MDRA Rockets Red Glare GPS Frequency Tracking

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Since there is nothing official being done to track what frequencies are being used, I figured I would start a thread for those of us going to Red Glare. Post your device, its name (if applicable), the frequency it uses, the day you plan to fly on, and your name. I will try and keep a chart in this main post updated as people comment their frequencies. I've filled in my info below as an example.

Device TypeDevice Name (If Applicable)FrequencyDay(s) Planned for UsingUser
Featherweight GPSFthrWt02748Ch13B 912.600MHzFridayTrevor Mushung
Eggfinder Mini919MHz Ch6FridayAndrew Steele
Eggfinder Mini909MHz Ch3Saturday & SundayMicah Hanson
Eggtimer Telemetry unitWraith1919MHz Ch3Saturday & SundayMicah Hanson
Eggtimer Telemetry unitSilverGhost1919MHz Ch3Saturday & SundayMicah Hanson
Eggfinder GPS433.050MHzSaturday & SundayRobert Kaplan
Featherweight GPSFthrWt02712CH25A 922.200MHzKevin Mcgee
Eggfinder Tx917MHz Ch1Friday & SaturdayJeremy Wong
Eggtimer Quantum923MHz Ch1Friday & SaturdayJeremy Wong
Eggfinders911MHz Ch7Brian Schenkenberger
Featherweight GPSke8nai_sCh25A 922.200MHzFriday
Featherweight GPSWMXCh22A 919.800MHzSaturday & SundayJustin Gleiter
Featherweight GPSConcept 125Ch22A 919.800MHzSaturday & SundayJustin Gleiter
Eggfinder921MHz Ch6All 3Jeff Miller
Eggfinder921MHz Ch7All 3Jeff Miller
Eggfinder913 Ch3All 3John Banks
Eggfinder913 Ch5All 3John Banks
Homebuilt GPSRitz1433.240MHzAll 3John Ritz
Eggfinder911MHz Ch3FridayWalt Rauscher
Eggfinder919Mhz Ch0FridayMarten Beels

I will only be there on Saturday. If someone wants to print this out and bring it on Friday feel free to. Otherwise I will bring a printed version for the RSO table on Saturday and leave it for Sunday. I will also be posting this on the MDRA FB group and the Tripoli group, I ask that you please try not to post the same information on multiple posts please.
 
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Thank you for doing this. I had posted about this on the MDRA Facebook page and then forgot to follow up.
Here are mine:
Eggfinder Mini GPS TX, Frequency 909MHz, Ch3, Saturday and Sunday, Micah Hanson
Eggtimer Telemetry Unit, (Wraith1), Frequency 919MHz, Ch3, Saturday and Sunday, Micah Hanson
Eggtimer Telemetry Unit, (SilverGhost1), Frequency 919MHz, Ch3, Saturday and Sunday, Micah Hanson

Thanks again.
 
Here are mine:
Eggfinder GPS TX, Frequency 433MHz, Saturday and Sunday, Robert Kaplan
 
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Flying Friday , named: ke8nai_s, featherweight tracker on channel 25a 922.200
Thanks for doing this:
Featherweight GPS; Device Names: WMX, Concept 125; 919.800 Ch 22A; Sat & Sun
Can I get a name to put on? This will be printed and be up at the RSO table so it would be nice to have names incase contact needs to be made.
 
@kevin.mcgee @ke8nai Looks like you two have the same tracker frequency set. If you two are flying at different times then it should be fine, but I would recommended you two get in contact to avoid a conflict.


List is updated again including FB comments. It is coming along nicely and I will be bringing a paper version of this that will be printed out with a chart for Saturday and a separate chart for Sunday. I'll sort out the split charts on Thursday (30th) and then print them out before I travel.
 
Updated again. It is interesting seeing the amount of trackers that are being used and the distribution between brands (or lack thereof in this case)
 
Device TypeDevice Name (If Applicable)Frequency Day(s) Planned for UsingUser
Hounddog GPS LoRa Homebuilt Arduino Ritz1 433.240 Mhz (200kHz bandwidth) Fri-Sun John Ritz

1679703355102.png
 
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Walt Rauscher Flying Friday - using Eggfinder on 913MHz, ID = 3
This will be in a LOC IRIS 2.2" and a LaserLOC223, both flying on H motors.

I see John Banks is running same Freq & ID.
I may change the ID before Red Glare to not match John's.

I think it will be a good idea to put our Cell phone number on the Frequency sheet at the RSO table.
This will make it easy to find and check if the other person on same freq is currently flying.
 
I see John Banks is running same Freq & ID.
I may change the ID before Red Glare to not match John's.
If you do, please let me know and I'll update this chart.
think it will be a good idea to put our Cell phone number on the Frequency sheet at the RSO table.
This will make it easy to find and check if the other person on same freq is currently flying.
At least with names the RSO could make an announcement if needed. I will leave it up to others if they would like to add their phone numbers at the field. I will make sure there is space on the table for those that wish to.
 
If you do, please let me know and I'll update this chart.

At least with names the RSO could make an announcement if needed. I will leave it up to others if they would like to add their phone numbers at the field. I will make sure there is space on the table for those that wish to.
I changed the Eggfinder freq to 911MHz, ID =3
Now John and I are on different freqs.

This thread is a great idea.
 
Thanks for posting this, great idea. I've got an Eggfinder mini on 919 MHz ID Code 0 and I'm planning on flying Friday. Does this mean I have a potential interference issue with Andrew Steele on 919 Ch 6? I'm not quite sure of the distinction between ID codes and channels.
 
Here are mine:
Eggfinder GPS TX, Frequency 433MHz, Saturday and Sunday, Robert Kaplan
Note that 433.000 (actually 433.050, there's a 50 kHz offset so it's centered in the channel) is the default... I recommend that you change it in case somebody else shows up with one on the default. You have 299 other frequencies to choose from...
 
Thanks for posting this, great idea. I've got an Eggfinder mini on 919 MHz ID Code 0 and I'm planning on flying Friday. Does this mean I have a potential interference issue with Andrew Steele on 919 Ch 6? I'm not quite sure of the distinction between ID codes and channels.
IIRC channel is basically the decimal point after the 919. So 919.050 would be Ch0 (I think). So no you don't have a conflict. Also can I get a name to add to the sheet?
 
Thanks for posting this, great idea. I've got an Eggfinder mini on 919 MHz ID Code 0 and I'm planning on flying Friday. Does this mean I have a potential interference issue with Andrew Steele on 919 Ch 6? I'm not quite sure of the distinction between ID codes and channels.
The way I understand this is that your Eggfinder receiver will receive both your and Andrew's GPS transmissions but will ignore Andrew's with an ID = 6 and only display coordinates from your GPS with an ID = 0.

The ID is not a channel but a code in the data packet.

I am surprised that Cris didn't answer this.
 
The way I understand this is that your Eggfinder receiver will receive both your and Andrew's GPS transmissions but will ignore Andrew's with an ID = 6 and only display coordinates from your GPS with an ID = 0.

The ID is not a channel but a code in the data packet.

I am surprised that Cris didn't answer this.

That's what I thought as well. They'll be on the same frequency, so there is a chance of interference of they transmit at the same time, but as long as they don't transmit at the same time, the transmissions without the right ID code will be ignored.

@cerving , can you confirm if this is correct?
 
For the 900 MHz units, the ID (channel number) is a 250 kHz offset from the base frequency, so 919/3 is 919.750 MHz. Each ID is over twice the receiving bandwidth away from the adjacent one... you will not pick up any data from any Eggfinder that is not on your exact frequency/ID combination.

Note that the 70cm units don't use the same scheme... the frequencies are 100 kHz apart, with a 50 kHz offset so they're centered in the middle. With a 50 kHz bandwidth and 100 kHz spacing, you're not going to see adjacent channel data.
 
For the 900 MHz units, the ID (channel number) is a 250 kHz offset from the base frequency, so 919/3 is 919.750 MHz. Each ID is over twice the receiving bandwidth away from the adjacent one... you will not pick up any data from any Eggfinder that is not on your exact frequency/ID combination.

Note that the 70cm units don't use the same scheme... the frequencies are 100 kHz apart, with a 50 kHz offset so they're centered in the middle. With a 50 kHz bandwidth and 100 kHz spacing, you're not going to see adjacent channel data.

Thank you Cris! That clears that up.
 
Yes, Thank you Cris. This was never clear in the Eggfinder manual and seemed to be a data packet ID rather than an offset of the TX frequency.

I'm going to need to play with setting different IDs and look on a spectrum analyzer to see exact center freq used.
Just looked at my mini GPS on spectrum analyzer and 911MHz, ID 3 is at 911.750MHz.
Bandwidth is about 125 kHz
 
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