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In SimpleScreenRecorder / Translations:

Cges30901

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

Quote


Hi Maarten,

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

In Quadcopters / Triple Feed Patch antenna:

Dave

Comment #2: 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 #3: 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 #4: 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 #5: Tue, 30 Oct 2018, 1:28 (GMT+1, DST)

Quote


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 #6: 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 #7: 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 #8: 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 #9: 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 #10: 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 #11: 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 #12: 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 #13: 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 #14: 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 #15: 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 #16: 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 #17: Fri, 13 Jul 2018, 11:21 (GMT+1, DST)

Quote


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

In SimpleScreenRecorder / Troubleshooting:

Jorge

Comment #18: Fri, 29 Jun 2018, 21:34 (GMT+1, DST)

Quote


Quote: Jorge

Hi. I want to record video conferences. However I cannot record both my voice and the voice of the other person. When I select source `Headset H390 Analog Mono`, it only records my voice. When I select source `Monitor of Headset H390 Analog Stereo`, it only records the other person's voice. Since this is probably a common use case, could you provide easy instructions for it?

Hi. I solved it myself through the help of the following easy tutorial:
https://www.linux.com/learn/weekend-project-record-skype-calls-and-other-apps-linux

Regards

In SimpleScreenRecorder / Troubleshooting:

Jorge

Comment #19: Tue, 26 Jun 2018, 23:31 (GMT+1, DST)

Quote


Hi. I want to record video conferences. However I cannot record both my voice and the voice of the other person. When I select source `Headset H390 Analog Mono`, it only records my voice. When I select source `Monitor of Headset H390 Analog Stereo`, it only records the other person's voice. Since this is probably a common use case, could you provide easy instructions for it?

In Quadcopters / Triple Feed Patch Array antenna:

Maarten Baert

Administrator

Comment #20: Sun, 24 Jun 2018, 21:13 (GMT+1, DST)

Quote


Quote: Androot

Hello

I have qustion about part 2 (bigger one).
I opened it in Kicad Gerbviewer and found that bottom copper layer has additional ground plane. On photos there isn't. It's some improvement or error in Gerber file?

Best regards
Piotr

This is explained below the photo:

Quote

The photos above show a prototype, the latest design files have an additional copper plane on the back. This copper plane doesn't have any function, but it helps to balance the amount of copper on the top and bottom side of the PCB, which should reduce warping.

In Quadcopters / Triple Feed Patch Array antenna:

Androot

Comment #21: Fri, 22 Jun 2018, 10:02 (GMT+1, DST)

Quote


Hello

I have qustion about part 2 (bigger one).
I opened it in Kicad Gerbviewer and found that bottom copper layer has additional ground plane. On photos there isn't. It's some improvement or error in Gerber file?

Best regards
Piotr

Last modified: Fri, 22 Jun 2018, 10:02 (GMT+1, DST)

In Quadcopters / Triple Feed Patch Array antenna:

Actuna

Comment #22: Thu, 21 Jun 2018, 20:25 (GMT+1, DST)

Quote


Hello ...

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

Manufacturer: ACTUNA

URL: https://actuna.com/Antenna-Triple-Feed-Patch-Array-TFP-A-p22197

Price: 26,32 $

- hybrid
- SMA (female)

Notes: Each antenna is measured individually and gets its own parameters tab. Optional 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.

In Quadcopters / Pagoda antenna:

Maarten Baert

Administrator

Comment #23: Sat, 16 Jun 2018, 16:58 (GMT+1, DST)

Quote


Quote: Hotmultimedia

Was the antenna designed with that 3D printed plastic cover? How does it affect it's operation?

I don't have anechoic chamber measurements of the antenna with cover, but you can see some VNA measurements here.

In Quadcopters / Antennas:

Maarten Baert

Administrator

Comment #24: Sat, 16 Jun 2018, 16:56 (GMT+1, DST)

Quote


Quote: Hotmultimedia

Hi. Can you recommend an antenna simulation software?

I'm wondering if it would be possible to design an atleast somewhat operating 5.8GHz antenna that would be embedded within a wooden block.

I use HFSS. CST is also good. Both are too expensive for hobbyists though, I can use it through my university.

You can't really embed a 5.8GHz antenna in a wooden block, the absorption of the wood is way too high.

In Quadcopters / Pagoda antenna:

Hotmultimedia

Comment #25: Fri, 15 Jun 2018, 9:26 (GMT+1, DST)

Quote


Was the antenna designed with that 3D printed plastic cover? How does it affect it's operation?

In Quadcopters / Antennas:

Hotmultimedia

Comment #26: Wed, 13 Jun 2018, 22:29 (GMT+1, DST)

Quote


Hi. Can you recommend an antenna simulation software?

I'm wondering if it would be possible to design an atleast somewhat operating 5.8GHz antenna that would be embedded within a wooden block.

In Quadcopters / Triple Feed Patch antenna:

Maarten Baert

Administrator

Comment #27: Fri, 1 Jun 2018, 1:43 (GMT+1, DST)

Quote


Quote: Prouser27

Hello Maarten!

On the vertical cross-section image it looks like as the LHCP is more "stronger" as the RHCP polarization? The LHCP polarization looks like an big signal bubble in on direction and the RHCP much smaller.

Or are the two polarizations equally strong?

The images show the radiation pattern when a signal is applied to the LHCP port and the RHCP port has only a 50 ohm terminator connected to it. It's not supposed to transmit any RHCP radiation. If you swap the signal to the other port, LHCP and RHCP will be swapped as well. So LHCP and RHCP are equally strong, at least when using the right port.

In ExtremePhysics / Collision filtering:

Maarten Baert

Administrator

Comment #28: Fri, 1 Jun 2018, 1:41 (GMT+1, DST)

Quote


Quote: 7upnamk

Hi maarten. I never work with bitwise operation before so that i've been confused so much with your destructible terrain example. In the terrainblock_init script, i cant understand this:

mask = (1<<(size+1))|1;

why do you add

|1

into this? I've tried to comment like this

mask = (1<<(size+1))//|1;

and it still worked.
Sorry about my bad english
Thanks so much for your effecient extension!

If I recall correctly I did that because I use the least significant bit for collisions with regular objects. However ExtremePhysics is set up in such a way that if at least one of the two objects has a collision mask bit in common with the other, a collision will happen, so removing that bit does nothing in this case. However if you removed it as well for the regular objects, they would no longer collide with the terrain.

The (1<<(size+1)) part is used to quickly find all terrain boxes of a certain size.

In Quadcopters / Triple Feed Patch antenna:

Prouser27

Comment #29: Wed, 30 May 2018, 14:48 (GMT+1, DST)

Quote


Hello Maarten!

On the vertical cross-section image it looks like as the LHCP is more "stronger" as the RHCP polarization? The LHCP polarization looks like an big signal bubble in on direction and the RHCP much smaller.

Or are the two polarizations equally strong?

Last modified: Wed, 30 May 2018, 14:50 (GMT+1, DST)

In ExtremePhysics / Collision filtering:

7upnamk

Comment #30: Wed, 30 May 2018, 6:09 (GMT+1, DST)

Quote


Hi maarten. I never work with bitwise operation before so that i've been confused so much with your destructible terrain example. In the terrainblock_init script, i cant understand this:

mask = (1<<(size+1))|1;

why do you add

|1

into this? I've tried to comment like this

mask = (1<<(size+1))//|1;

and it still worked.
Sorry about my bad english
Thanks so much for your effecient extension!