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#4060
by
WarpTech
on 29 Jul, 2016 22:20
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New ADC arrived. HUGE improvement in resolution of the data. These are two-minute unpowered tests with CPU fan going in the room - which I did on purpose so there would be a little movement. Top image is with the new ADC, bottom image is with the old one. Settings are the same. Flattened areas are completely gone. 
I am using the 20 µm setting on the LDS for these runs, so I should be able to squeeze out even more resolution using the 3 µm setting!
Looks awesome now! Throw the darn switch already! LOL!
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#4061
by
Monomorphic
on 30 Jul, 2016 01:54
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Getting ready to throw the switch on the wedge. Most of today was spent integrating the new ADC, balancing, and tuning. Center is 2.452Ghz. Here are the latest images.
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#4062
by
RERT
on 30 Jul, 2016 15:15
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If my number for the drag of 30-230 micronewton is correct, and if they use only 12 watts, that's about 2.4 - 18.4 milli-Newton per kilowatt. Doesn't sound wild compared to other numbers, unless my memory is playing tricks.
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#4063
by
zen-in
on 30 Jul, 2016 18:14
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New ADC arrived. HUGE improvement in resolution of the data. These are two-minute unpowered tests with CPU fan going in the room - which I did on purpose so there would be a little movement. Top image is with the new ADC, bottom image is with the old one. Settings are the same. Flattened areas are completely gone.
I am using the 20 µm setting on the LDS for these runs, so I should be able to squeeze out even more resolution using the 3 µm setting!
It looks like there were a lot of problems with the old A/D. It is impossible to say what the problems were without more information. You have that problem solved now so there is no need to look back.
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#4064
by
Monomorphic
on 30 Jul, 2016 19:30
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First powered test with the TE203 wedge. I'm getting the same "reverse thrust" as seen with the TE311 frustum.
Nothing has changed on the build except for the resonator itself. I even moved the entire test stand two feet further away from the masonry wall as it likely contains ferromagnetic rebar. I double-checked to make sure that less voltage in the graph is "reverse" (big end leading). I've performed two powered test now with very similar results.
One note: My magnetron is nearing its end. I can tell by not only the sound it makes, but also by watching the signal in the spectrum analyser. I may run to walmart and pick up a new one or order the same version I have from amazon.
EDIT: The files attached to this post were incorrect. Please see post below for explanation and correct versions:
http://forum.nasaspaceflight.com/index.php?topic=39772.msg1564917#msg1564917
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#4065
by
rfmwguy
on 30 Jul, 2016 20:13
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First powered test with the TE203 wedge. I'm getting the same "reverse thrust" as seen with the TE311 frustum.
Nothing has changed on the build except for the resonator itself. I even moved the entire test stand two feet further away from the masonry wall as it likely contains ferromagnetic rebar. I double-checked to make sure that less voltage in the graph is "reverse" (big end leading). I've performed two powered test now with very similar results.
One note: My magnetron is nearing its end. I can tell by not only the sound it makes, but also by watching the signal in the spectrum analyser. I may run to walmart and pick up a new one or order the same version I have from amazon.
Like the way you've set the range area as power on for about 1.5 minutes. Interested in knowing how the Frequencies were overlaid on the chart. Was it logging ctr on the spec an and filling them in?
Also, appears thermal is upwards on the chart and it only takes over after power off condition. This is significant. In a way, this mimics my old teeter-totter method, where lift "ran-away" when power was off, fought against it during power on.
I am beginning to wonder if side-centered power insertion leads to displacement towards large end. Also interesting to note mode changes do not appear to have an effect on thrust direction on your 2 designs. Hmmmm...perhaps exact modes are not part of the theory of operation.
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#4066
by
SeeShells
on 30 Jul, 2016 21:22
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First powered test with the TE203 wedge. I'm getting the same "reverse thrust" as seen with the TE311 frustum.
Nothing has changed on the build except for the resonator itself. I even moved the entire test stand two feet further away from the masonry wall as it likely contains ferromagnetic rebar. I double-checked to make sure that less voltage in the graph is "reverse" (big end leading). I've performed two powered test now with very similar results.
One note: My magnetron is nearing its end. I can tell by not only the sound it makes, but also by watching the signal in the spectrum analyser. I may run to walmart and pick up a new one or order the same version I have from amazon.
Like the way you've set the range area as power on for about 1.5 minutes. Interested in knowing how the Frequencies were overlaid on the chart. Was it logging ctr on the spec an and filling them in?
Also, appears thermal is upwards on the chart and it only takes over after power off condition. This is significant. In a way, this mimics my old teeter-totter method, where lift "ran-away" when power was off, fought against it during power on.
I am beginning to wonder if side-centered power insertion leads to displacement towards large end. Also interesting to note mode changes do not appear to have an effect on thrust direction on your 2 designs. Hmmmm...perhaps exact modes are not part of the theory of operation.
I'm struggling here on the thermal effects and how they would show up on a rotational torsion pendulum. Thermal effects from the magnetron heating are vertical in nature. How could that relate to a rotational number from his ADC? It looks more like the torsion pendulum's spring action returning to 0.
Shell
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#4067
by
otlski
on 30 Jul, 2016 22:12
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I'm struggling here on the thermal effects and how they would show up on a rotational torsion pendulum. Thermal effects from the magnetron heating are vertical in nature. How could that relate to a rotational number from his ADC? It looks more like the torsion pendulum's spring action returning to 0.
Shell
As convection flow rises, air must come into the area from the bottom and side to replace the rising air. This replacement air flows up and around the bottom of the wedge. It is conceivable that the wedge will "surf" this rising wave of convection pushing the large end forward. Is this the direction of his thrust?
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#4068
by
SeeShells
on 30 Jul, 2016 22:57
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I'm struggling here on the thermal effects and how they would show up on a rotational torsion pendulum. Thermal effects from the magnetron heating are vertical in nature. How could that relate to a rotational number from his ADC? It looks more like the torsion pendulum's spring action returning to 0.
Shell
As convection flow rises, air must come into the area from the bottom and side to replace the rising air. This replacement air flows up and around the bottom of the wedge. It is conceivable that the wedge will "surf" this rising wave of convection pushing the large end forward. Is this the direction of his thrust?
It looks like he has made the bottom flat.
Shell
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#4069
by
Monomorphic
on 30 Jul, 2016 23:01
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Hold the presses! I have to manually enter the RF frequencies and power on/off based on a video I make that captures the spectrum analyser with time stamp. One was capturing my local time (which was off 10 seconds) and the other UTC. So there was a 4:01:10 difference between the two. I had not accounted for the 10 sec portion in my previous charts, so they are completely wrong.
This new chart is much more interesting, and I have double-checked it. Notice displacement as soon as RF is present and maximum displacement at peak return loss.
Will edit the post above and delete the incorrect files.
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#4070
by
SeeShells
on 30 Jul, 2016 23:18
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Hold the presses! I have to manually enter the RF frequencies and power on/off based on a video I make that captures the spectrum analyser with time stamp. One was capturing my local time (which was off 10 seconds) and the other UTC. So there was a 4:01:10 difference between the two. I had not accounted for the 10 sec portion in my previous charts, so they are completely wrong.
This new chart is much more interesting, and I have double-checked it. Notice displacement as soon as RF is present and maximum displacement at peak return loss.
Will edit the post above and delete the incorrect files.
It appears like a thrust reversal at PRL. Doesn't match the FEKO although real world versus simulation I'd expect that.
It is very interesting monomorphic.
Shell
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#4071
by
rfmwguy
on 30 Jul, 2016 23:27
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Hold the presses! I have to manually enter the RF frequencies and power on/off based on a video I make that captures the spectrum analyser with time stamp. One was capturing my local time (which was off 10 seconds) and the other UTC. So there was a 4:01:10 difference between the two. I had not accounted for the 10 sec portion in my previous charts, so they are completely wrong.
This new chart is much more interesting, and I have double-checked it. Notice displacement as soon as RF is present and maximum displacement at peak return loss.
Will edit the post above and delete the incorrect files.
There you go...perfect match on this run on peak RL. This would be where current flow heat loss would be at a minimum! Displacement is opposite that of power off which shows a deflection off center. My data shows a long persistence which I believe is thermal. IP on the other sub has a nice chart for this. I saw about 10-15 minutes before a return to center or starting point. You might try a long dataset after power off. Your're seeing what I'm seeing...nice.
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#4072
by
TheTraveller
on 31 Jul, 2016 03:09
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Hold the presses! I have to manually enter the RF frequencies and power on/off based on a video I make that captures the spectrum analyser with time stamp. One was capturing my local time (which was off 10 seconds) and the other UTC. So there was a 4:01:10 difference between the two. I had not accounted for the 10 sec portion in my previous charts, so they are completely wrong.
This new chart is much more interesting, and I have double-checked it. Notice displacement as soon as RF is present and maximum displacement at peak return loss.
Will edit the post above and delete the incorrect files.
Well done Jamie,
You just plotted your 1st frustum thrust bandwidth.
How does this thrust bandwidth plot compare as against the S11 RL bandwidth plot?
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#4073
by
zellerium
on 31 Jul, 2016 05:22
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Hold the presses! I have to manually enter the RF frequencies and power on/off based on a video I make that captures the spectrum analyser with time stamp. One was capturing my local time (which was off 10 seconds) and the other UTC. So there was a 4:01:10 difference between the two. I had not accounted for the 10 sec portion in my previous charts, so they are completely wrong.
This new chart is much more interesting, and I have double-checked it. Notice displacement as soon as RF is present and maximum displacement at peak return loss.
Will edit the post above and delete the incorrect files.
There you go...perfect match on this run on peak RL. This would be where current flow heat loss would be at a minimum! Displacement is opposite that of power off which shows a deflection off center. My data shows a long persistence which I believe is thermal. IP on the other sub has a nice chart for this. I saw about 10-15 minutes before a return to center or starting point. You might try a long dataset after power off. Your're seeing what I'm seeing...nice.
Very interesting results!!
Any idea of the magnitude of the maximum force?
Also, wouldn't peak RL also mean maximum cavity heating?
Not to say this looks completely like a thermal effect...
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#4074
by
TheTraveller
on 31 Jul, 2016 06:55
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Hold the presses! I have to manually enter the RF frequencies and power on/off based on a video I make that captures the spectrum analyser with time stamp. One was capturing my local time (which was off 10 seconds) and the other UTC. So there was a 4:01:10 difference between the two. I had not accounted for the 10 sec portion in my previous charts, so they are completely wrong.
This new chart is much more interesting, and I have double-checked it. Notice displacement as soon as RF is present and maximum displacement at peak return loss.
Will edit the post above and delete the incorrect files.
There you go...perfect match on this run on peak RL. This would be where current flow heat loss would be at a minimum! Displacement is opposite that of power off which shows a deflection off center. My data shows a long persistence which I believe is thermal. IP on the other sub has a nice chart for this. I saw about 10-15 minutes before a return to center or starting point. You might try a long dataset after power off. Your're seeing what I'm seeing...nice.
Very interesting results!!
Any idea of the magnitude of the maximum force?
Also, wouldn't peak RL also mean maximum cavity heating?
Not to say this looks completely like a thermal effect...
Max cavity heating at RL peak but also min maggie heating as min reflected power.
Likewise, max maggie heating and min cavity heating at the outside edges of the thrust curve as there is max reflected power back into the maggie.
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#4075
by
RotoSequence
on 31 Jul, 2016 12:08
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Max cavity heating at RL peak but also min maggie heating as min reflected power.
Likewise, max maggie heating and min cavity heating at the outside edges of the thrust curve as there is max reflected power back into the maggie.
Won't the sum of the thermal effects between the cavity and magnetron be more or less equal at all frequencies?
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#4076
by
Monomorphic
on 31 Jul, 2016 13:31
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How does this thrust bandwidth plot compare as against the S11 RL bandwidth plot?
Here is what the RL trace looks like superimposed over the data. This is the actual RL from VNA scaled to fit the frequencies shown.
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#4077
by
Monomorphic
on 31 Jul, 2016 13:47
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Any idea of the magnitude of the maximum force?
I have everything I need to determine this (scale, monofiliment, calibration weight kit). I hope to be able to answer your question soon, was going to work on this later today.
Total measurable displacement for the LDS is 20mm over a range of 0.66 - 5.7 Volts. The displacement shown on the graph is 0.19 Volts. That means the beam moved only 0.753mm!
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#4078
by
SeeShells
on 31 Jul, 2016 15:10
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Any idea of the magnitude of the maximum force?
I have everything I need to determine this (scale, monofiliment, calibration weight kit). I hope to be able to answer your question soon, was going to work on this later today.
Total measurable displacement for the LDS is 20mm over a range of 0.66 - 5.7 Volts. The displacement shown on the graph is 0.19 Volts. That means the beam moved only 0.753mm!
It was something, even though it was only the thickness of a piece of paper. It's a tribute to your engineering and build skills to resolve effectively this movement and nobody should forget you are moving a lot of mass around on your beam!
Well done!
My Best,
Shell
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#4079
by
Monomorphic
on 31 Jul, 2016 16:24
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Beam calibration complete. 100mg test. Total displacement for 100mg was 0.857 Volts. Which is 0.00857 Volts/mg.
Maximum total displacement of powered test was 0.186 Volts. 0.186/0.00857 = 21.7mg
21.7mg = 0.0002128 N = 0.2128 mN = 212.8 μN
