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In Quadcopters / Pagoda antenna:

Maarten Baert

Administrator

Comment #1: Sun, 3 Feb 2019, 21:45 (GMT+1, DST)

Quote


Quote: Omrsramsay

Would a pagoda antenna work for 433, 900, 1.2, 2.4 frequencies? I have a 1.2G skewed planar antenna that seems to work.

Please read the earlier comments - it is possible but not very practical, the antenna would be way too big.

In Quadcopters / Pagoda antenna:

Omrsramsay

Comment #2: Fri, 1 Feb 2019, 21:47 (GMT+1, DST)

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Would a pagoda antenna work for 433, 900, 1.2, 2.4 frequencies? I have a 1.2G skewed planar antenna that seems to work.

In Quadcopters / Triple Feed Patch antenna:

Maarten Baert

Administrator

Comment #3: Sat, 19 Jan 2019, 4:18 (GMT+1, DST)

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Quote: Yoppy

Thank you Maarten for your reply.

Another related question, if I decrease the patch spacing in order to get higher center frequency, but how does it affect other performance parameters, such as axial ratio, radiation pattern, etc? Will they be compromized?

I don't think they will change significantly. The axial ratio is determined mostly by the feed network. Of course if you try to use the feed network at a frequency significantly different from what it was designed for, then it may not work as well.

Last modified: Sat, 19 Jan 2019, 4:19 (GMT+1, DST)

In Quadcopters / Triple Feed Patch antenna:

Yoppy

Comment #4: Sun, 13 Jan 2019, 17:02 (GMT+1, DST)

Quote


Thank you Maarten for your reply.

Another related question, if I decrease the patch spacing in order to get higher center frequency, but how does it affect other performance parameters, such as axial ratio, radiation pattern, etc? Will they be compromized?

In SimpleScreenRecorder / Troubleshooting:

Maarten Baert

Administrator

Comment #5: Fri, 11 Jan 2019, 1:25 (GMT+1, DST)

Quote


Quote: Kode54

Hi, I thought I’d register to point out that the desktop flickering issue also occurs with Iris Pro graphics and KWin, so it isn’t specific to Mutter.

Good to know. It seems that there are actually two separate issues with similar symptoms, one related to the Intel video driver and the other related to Mutter.

In SimpleScreenRecorder / Recording Steam games:

Maarten Baert

Administrator

Comment #6: Fri, 11 Jan 2019, 0:55 (GMT+1, DST)

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Quote: Djcj
Quote

[...] because Steam games are 32-bit (as far as I know).

Not true. Most games are, but some are 64 bit or offer binaries for both architectures.

All right, I will update it.

In Quadcopters / Triple Feed Patch antenna:

Maarten Baert

Administrator

Comment #7: Thu, 10 Jan 2019, 22:33 (GMT+1, DST)

Quote


Quote: Esfateev

Hi!
Is it possible to "scale" antenna to work with 2.4? Do you trying another frequences for antennas? (like 1.3 or 2.4)

Thank you for your hard work! You've made awesome antennas!
BR, Eugene

Yes, this is possible, but you will have to re-simulate the feed network, which is quite tricky. Just scaling it by a fixed factor won't be very accurate, especially for the hybrid variant.

Quote: Yoppy

Hi Maarten,

I have made several pieces of RHCP version of triple feed patch antenna.
I have made sure the PCB spec is correct as you have stated in the instruction.
I order the PCBs from Seeedstudio.
Also, I solder the antennas with the Farvew's jigs.

However, all of the antenna I make, center frequency is consistently at around 5.2-5.3 GHz. At 5.8 GHz, the S11 is around 19-14 dB.

What would you suggest? Decrease the patch spacing?
Thanks for suggestions.

Yes, decreasing the space between the PCBs will increase the center frequency. Your jig may be inaccurate, maybe the spacing is already too high. Try measuring it with calipers. If that doesn't explain it, perhaps the manufacturer has switched to a different brand of FR4.

Last modified: Thu, 10 Jan 2019, 22:36 (GMT+1, DST)

In Quadcopters / Pagoda antenna:

Maarten Baert

Administrator

Comment #8: Thu, 10 Jan 2019, 22:32 (GMT+1, DST)

Quote


Quote: Zandrey

Hi, Martin. I am somehow designing antennas. You got a very cool antenna. I would like to remake it at a frequency of 980 MHz. I took most of the sizes of the files that you placed, but there is some kind of accuracy and the directional pattern is not the same. Did you do modeling in ANSYS? What items you used in the construction?

Check my earlier comments, it's technically possible but very impractical. The antenna is just too large.

Yes, I use ANSYS HFSS for simulation. The model is made with boolean operations where possible, and the curved tracks are made with paths (multiple arcs).

In Quadcopters / Triple Feed Patch antenna:

Yoppy

Comment #9: Fri, 4 Jan 2019, 0:58 (GMT+1, DST)

Quote


Hi Maarten,

I have made several pieces of RHCP version of triple feed patch antenna.
I have made sure the PCB spec is correct as you have stated in the instruction.
I order the PCBs from Seeedstudio.
Also, I solder the antennas with the Farvew's jigs.

However, all of the antenna I make, center frequency is consistently at around 5.2-5.3 GHz. At 5.8 GHz, the S11 is around 19-14 dB.

What would you suggest? Decrease the patch spacing?
Thanks for suggestions.

In SimpleScreenRecorder / Recording Steam games:

Djcj

Comment #10: Sat, 29 Dec 2018, 4:32 (GMT+1, DST)

Quote


Quote

[...] because Steam games are 32-bit (as far as I know).

Not true. Most games are, but some are 64 bit or offer binaries for both architectures.

In Quadcopters / Triple Feed Patch antenna:

Esfateev

Comment #11: Tue, 25 Dec 2018, 13:01 (GMT+1, DST)

Quote


Hi!
Is it possible to "scale" antenna to work with 2.4? Do you trying another frequences for antennas? (like 1.3 or 2.4)

Thank you for your hard work! You've made awesome antennas!
BR, Eugene

In SimpleScreenRecorder / Troubleshooting:

Kode54

Comment #12: Tue, 25 Dec 2018, 7:54 (GMT+1, DST)

Quote


Hi, I thought I’d register to point out that the desktop flickering issue also occurs with Iris Pro graphics and KWin, so it isn’t specific to Mutter.

In Quadcopters / Pagoda antenna:

Zandrey

Comment #13: Thu, 20 Dec 2018, 5:41 (GMT+1, DST)

Quote


Hi, Martin. I am somehow designing antennas. You got a very cool antenna. I would like to remake it at a frequency of 980 MHz. I took most of the sizes of the files that you placed, but there is some kind of accuracy and the directional pattern is not the same. Did you do modeling in ANSYS? What items you used in the construction?

In SimpleScreenRecorder / Translations:

Cges30901

Comment #14: Mon, 26 Nov 2018, 15:38 (GMT+1, DST)

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Hi Maarten,

I want to update Traditional Chinese (zh_TW) translation of ssr.

In Quadcopters / Triple Feed Patch antenna:

Dave

Comment #15: Sun, 25 Nov 2018, 3:07 (GMT+1, DST)

Quote


Interesting and quite simple design!

Last modified: Mon, 26 Nov 2018, 21:30 (GMT+1, DST)

In Quadcopters / Pagoda antenna:

Maarten Baert

Administrator

Comment #16: Wed, 7 Nov 2018, 12:50 (GMT+1, DST)

Quote


Quote: Wolfdale

Hi Maarten, thanks for this awesome antenna design. Do you think that covering the coax bewteen the PCB's with heatshrink, will affect the resonant frequency too much?

Probably a little bit, but not significantly. However, how are you planning to do the soldering when the heat shrink is already there? It will probably melt. I also don't really see the point of it.

In Quadcopters / Pagoda antenna:

Wolfdale

Comment #17: Tue, 6 Nov 2018, 0:20 (GMT+1, DST)

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Hi Maarten, thanks for this awesome antenna design. Do you think that covering the coax bewteen the PCB's with heatshrink, will affect the resonant frequency too much?

In Quadcopters / Triple Feed Patch antenna:

Maarten Baert

Administrator

Comment #18: Tue, 30 Oct 2018, 1:28 (GMT+1, DST)

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Quote: Sebbaling

First of all, thank you for your great work Maarten!

I have two questions:

1) would it be problematic if i connect the antenna directly to a 45° angle adapter on my receiver without the coax cable?

2) is the antenna supposed to be oriented in a specific manner (like one site has to be towards the sky and the other to the ground) or does it only has to be pointed toward the transmitting antenna no matter the rest of the orientation?

regards
Sebba

1) This is fine. Just keep enough distance between the receiver and the tracks on the PCB. Ideally 1cm or more.

2) It doesn't matter as long as you point it at the transmitter.

Last modified: Tue, 30 Oct 2018, 1:29 (GMT+1, DST)

In Quadcopters / Triple Feed Patch antenna:

Sebbaling

Comment #19: Mon, 29 Oct 2018, 15:51 (GMT+1, DST)

Quote


First of all, thank you for your great work Maarten!

I have two questions:

1) would it be problematic if i connect the antenna directly to a 45° angle adapter on my receiver without the coax cable?

2) is the antenna supposed to be oriented in a specific manner (like one site has to be towards the sky and the other to the ground) or does it only has to be pointed toward the transmitting antenna no matter the rest of the orientation?

regards
Sebba

In Quadcopters / Pagoda antenna:

Maarten Baert

Administrator

Comment #20: Wed, 17 Oct 2018, 22:55 (GMT+1, DST)

Quote


Quote: George

I heard the pagoda is copy of this patent:
https://patents.google.com/patent/KR101315546B1/en
Is that true?

It is certainly not a copy, I was not aware of that patent until it was pointed out to me a few days ago. Compare the images and you will see that there are quite some differences.

To me it seems like this patent would not cover the Pagoda because it explicitly claims a design consisting of one PCB with tracks on both sides, whereas the Pagoda is made out of multiple PCBs with only one set of tracks on each PCB. But I'm not a lawyer, please don't take my word for it. The patent system varies between countries and what is and isn't covered can be very confusing.

In Quadcopters / Pagoda antenna:

George

Comment #21: Thu, 11 Oct 2018, 16:50 (GMT+1, DST)

Quote


I heard the pagoda is copy of this patent:
https://patents.google.com/patent/KR101315546B1/en
Is that true?

In Quadcopters / Pagoda antenna:

Maarten Baert

Administrator

Comment #22: Sat, 15 Sep 2018, 17:51 (GMT+1, DST)

Quote


Quote: Dabit

A little bit of feedback: using RG316 and a small piece of 'çopper tube' taken from the RG401 seems to work absolutely fine. I am running out of RC control range before the video becomes unuseable.
The RG316 itself is quite a bit weaker than RG401. The first try ended up with an empty SMA connector still attached to the quad and an antenna nowhere to be found.

The second one uses more plastic. The RG316 is wrapped in 4mm OD pneumatic polyurethane tubing, and that contraption is wrapped in 6mm OD PA12 pneumatic tubing. This limits the bending radius of the RG316, prevents buckling of the polyamid tubing and it is quite rigid but can flex more than 90 degrees. I also moved the SMA inside the quad and attached the tubing to the quad; the SMA is a weak spot.

https://www.icecoldcomputing.com/directlink/drone/quad_antenna_RG316.jpg

So far this has survived a gazillion crashes and cartwheels in trees, on gravel, on concrete, in sand and in tall grass. Frame arms start delaminating, antenna holds up fine.

To improve on this further I think I will turn a thin walled enclosure for the PCB's from high density polyethylene with a 'socket' that fits the 6mm polyamid tubing. Polyethylene exhibits a slightly lower loss tangent and dielectric constant than ABS, and it is far more abrasion resistant.

Nice work :).

In Quadcopters / Pagoda antenna:

Dabit

Comment #23: Fri, 14 Sep 2018, 11:44 (GMT+1, DST)

Quote


A little bit of feedback: using RG316 and a small piece of 'çopper tube' taken from the RG401 seems to work absolutely fine. I am running out of RC control range before the video becomes unuseable.
The RG316 itself is quite a bit weaker than RG401. The first try ended up with an empty SMA connector still attached to the quad and an antenna nowhere to be found.

The second one uses more plastic. The RG316 is wrapped in 4mm OD pneumatic polyurethane tubing, and that contraption is wrapped in 6mm OD PA12 pneumatic tubing. This limits the bending radius of the RG316, prevents buckling of the polyamid tubing and it is quite rigid but can flex more than 90 degrees. I also moved the SMA inside the quad and attached the tubing to the quad; the SMA is a weak spot.

https://www.icecoldcomputing.com/directlink/drone/quad_antenna_RG316.jpg

So far this has survived a gazillion crashes and cartwheels in trees, on gravel, on concrete, in sand and in tall grass. Frame arms start delaminating, antenna holds up fine.

To improve on this further I think I will turn a thin walled enclosure for the PCB's from high density polyethylene with a 'socket' that fits the 6mm polyamid tubing. Polyethylene exhibits a slightly lower loss tangent and dielectric constant than ABS, and it is far more abrasion resistant.

Last modified: Fri, 14 Sep 2018, 11:45 (GMT+1, DST)

In Quadcopters / Pagoda antenna:

Maarten Baert

Administrator

Comment #24: Mon, 27 Aug 2018, 0:20 (GMT+1, DST)

Quote


Quote: Dabit

Hi Maarten,

Thanks a lot for designing these easy to build and very performant antennas, and especially for making these open to the public!

I had the Fishpepper 4x4 panels made, all in all this was the cheapest option for only $4.99/10 panels. If anyone need a few PCB's, contact me.
So I am not worried about crushing an antenna once in a while. However, the thing I break the most is the RG402 cable. I have some of the 'expensive' stuff with a solid copper shield instead of the soldered braid that most Chinese manufacturers seem to use.

But the general flow is still 'build antenna, fly antenna, crash, bend cable straight, crash, bend cable straight, oops, shell ruptures'. It takes a little longer with the copper-shield RG402 compared to the soldered-braid, but it is still the main failure.

I would love to use a more flexible coax towards the antenna and use some nylon tubing or TPU to align the antenna to the quad. Just like people do with those AXII antennas. But somewhere you said that using RG316 was not recommended since the coax shield between the three PCB's is an active part of the antenna structure.

But what if I assemble the antenna using the copper shield of the RG402 and solder an RG316 cable inside, essentially filling the gap between the RG316 shield and the copper tube with solder? Would that work?

Yes, that would work. Only the outer diameter of the coax is important. If you can find another type of flexible coax with similar diameter, that is fine too. The problem with RG316 is just that it is too thin.

In Quadcopters / Pagoda antenna:

Dabit

Comment #25: Fri, 24 Aug 2018, 13:28 (GMT+1, DST)

Quote


Hi Maarten,

Thanks a lot for designing these easy to build and very performant antennas, and especially for making these open to the public!

I had the Fishpepper 4x4 panels made, all in all this was the cheapest option for only $4.99/10 panels. If anyone need a few PCB's, contact me.
So I am not worried about crushing an antenna once in a while. However, the thing I break the most is the RG402 cable. I have some of the 'expensive' stuff with a solid copper shield instead of the soldered braid that most Chinese manufacturers seem to use.

But the general flow is still 'build antenna, fly antenna, crash, bend cable straight, crash, bend cable straight, oops, shell ruptures'. It takes a little longer with the copper-shield RG402 compared to the soldered-braid, but it is still the main failure.

I would love to use a more flexible coax towards the antenna and use some nylon tubing or TPU to align the antenna to the quad. Just like people do with those AXII antennas. But somewhere you said that using RG316 was not recommended since the coax shield between the three PCB's is an active part of the antenna structure.

But what if I assemble the antenna using the copper shield of the RG402 and solder an RG316 cable inside, essentially filling the gap between the RG316 shield and the copper tube with solder? Would that work?

In Model Creator / Documentation:

Maarten Baert

Administrator

Comment #26: Fri, 3 Aug 2018, 22:10 (GMT+1, DST)

Quote


Quote: Bluepixel

Hey there, pls read the full comment before clicking away, im begging you that you can maybe make an gml to 3d model or make it so that you can export to 3d models in model creato because i really want to have my 3d model in blender or any other 3d engine :/ thanks, -Blue

You can already do this with Game Maker. Just run the GML code and have Game Maker save the model with d3d_model_save. You can then open it with Model Creator.

In Model Creator / Documentation:

Bluepixel

Comment #27: Tue, 31 Jul 2018, 18:08 (GMT+1, DST)

Quote


Hey there, pls read the full comment before clicking away, im begging you that you can maybe make an gml to 3d model or make it so that you can export to 3d models in model creato because i really want to have my 3d model in blender or any other 3d engine :/ thanks, -Blue

In Quadcopters / Polarization:

Maarten Baert

Administrator

Comment #28: Thu, 26 Jul 2018, 19:00 (GMT+1, DST)

Quote


Quote: Dcara55135

Here is an interesting observation I do not understand. I have 2 RHCP patch antennas.

1) I point the 2 antennas at each other (stright in line boresights) with one as Tx and one as Rx (1600 MHz). I observe only freespace path loss of the correct value for the distance (5 ft). I actually expected some rejection due to crosspol (maybe 20 dB?) thinking if it received RHCP it would transmit LHCP.

2) Believing now that the observation implied a Rx RHCP antenna would also Tx RHCP I moved the Tx antenna next to the Rx antenna (2ft away) facing the same direction as the Rx antenna (parallel boresights) so now the transmitted wave would be rotating opposite of the previous test and I would see the cross pol and beam width rejection. Alas it was not the case. In short, with the Tx antenna in this position facing the same direction as the Rx was facing showed 10dB more signal at the Rx antenna than when I turned the Tx antenna 180 degrees facing the opposite direction.

Do you have an idea of what is happening?

A RHCP antenna will always either produce or receive RHCP waves, regardless of whether you use it as a transmitter or a receiver. It's a bit counter-intuitive, but you can think of a receiving antenna as a time-reversed transmitting antenna: if you could make a video of the electromagnetic fields, a receiving antenna would look very similar to a transmitting antenna except the video is played backwards. So a clockwise rotation at the TX side becomes counter-clockwise on the RX side, which cancels out the fact that the antennas are facing in opposite directions (i.e. towards each other), so the direction of rotation ends up being the same on both sides. So in short, both the TX and RX side should use the same antenna polarization (LHCP or RHCP).

I don't fully understand the description of the second test - it sounds like the patch antennas are no longer facing each other. In that case you won't get much of a signal because you are outside the main beam of the antenna.

Last modified: Thu, 26 Jul 2018, 19:09 (GMT+1, DST)

In Quadcopters / Polarization:

Dcara55135

Comment #29: Thu, 19 Jul 2018, 1:24 (GMT+1, DST)

Quote


Here is an interesting observation I do not understand. I have 2 RHCP patch antennas.

1) I point the 2 antennas at each other (stright in line boresights) with one as Tx and one as Rx (1600 MHz). I observe only freespace path loss of the correct value for the distance (5 ft). I actually expected some rejection due to crosspol (maybe 20 dB?) thinking if it received RHCP it would transmit LHCP.

2) Believing now that the observation implied a Rx RHCP antenna would also Tx RHCP I moved the Tx antenna next to the Rx antenna (2ft away) facing the same direction as the Rx antenna (parallel boresights) so now the transmitted wave would be rotating opposite of the previous test and I would see the cross pol and beam width rejection. Alas it was not the case. In short, with the Tx antenna in this position facing the same direction as the Rx was facing showed 10dB more signal at the Rx antenna than when I turned the Tx antenna 180 degrees facing the opposite direction.

Do you have an idea of what is happening?

Last modified: Thu, 26 Jul 2018, 19:00 (GMT+1, DST)

In Quadcopters / Pagoda antenna:

Udon

Comment #30: Fri, 13 Jul 2018, 11:21 (GMT+1, DST)

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Hello
Pagoda antenna and Triple Feed Patch antenna
Which manufacturer is the best?