squish it up, it will be a higher pitch, if you do the same with FM it will still be a higher pitch.

[gopher65]

Yes, the amplitude will remain the same, but the frequency will not.

Are you even reading my posts? That's what I said. 3 times. Then you go and say "nuh uh". Or at least I think you do. Your lack of proper grammar makes your posts really hard to understand, so I'm never entirely certain what you are talking about (not singling you out. Most of the people on every forum (including this one) suffer from this problem. Well, actually, most of the people in real life do to. I mean, it's not like I expect people to spend hours picking out every little error in their writing. We all have little errors that slip through a quick proofread. But I expect people not to write like they're grade 4 students. Grrr. I blame the teachers.).

[Zatnikitelman]

Your saying that AM won't be affected because it is modulating the amplitude or is the lack of proper grammer not allowing me to see what you really mean? (There, we're both even in the grammar jabing department.)
What I'm saying is that no matter the modulation of the carrier wave, the received signal will be noticably doppler shifted. Due to the radio wave travelling close to the blackhole going both directions, the effect is noticed on both ends. AM will be affected along with FM and PM as the sampling of the digital signal will be different. I can take an audio sample in Audacity, run it at say 44k Hz, then redo it to sample at say 22k Hz and it will be noticeably lower in pitch.