network profile
| bio | website | shikadi.net |
|---|---|---|
| location | Brisbane, Australia | |
| age | ||
| visits | member for | 3 years, 3 months |
| seen | Mar 16 at 21:23 | |
| stats | profile views | 47 |
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Mar 12 |
awarded | Commentator |
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Mar 12 |
accepted | Is information lost when you downconvert an RF frequency? |
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Mar 12 |
comment |
Is information lost when you downconvert an RF frequency? Right, this makes perfect sense now I realise that turning a carrier completely on and off, even only at the zero point, is still the same as modulating it. Thanks for the detailed explanation! |
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Mar 12 |
comment |
Is information lost when you downconvert an RF frequency? Ahh, I think this is what I missed - that turning a carrier on and off is no different to modulating it with a lower frequency. Now I understand! Thanks! |
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Mar 12 |
asked | Is information lost when you downconvert an RF frequency? |
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Oct 11 |
awarded | Nice Question |
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Sep 9 |
accepted | Can somebody explain what IQ (quadrature) means in terms of SDR? |
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Sep 9 |
comment |
Can somebody explain what IQ (quadrature) means in terms of SDR? Thanks! Unfortunately there's still a little bit of hand-waving going on :-) So do you mean if you 'heterodyne' on the software side, to put your target signal at baseband, that's where you need both I and Q? Why do the sidebands get folded? Is it because one sideband ends up being shifted to a negative frequency, which then appears as a positive frequency with a phase shift, cancelling out the other sideband? Maybe this explains why I've read things about the I and Q signals sometimes having imaginary components. |
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Sep 8 |
comment |
Can somebody explain what IQ (quadrature) means in terms of SDR? Thanks for the explanation, but I'm still a little unclear. How do you "sample a signal 90 degrees out of phase"? Do you mean a second sample is taken, delayed by some amount of time? How does having I and Q allow you to measure the relative phase, as opposed to looking at a few previous samples to see which way the waveform is going? What do you mean by "preserving the phase relationship through the conversion"? What happens if the phase relationship is not preserved? And does heterodyning a single signal cause this? |
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Sep 8 |
asked | Can somebody explain what IQ (quadrature) means in terms of SDR? |
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May 31 |
awarded | Popular Question |
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Feb 18 |
awarded | Yearling |
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Jul 30 |
comment |
Can't get DS1077 programmable oscillator to work @jajomafa: Unfortunately I'm still not sure what I did, but I had some other I2C devices connected at the time which I suspect may have been interfering. I tried programming the DS1077 separately (out of circuit) and then connecting it up and that seemed to do the trick, although there was still a bit of trial and error getting the frequency I set to take hold. |
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Mar 19 |
awarded | Yearling |
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Feb 26 |
comment |
What kind of spade connector is this? Thanks for the response, I ended up getting a spade connector of the given width and this did indeed fit and works well. It seems the weirdness of this connector was simply to make it easy to connect and disconnect - you can push in on the middle part to slide it off with no effort at all, and indeed the plastic cover does this for you when you try to pull it away from the connector. |
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Feb 26 |
accepted | What kind of spade connector is this? |
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Feb 6 |
awarded | Editor |
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Feb 6 |
revised |
What kind of spade connector is this? Figured out how to remove plastic cover, added more images |
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Feb 6 |
asked | What kind of spade connector is this? |
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Mar 27 |
comment |
What is the purpose of a bias resistor? I've just been working with an IC that does this, now I understand why! But how do you "undo" the bias at the other end to move the signal back to +V/-V? |
