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In Quadcopters / Pagoda antenna:

Maarten Baert

Administrator

Comment #1: Mon, 11 Dec 2017, 1:48 (GMT+1, DST)

Quote


Quote: Lattonna

Sorry for being obtrusive - but we could wait, when you ll have time, becouze we really need it, and we gonna pay your time and work. Or if it is possible - we can buy re - tuning technology for antennas , if you wish

You would have to wait several years for me to complete my PhD first, because I'm not allowed to accept any side-jobs in the meantime. It's part of the contract.

In Quadcopters / Pagoda antenna:

Lattonna

Comment #2: Wed, 6 Dec 2017, 10:01 (GMT+1, DST)

Quote


Quote: Maarten Baert
Quote: Lattonna

hello, have question you about pagoda antennas - we bought one antenna, and now want to ask about some help - ask you to calculate configuration for this antenna with band frequency 2.4 - 2.5 Hhz, and how much it will cost ??

Several people have asked me to make a version for 2.45GHz, it's possible but it will be more than twice as large. Keeping the PCBs parallel to each other without extra support is going to be a problem. Cost is not much higher than the 5.8GHz Pagoda since most of the cost is the assembly, not the PCBs.

In any case, I don't have time to work on this right now. Re-tuning is harder than it looks, you can't just scale all the dimensions and expect it to work, because the PCB thickness and coax diameter stays the same.

Sorry for being obtrusive - but we could wait, when you ll have time, becouze we really need it, and we gonna pay your time and work. Or if it is possible - we can buy re - tuning technology for antennas , if you wish

In Quadcopters / Pagoda antenna:

Maarten Baert

Administrator

Comment #3: Wed, 6 Dec 2017, 1:13 (GMT+1, DST)

Quote


Quote: Lattonna

hello, have question you about pagoda antennas - we bought one antenna, and now want to ask about some help - ask you to calculate configuration for this antenna with band frequency 2.4 - 2.5 Hhz, and how much it will cost ??

Several people have asked me to make a version for 2.45GHz, it's possible but it will be more than twice as large. Keeping the PCBs parallel to each other without extra support is going to be a problem. Cost is not much higher than the 5.8GHz Pagoda since most of the cost is the assembly, not the PCBs.

In any case, I don't have time to work on this right now. Re-tuning is harder than it looks, you can't just scale all the dimensions and expect it to work, because the PCB thickness and coax diameter stays the same.

Last modified: Wed, 6 Dec 2017, 1:15 (GMT+1, DST)

In Quadcopters / Triple Feed Patch antenna:

Maarten Baert

Administrator

Comment #4: Wed, 6 Dec 2017, 1:10 (GMT+1, DST)

Quote


Quote: Race412

Hello Maarten,
We also have the triple feed patch antenna available on our store. Could you add our store to the table as well?

https://race412.com/product/triple-feed-patch/
$15
SMA and RPSMA

Thank You
Race 412

Can you specify which connectors you are using on the PCB as well as the coax? Is the PCB connector also RP-SMA or just one of the connectors on the coax?

In Quadcopters / Triple Feed Patch antenna:

Race412

Comment #5: Tue, 5 Dec 2017, 19:26 (GMT+1, DST)

Quote


Hello Maarten,
We also have the triple feed patch antenna available on our store. Could you add our store to the table as well?

https://race412.com/product/triple-feed-patch/
$15
SMA and RPSMA

Thank You
Race 412

In Quadcopters / Pagoda antenna:

Lattonna

Comment #6: Tue, 5 Dec 2017, 13:32 (GMT+1, DST)

Quote


hello, have question you about pagoda antennas - we bought one antenna, and now want to ask about some help - ask you to calculate configuration for this antenna with band frequency 2.4 - 2.5 Hhz, and how much it will cost ??

In Quadcopters / Triple Feed Patch antenna:

Actuna

Comment #7: Fri, 1 Dec 2017, 15:12 (GMT+1, DST)

Quote


Quote: Actuna

We produced a modified version of the Triple Feed Patch (hybrid) antenna - a diameter of 45mm. We are now finishing the tests of this antenna, the results are positive.

https://www.thingiverse.com/thing:2682348

In Quadcopters / Pagoda antenna:

Maarten Baert

Administrator

Comment #8: Wed, 29 Nov 2017, 4:00 (GMT+1, DST)

Quote


Quote: Kitchenman

trying to build a kit antenna. have question - RP-SMA male all my kits come with the pin. how do I get a socket pin? thanks

You order RP-SMA female ;).

In Quadcopters / Triple Feed Patch antenna:

Maarten Baert

Administrator

Comment #9: Wed, 29 Nov 2017, 3:34 (GMT+1, DST)

Quote


Quote: Andymidtf

Hi Maarten,

I am ordering from Seeed, there the PCB size can be much smaller - from the .dxf files I see part one is 24.9mm wide, and part 2 is 60.0mm wide - any reason not to use these sizes in the order page?
Also, neither Elecrow or Seeed provide the Panalizing option in the web form - any idea what will happen if this is not included in the order? I should get in contact with them for a personal quote?

Thanks very much!

Andy
:-)

PD do you have a paypal or accept bitcoin (better some other vcoin with todays tx rates!), even thou you offer these open source, I really think you deserve some renumeration for your excellent work!

If the manufacturer asks for the exact size, then you should do that. Elecrow doesn't do this though. If they don't offer panelization, then don't worry about it. Also, I don't accept donations, but thanks anyway :).

Quote: Prxbl

Since male SMA terminators are hard to find can I use a 49.9ohm resistor to terminate one of the sides permanently?

I plan to remove the SMA connector and just solder an SMD resistor between signal and ground in the place of the old connector.

You should just get the LHCP or RHCP variant instead of the hybrid if that is what you want. But yes, you can do this. It won't be perfect because the footprint is designed to cancel out some of the mismatch of the connector, but it will be pretty close.

Last modified: Wed, 29 Nov 2017, 3:37 (GMT+1, DST)

In Quadcopters / Triple Feed Patch antenna:

Prxbl

Comment #10: Mon, 27 Nov 2017, 13:06 (GMT+1, DST)

Quote


Since male SMA terminators are hard to find can I use a 49.9ohm resistor to terminate one of the sides permanently?

I plan to remove the SMA connector and just solder an SMD resistor between signal and ground in the place of the old connector.

In Quadcopters / Triple Feed Patch antenna:

Actuna

Comment #11: Sun, 26 Nov 2017, 22:03 (GMT+1, DST)

Quote


Hello ...

I would like to inform you about the production and sale of the Triple Feed Patch (hybrid):

Manufacturer: ACTUNA

URL: https://actuna.com/Antenna-Triple-Feed-Patch-1-5-8GHz-RHCP-LHCP-p13210

Price: 9,85 $

- hybrid
- SMA (female)
- SMA and RP-SMA - Includes semi-rigid coax (SMA male – SMA male or SMA male - RP-SMA female).

Notes: Each antenna is measured individually and gets its own parameters tab. SMA and RP-SMA - Includes semi-rigid coax (SMA male – SMA male or SMA male - RP-SMA female). Fast delivery in the EU (3-10 days).

Contacts: actuna@actuna.pl

PS:

We produced a modified version of the Triple Feed Patch (hybrid) antenna - a diameter of 45mm. We are now finishing the tests of this antenna, the results are positive.

Last modified: Sun, 26 Nov 2017, 22:05 (GMT+1, DST)

In Quadcopters / Pagoda antenna:

Actuna

Comment #12: Sun, 26 Nov 2017, 21:56 (GMT+1, DST)

Quote


Hello ...

I would like to inform you about the production and sale of the pagoda antenna 2B:

Manufacturer: ACTUNA

URL: https://www.actuna.com/category/?q=pagoda

Price: 6,90 $

- RHCP
- LHCP
- SMA
- RP-SMA

Notes: Each antenna is measured individually and gets its own parameters tab. Straight or 90-degree connector available. Three different lengths available. Fast delivery in the EU (3-10 days).

Contacts: actuna@actuna.pl

Last modified: Sun, 26 Nov 2017, 21:56 (GMT+1, DST)

In Quadcopters / Pagoda antenna:

Kitchenman

Comment #13: Sat, 25 Nov 2017, 20:16 (GMT+1, DST)

Quote


trying to build a kit antenna. have question - RP-SMA male all my kits come with the pin. how do I get a socket pin? thanks

In Quadcopters / Triple Feed Patch antenna:

Andymidtf

Comment #14: Thu, 16 Nov 2017, 20:41 (GMT+1, DST)

Quote


Quote: Maarten Baert

The correct settings are:

- PCB Size: "5cm Max * 5cm Max" (part1) / "10cm Max * 10cm Max" (part2)
...
- Panelizing: "Single PCB with milling"

Hi Maarten,

I am ordering from Seeed, there the PCB size can be much smaller - from the .dxf files I see part one is 24.9mm wide, and part 2 is 60.0mm wide - any reason not to use these sizes in the order page?
Also, neither Elecrow or Seeed provide the Panalizing option in the web form - any idea what will happen if this is not included in the order? I should get in contact with them for a personal quote?

Thanks very much!

Andy
:-)

PD do you have a paypal or accept bitcoin (better some other vcoin with todays tx rates!), even thou you offer these open source, I really think you deserve some renumeration for your excellent work!

In Model Creator / Documentation:

Dragonite

Comment #15: Fri, 10 Nov 2017, 14:52 (GMT+1, DST)

Quote


I'm using it for stuff like this: https://www.youtube.com/watch?v=8ajRno-6grE

but I'm curious as to what other people are doing too, as far as I know I'm one of the only people who've stuck with 3D in GMS for this long :P

Last modified: Fri, 10 Nov 2017, 14:52 (GMT+1, DST)

In Quadcopters / Pagoda antenna:

Dontpeek

Comment #16: Mon, 6 Nov 2017, 14:16 (GMT+1, DST)

Quote


Quote: Maarten Baert

There are some problems with the use of thinner coax. It requires significant re-tuning, I haven't really looked into it seriously.

I think it would be amazing if you could get that working. Everything is trending towards small and light it seems and going from sma to a ufl antenna is a huge weight savings. For smaller quads like the 2" class you can't even use a full size sma antenna because of the weight. Right now the only real option is the luminier axii which is a ufl antenna that only weighs a couple grams.

In Quadcopters / Triple Feed Patch antenna:

Maarten Baert

Administrator

Comment #17: Sat, 4 Nov 2017, 3:43 (GMT+1, DST)

Quote


Quote: Ryan

What is center frequency? I run my vtx on channel 5658. Am I off center? Is center as close to 5800 as possible? Does it matter how the patch sits on the goggles ? Is there a up or down/top or bottom of the patch?

The center frequency is 5.8 GHz. As you can see in the specs, the bandwidth is 660 MHz (5.47 – 6.13 GHz), so 5.658 GHz will work fine.

There is no top/bottom, just point the patch in the direction of the transmitter and you are fine.

Quote: Vlado

Would it work well if I solder RG402 cable directly to the PCB? How about soldering rx5808 video rx module on the antenna? :D

That won't work well with the current PCB layout. The matching will be bad. The layout you see now is specifically tuned to match well to those vertical SMA connectors.

In Quadcopters / Pagoda antenna:

Maarten Baert

Administrator

Comment #18: Sat, 4 Nov 2017, 3:27 (GMT+1, DST)

Quote


Quote: Joze

Hi Maarten,

first congratulations for your design and thanks for sharing your work.

Do we have to pay attention to the material from which the Heat Shrink is made of?

I have just ordered PCB’s for your new Pagoda 3B based on Fishpepper’s panel design. I would prefer Heat Shrink for antenna protection, but I’m not confident I wouldn’t detune or block the signal to much.

Regards, Joze

PS I don’t know how to explain the experience I had with the ESP8266 WiFi Module. If I encased it into a Heat Shrink, the signal completely disappeared. It was working with full signal if I removed Heat Shrink from the antenna part of the PCB.

Since heat shrink manufacturers don't provide specs for this, there is no way to accurately predict the impact. Just try it. Usually the center frequency is reduced by about 200 MHz, and the 2B/3B variants are specifically designed to counteract this.

Assuming that you are referring to the ESP8266 module from Sparkfun, based on the photo I would guess that it's using a very narrowband antenna. It looks like some kind of folded monopole which is too short for its target frequency, so it behaves capacitively. They tune it out with a shorted stub, which is essentially a small inductor. The result is a narrowband LC oscillator that also behaves a bit like an antenna. This type of antenna is very sensitive to anything that would change the capacitance, such as nearby plastic objects (heat shrink).

The Pagoda antenna has a much higher bandwidth, so it isn't affected as easily by heat shrink. Also, even when you cover the Pagoda with heat shrink, most of the electromagnetic field is still located in air. As long as you don't fill the entire antenna with hot glue or silicone, the impact is pretty minor.

Last modified: Sat, 4 Nov 2017, 3:27 (GMT+1, DST)

In Quadcopters / Triple Feed Patch antenna:

Vlado

Comment #19: Thu, 2 Nov 2017, 20:25 (GMT+1, DST)

Quote


Would it work well if I solder RG402 cable directly to the PCB? How about soldering rx5808 video rx module on the antenna? :D

In Quadcopters / Triple Feed Patch antenna:

Ryan

Comment #20: Tue, 31 Oct 2017, 14:29 (GMT+1, DST)

Quote


What is center frequency? I run my vtx on channel 5658. Am I off center? Is center as close to 5800 as possible? Does it matter how the patch sits on the goggles ? Is there a up or down/top or bottom of the patch?

Last modified: Wed, 1 Nov 2017, 23:12 (GMT+1, DST)

In Quadcopters / Pagoda antenna:

Joze

Comment #21: Sun, 29 Oct 2017, 22:53 (GMT+1, DST)

Quote


Hi Maarten,

first congratulations for your design and thanks for sharing your work.

Do we have to pay attention to the material from which the Heat Shrink is made of?

I have just ordered PCB’s for your new Pagoda 3B based on Fishpepper’s panel design. I would prefer Heat Shrink for antenna protection, but I’m not confident I wouldn’t detune or block the signal to much.

Regards, Joze

PS I don’t know how to explain the experience I had with the ESP8266 WiFi Module. If I encased it into a Heat Shrink, the signal completely disappeared. It was working with full signal if I removed Heat Shrink from the antenna part of the PCB.

In SimpleScreenRecorder / Improving performance:

Maarten Baert

Administrator

Comment #22: Sun, 29 Oct 2017, 2:44 (GMT+1, DST)

Quote


Quote: Glassmenagerie

Hi Maarten, I want to create a DVD from a file made with Simple Screen Recorder. Which DVD burning software would you suggest and what would the Simple Screen Recorder codec settings need to be I want to play the DVD on a Windows PC. This Windows PC will probably not have VLC or any after market software installed.

Thanks ! I've been using your software for several years now and am very glad to have it installed on my Ubuntu system.

Best Regards,
RDL

DVD codecs are standardized. It doesn't matter what you use in SSR, you will have to transcode it to DVD format anyway (SSR can't do this directly). So just use a high quality format so you don't lose too much detail in the conversion (for example, H.264 with crf 20).

In Quadcopters / Realacc Pagoda-2:

Maarten Baert

Administrator

Comment #23: Sun, 29 Oct 2017, 2:42 (GMT+1, DST)

Quote


Quote: Nepoxx

Where do you put the heat shrink though? The banggood pagodas are shipped with a protective rubber on the 3 rings, that might be enough to shift the frequency down a bit?

That could work, but I would try putting heat shrink around the entire thing to make it more robust.

In SimpleScreenRecorder / Troubleshooting:

Maarten Baert

Administrator

Comment #24: Sun, 29 Oct 2017, 2:41 (GMT+1, DST)

Quote


Quote: Vafa

I have the application but I can't use it due to windows size. Take a look at print screen:
https://drive.google.com/file/d/0B-BnCnSM7woDdTNVR1dhdkVWb3M/view?usp=sharing

I can't change the windows size, my screen resolution is on maximum, I try different size but same issue.
This is my configurations:
Fedora 26 64bit
Graphics: Intel® Ivybridge Mobile
GNOME : Version 3.24.2
simplescreenrecorder-0.3.8-4.fc26.x86_64

Quote: Robertdaleweir

Vafa
I have the same problem on F24 and I found out what it is. I have a banner at the top and bottom of my Screen. If I go to 'tweak-tool' and turn off the bottom taskbar (banner) I see the Continue etc and can run the program. If I do not do this I cannot even get it started. Maybe if some empty lines followed the Continue line so the banner would not cover the Actionable Buttons, it would solve this problem. I guess it is a Gnome issue but I think it could be overcome by adding a few 'Blank Lines' to the Applications Windows. I want desperately to use this app, as I have seen great comments on Youtube from users, but I do not want to turn these banners off every time. i see on your Screen Shot and you do not have a bottom Banner but I think if you, temporarily, turn off your top one you will be able to see the Continue line. YMMV.

The problem is that your screen resolution just doesn't leave enough room for the program. This will be fixed in the next version (it automatically adds scroll bars when it detects this problem). You can already get the new version from GitHub if you compile it yourself.

In SimpleScreenRecorder / Translations:

Maarten Baert

Administrator

Comment #25: Sun, 29 Oct 2017, 2:38 (GMT+1, DST)

Quote


Quote: Nullgeppetto

Hello Maarten, and congratulations for the great software! I installed it via the AUR (ArchLinux) and it automatically uses the Greek language, which I'd like to change. Is there any config file I could edit, or any other ways of changing the language to English? many thanks for your time.

The language is based on the LC_MESSAGES environment variable. You can change this either in your system settings, or you can override it for SSR specifically by creating a launcher that runs SSR as follows:

LC_MESSAGES=en_US.UTF-8 simplescreenrecorder

In Quadcopters / Antennas:

Maarten Baert

Administrator

Comment #26: Sun, 29 Oct 2017, 2:36 (GMT+1, DST)

Quote


Quote: Saboo

We use 915MHz for telemetry. Does your simulation software work for the 915MHz range?

Would like to have a design for 915MHz.

Have you worked on other frequency ranges such as 1.2-1.3GHz?

Thanks

A Pagoda antenna for 915 MHz would be way too big and heavy. Just use a cloverleaf instead, at those low frequencies the issues with cloverleafs aren't that bad.

Quote: Ddale

Hi Marten,
I saw that you can eliminate one of the pcb's and have the performance of a regular coverleaf my question is which pcb? is it the small one?

Thanks
David

Yes, the smallest PCB can be removed, but doing so makes the axial ratio significantly worse.

Quote: Fernandez

Possibly we could still gain some extra range, if we implement directly on the PCB of the antenna a decent low noise amplifier stage and maybe small 5.8ghz BPF behind.

I assume based on the low price of our RX modules, the input stages probably not very decent lna....The first stages of RX is most important.

Will make the antenna more expensive and need little bit of power, but like to try it...

In theory yes, but the Pagoda antenna doesn't really have any room where you could place this amplifier. However the Triple Feed Patch antenna has plenty of space, and I have actually considered creating a version that includes a built-in LNA (specifically the SKY65404, which has a noise figure of about 1.2 dB).

In Model Creator / Documentation:

Maarten Baert

Administrator

Comment #27: Sun, 29 Oct 2017, 2:28 (GMT+1, DST)

Quote


The compatibility issues are mostly caused by Game Maker 7. Unfortunately Model Creator relies on the Max WinAPI DLL which doesn't work properly with newer versions of Game Maker, so I can't upgrade it.

In most cases you can fix the compatibility problems by running Model Creator in compatibility mode, and possibly even in administrator mode, but if that doesn't work, I can't really do anything to fix it other than rewriting the entire program in a more modern programming language. Since this is an old tool that isn't used by a huge number of people, I don't really feel like doing that.

I'm actually really surprised that there are any users left at all, I had gotten the impression that very few people were still using Game Maker for 3D games now that engines such as Unity have become so accessible to hobbyists. But somehow Model Creator is still downloaded 200-300 times each month. What are you using it for?

In Quadcopters / Pagoda antenna:

Maarten Baert

Administrator

Comment #28: Sun, 29 Oct 2017, 2:14 (GMT+1, DST)

Quote


Quote: Dontpeek

Any updates on the UFL version? Would be really nice for micros.

There are some problems with the use of thinner coax. It requires significant re-tuning, I haven't really looked into it seriously.

Quote: Austinthemighty

where are the python scripts for the antennas?

Here.

Quote: Gsimpson

Hello Maarten, I have worked on an idea to make this antenna nearly indestructible. I believe it would need a bit of retuning to get the signal quality back to the original design, but right now my idea seems to be working phenominally! Is there a way I could get in touch with you to show you my idea?

I see you already found my email address :).

Quote: Virginia Jim

Maarten:
I was wondering if it would make sense (or even be equivalent) to mount your pagoda antenna on the aircraft upside down? This would allow us to position these antennas either between the legs of the landing gear, or close to the fuselage under the wing, protecting the antenna somewhat from tree limbs, etc.
The RF distribution pattern appears to be a near pure doughnut shape, presumably distributed equally above and below the antenna's elevation. Wouldn't it work equally well if mounted upside down?
Also, I prefer short stalk antennas. Is there an argument against them?
Thanks for your comments.
VJ

It will work even better upside-down, because you won't be affected by the 'shadow' region created by the body of the RC model. Just remember that you won't get a signal when you are flying right above yourself.

The only problem with short antennas is that the 'shadow' region becomes much bigger. But if the antenna is already pointing down, this is not an issue.

In Quadcopters / Triple Feed Patch antenna:

Maarten Baert

Administrator

Comment #29: Sun, 29 Oct 2017, 2:05 (GMT+1, DST)

Quote


Quote: Erwin024

Hi, when using triple feed patch antenna, do I still have to use diversity module?
Or if I'll use diversity module, which can I pair with triple feed patch antenna?
Thanks

Typically directional antennas like these are combined with an omnidirectional antenna (like the Pagoda) in a diversity setup. You can use them without diversity if you want, but then you need to make sure that you are always pointing the antenna in the right direction.

Any diversity module should work with any antenna, as long as the connectors are compatible.

Quote: Feket663

Hi! I'd like buy this great designed antenna. But have a question: can I use a cheap 50 ohm SMA dummy load from ebay or aliexpress. My biggest problem is this dummy loads specified only 3 GHz.

For example: link

Can I use it?

Any 50 ohm terminator should work, it's not critical. You can even use the antenna without a terminator, it will still work fine, the axial ratio will just be slightly worse because the opposite polarization will be reflected instead of absorbed.

Quote: Flick1

Hi Maarten,
When you mention using the surface mount SMC connectors for performance reasons, what kind of performance degradation would you expect if you used the PCB mount connectors with longer legs?

The problem is that the through-hole connectors would need a hole in the ground plane, which interferes with the patch antenna on the other side. It's also really difficult to get a good 50 ohm match with those connectors at high frequencies.

Quote: Gs550t1981

I'm not to good at understanding the graphs. What is the radiation pattern? When pointing the antenna straight ahead is it basically 55° verticle and horizontal? What makes them better than say a crosshair? I am asking not to bust your chops. I love the Pagodas and are the only antenna I use. I picked this up and want to know what it would be ideal to use for... Thanks
Jeff

If you point the patch straight at the other antenna, that's considered 0 degrees (the top of the radiation pattern graph).

These aren't necessarily better than crosshairs, but they are easier to manufacture because they aren't as sensitive to deviations in length of the radiating elements. Also, this antenna achieves a good axial ratio across the entire bandwidth, whereas crosshairs typically only get a good axial ratio close to their center frequency. Finally, this antenna has a good axial ratio in all directions, not just when it is pointed straight at the other antenna but also at an angle. This is rarely the case for rectangular patches or crosshair antennas.

Quote: Fpvbrain

It will definitely shift the center frequency LOL since when determined PLA or ABS the center frequency Maarten Baert I would like gladly times a field strength test of ABS or PLA from you see which you can send me gladly to info@FPV-BRAIN.net then you may not synonymous PCB More paint. :-)

Quote: Fpvbrain

Conductivity of insulators κ in S / cm rubber10-16 polystyrene 10-18 porcelain 10-15

... what?

Conductivity is irrelevant in this context, what matters is dielectric constant and loss tangent. The dielectric constant of air is 1.0, for plastic it is usually somewhere between 2.0 and 3.0 depending on the type and density. The resonance frequency of a patch is inversely proportional to the square root of the dielectric constant. This is basic antenna theory which you can find in any book that discusses patch antennas.

For example, if you used a polyethylene spacer (dielectric constant 2.26), you will shift the resonant frequency from 5.8 GHz down to 3.86 GHz. Of course the feed network isn't affected by this since it is on the other side of the PCB. So you now have an antenna with a 5.8 GHz feed network and a 3.86 GHz patch, so your antenna will be pretty much useless.

The Pagoda was less susceptible to this because the space between the plates contains only a small part of the electromagnetic fields. As a result you could put a spacer between the two and still get an antenna that was usable. This is not the case for patch antennas, where 99% of the electromagnetic field is concentrated between the two plates.

Quote: Akinys

If to use only RHCP, what option will be best:
- do not solder SMA connector on LHCP side;
- solder SMA connector on LHCP side and leave open;
- solder SMA connector on LHCP side and put 50ohm load;
- remove from pcb feeder line from LHCP side ?

Option 3, but if you don't want to add the SMA connector, you could also solder a 50 ohm SMD resistor directly to the PCB. Removing the connector is also possible, but don't remove the feed line. The feed network in the center has been designed with the feed line taken into account, removing it will affect the performance.

An even better option is to use an alternative feeding network that is LHCP or RHCP only, but I haven't made that one public yet because I didn't have time.

In Quadcopters / Pagoda antenna:

Virginia Jim

Comment #30: Sat, 28 Oct 2017, 16:41 (GMT+1, DST)

Quote


Maarten:
I was wondering if it would make sense (or even be equivalent) to mount your pagoda antenna on the aircraft upside down? This would allow us to position these antennas either between the legs of the landing gear, or close to the fuselage under the wing, protecting the antenna somewhat from tree limbs, etc.
The RF distribution pattern appears to be a near pure doughnut shape, presumably distributed equally above and below the antenna's elevation. Wouldn't it work equally well if mounted upside down?
Also, I prefer short stalk antennas. Is there an argument against them?
Thanks for your comments.
VJ

Last modified: Sat, 28 Oct 2017, 16:45 (GMT+1, DST)