Eggtimer GPS 4K?

I did a search on "Eggtimer GPS 4K" and got no hits so sorry if I'm asking an oft' asked one.

I'm trying to get my Eggtimer TRS setup and am not sure what I am seeing. I power on the TRS then the LCD (receiver). After a few seconds I see "Eggtimer GPS 4K" on the LCD. I can't find reference to what that means in the user manual or the assembly instructions. I have performed the reset, "ctrl-y" with the USB cable, and it seems to have worked. However, I have yet to see the banner screen, "Eggtimer TRS 4N MY EGGTIMER TRS", on the LCD. Not sure what is not quite right. Anyone point me in the direction of documentation that gives more details or otherwise help-out?

Starting out with no drogue and no main to use the TRS like an Eggfinder with an LCD... I'll enable/use the other parts as I get comfortable.

Much thanks!,

Get the cable, make sure the EggTimer LCD is tuned to 915Mhz ID 0

Do the same thing with the EggTimer TRS. The instructions are pretty clear. If you can get both units on the same frequency and ID,
turn on the the EggFinder LCD. When it says "waiting for sync" turn on the TRS. It will beep once or twice and then sync with the LCD unit.

Make sure you have the connections correct on the USB cable when you are working with it as the Tx/Rcv lines are reversed on the TRS as opposed to the EggTimer. I found this out the hard way early on. Cris didn't realize the pads
were reversed on the TRS!:lol: If you do it by mistake, no harm is done. I have two TRS units and they haven't been gorked by me yet. (I've dorked a few EF's due to my rough handling but that's a different story.)

Cris is working on a Firmware update on the TRS to correct a quirk when using the TRS as backup drogue deployment. Not an issue if not doing that but you will want to have the capability to update the firmware. Follow the instructions on the site to get the update utility installed in your computer.
It takes a knack but I've had numerous update failures that eventually "take" without issue once I get the timing set.

I put header pins on all my ET devices on the reset pads. Makes it easy to perform the upgrades by opening the terminal. I actually use a twisted JST female plug and pull it out.

Note to Cris: You might want to enclose a few extra header pins like you do for the serial connection on the boards. Makes it easier to access the rst pads.:wink: Kurt

The last two digits on the first line are the firmware version of your Eggtimer TRS. "4N" would be 1.4N, the current version (likely to change in the next few days/weeks due to a bug noted on this thread). Yours says "4K" because you still have the 1.4K firmware (the previous release) on your unit. The second line ("MY EGGTIMER TRS") depends on what name you have programmed into your TRS. I don't recall if it actually defaults to that string, or if the default is empty since the first thing I did was customize mine. But if you did the ctrl-y and it worked you should have had an opportunity to enter a name, and what you'll see on the screen is:

Eggtimer TRS <version>
<your device name>

For me that's 4N and my email address, once the 1.4Q (the next expected FW version) firmware is released it would say "Eggtimer TRS 4Q" on the first line. The device name helps ensure that your LCD paired with *your* TRS, and not someone else's who happened to power-up on the same frequency around the same time (or I guess if you had multiple TRS's that you paired with the right one).

Much thanks!

I did get my TRS and LCD to switch over to 917 ID 7 earlier. I notice the power-up sequence sometimes "sounds" different and maybe if I want to re-synch I'll need to keep it powered-down for a while longer. Sometimes I see no LED activity on the xmitter board on the TRS on power-up. This makes me consider there may be something up with the controller curcuit, the no xmitter activity on power-up.

Interesting about the second line of the welcome banner. Mine is just black squares, not MY EGGTIMER TRS. I have not been able to edit that field (option ctrl-f, I think?) as it just shows up as black LCD squares and does not respond to backspace or delete or typed characters.

Interesting...

The original 4K release didn't initialize the Device Name field properly. Once you set it though (in the CABLED frequency/device screen, ctrl-f from the menu), it will be fine. When the new release is posted (probably later tonight) you NEED to download and install it... it fixes a deployment bug, and there's some interface changes that users suggested to me.

I will download and install it tonight or tomorrow. Much thanks!

Another question, (sorry, I'm full on 'em). When the TRS is in ready to launch mode and it emits a "tone", is that a wavering/variable warble sound? Mine sounds like it could be in "distress" but that may just be the "find me" tone?!? I've never been around a TRS in operation so I don't know what to expect exactly.

Thanks!

jrkennnedy2 said:

I will download and install it tonight or tomorrow. Much thanks!

Another question, (sorry, I'm full on 'em). When the TRS is in ready to launch mode and it emits a "tone", is that a wavering/variable warble sound? Mine sounds like it could be in "distress" but that may just be the "find me" tone?!? I've never been around a TRS in operation so I don't know what to expect exactly.

Thanks!

Click to expand...

It is especially noxious to be distinctive and heard through the airframe. If you don't hear it and the indications on the LCD receiver aren't right, don't push the button to launch. Ask any questions you can think of and don't be embarassed. Kurt

My observation is that the ready-for-launch tone varies during the periods where the TRS is actually transmitting on the radio (i.e. when the Hope module's TX LED lights, generally once per second with a longer pulse every 5 seconds when the satellite info is sent). Not sure if that's a voltage droop due to the transmission that affects the speaker tone in an audible way, or if it's just that the CPU is busy doing other things and it affects the waveform it was sending to the speaker. Probably more likely the latter.

I had one flight where the TRS power-cycled during the deployment event (still have no idea why, it was motor-eject so there was no load on the TRS battery). So while I lost the feed most of the way down (and all altimeter data post-eject), since the TRS automatically re-enters FLY mode (and sending GPS coordinates like a normal Eggfinder) if it doesn't find a LCD to sync with, I did get a fix on the final rocket position. Since it didn't detect a proper launch during descent it was still emitting the ready-for-launch tone once it was sitting on the ground. Having the TRS making the chirping noise helped even more in finding the rocket among the tall alfalfa in the field I launched at (so the ready-for-launch tone became a "find me" tone. I had asked Cris if the FW could be changed so that it could start chirping again once landing is detected and I got a positive response, though I don't get the impression that's been implemented so far. The StratoLogger similarly issues a locating 'siren' as a part of it's post-landing beep sequence which I've always liked.

Well, I thought I was going to update the flash on the TRS. However I cannot find the referenced link in the instructions for Win-AVR, "You
can get it by clicking on the link on the Eggtimer support page under Knowledge Base." Anyone got the link? I cannot seem to find a knowledge base under Eggtimer Support.

Figure I'd better get the right one.

https://sourceforge.net/projects/winavr/files/latest/download He has updated his site and it took a while to find it.

Guess I should have waited. Now my TRS says Eggtimer Build 1.04K. I thought I downloaded 1.05A? I seem to flash the TRS very fast and does not report errors.

That's the WinAVR site, you'll need that on your Windows PC in order to perform the flash.. You get the actual TRS software from https://www.eggtimerrocketry.com/attachments/File/Eggtimer_TRS_1_05A.zip . The flashing instructions are at https://www.eggtimerrocketry.com/attachments/File/Eggtimer_TRS_Flash_Update_Instructions(1).pdf .

Thank you to everyone who has offered me help!

Been trying flash this for the last hour. all I get is:

C:\WinAVR-20100110\bin>avrdude -Cavrdude.conf -v -v -v -v -pm328p -carduino -P\\
.\COM4 -b115200 -D -Uflash:w:c:\eggtimer_trs_1_05a.hex:i

avrdude: Version 5.10, compiled on Jan 19 2010 at 10:45:23
Copyright (c) 2000-2005 Brian Dean, https://www.bdmicro.com/
Copyright (c) 2007-2009 Joerg Wunsch

System wide configuration file is "avrdude.conf"

Using Port : \\.\COM4
Using Programmer : arduino
Overriding Baud Rate : 115200
avrdude: Send: 0 [30] [20]
avrdude: Send: 0 [30] [20]
avrdude: Send: 0 [30] [20]
avrdude: Recv:
avrdude: stk500_getsync(): not in sync: resp=0x00

avrdude done. Thank you.

The 3 "Send 0"s come out in less than .1 second! When I pull the jumper the TRS immediately goes into 3-beep (startup) mode. I can still connect to it using serial cable and serial connect program so the USB cable still seems to work and the TRS seems to be able to communicate over the USB.

ConnMan13 assembled it for me and did a GREAT job. But apparently I'm too slow to pull the jumper in time to flash it. Is there somewhere I can send it or should I just put it up for sale. VERY frustrated!

jrkennnedy2 said:

Thank you to everyone who has offered me help!

Been trying flash this for the last hour. all I get is:

C:\WinAVR-20100110\bin>avrdude -Cavrdude.conf -v -v -v -v -pm328p -carduino -P\\
.\COM4 -b115200 -D -Uflash:w:c:\eggtimer_trs_1_05a.hex:i

avrdude: Version 5.10, compiled on Jan 19 2010 at 10:45:23
Copyright (c) 2000-2005 Brian Dean, https://www.bdmicro.com/
Copyright (c) 2007-2009 Joerg Wunsch

System wide configuration file is "avrdude.conf"

Using Port : \\.\COM4
Using Programmer : arduino
Overriding Baud Rate : 115200
avrdude: Send: 0 [30] [20]
avrdude: Send: 0 [30] [20]
avrdude: Send: 0 [30] [20]
avrdude: Recv:
avrdude: stk500_getsync(): not in sync: resp=0x00

avrdude done. Thank you.

The 3 "Send 0"s come out in less than .1 second! When I pull the jumper the TRS immediately goes into 3-beep (startup) mode. I can still connect to it using serial cable and serial connect program so the USB cable still seems to work and the TRS seems to be able to communicate over the USB.

ConnMan13 assembled it for me and did a GREAT job. But apparently I'm too slow to pull the jumper in time to flash it. Is there somewhere I can send it or should I just put it up for sale. VERY frustrated!

Click to expand...

I can do it if you send it back to me. PM me.

switch the green and white wires on the cable and try again. Kurt

Is there any way to tell on the LCD-GPS whether the GPS chip on the LCD board is working without having the GPS tracker powered up? All the tests seem to say that the mini needs to have power, but so far I only have the 4AA pack for the LCD hooked up.

And what kind of little battery chargers are folks using for these small 2S lipo batteries? I assume something that plugs into a USB.

If you’re using a 2S Lipo you probably want a balanced charger. Something like this:
https://hobbyking.com/en_us/imax-b6ac-v2-professional-balance-charger-discharger.html

OK thanks I ordered that charger up.

I hooked the Mini up to the LCD and programmed it to frequency etc tonight. RF LEDs lit up so seems like it is responding appropriately when powered by the LCD AA 4-pack.

I have mini batteries but they are only 30% charged and no charger for the moment, so I haven't tried plugging them into the mini in "RUN" mode yet.

The LCD seems to go through the proper sequence and detects its GPS module and proceeds to "Waiting for Fix" pretty quickly when outdoors, so according to the manual it is getting a GPS fix.

So I guess the only question is whether the GPS part of the mini is working, since that does not seem to be tested when powered by the LCD. I soldered the LCD and LCD-GPS boards first, so if they are getting a fix then I suspect the mini soldering may actually work also.

I didn't realize this was a solder kit when I bought the stuff and I had never soldered any electronics before so if it all works straight off the bat I will be somewhat amazed. I used a soldering station I bought at an RC hobby place. TrakPower TK 950. Good temp control but the tip included was just a bit too large for some of the GPS leads and it was too big to reach the bottoms of the little solder trenches on the back of the GPS board. So I really had to melt them open a bit. Anyway so far so good on the power up.

Lost my White Wolf on its second flight with a 29mm H128 or similar out at Salome airfield near Phoenix just after the new year trying a level 1 cert. I had the eggfinder kit and the 3D printed nosecone mount but had not soldered it together in time for the flight waiver weekend, so I just went for it and watched it rocket off into the low cloud cover never to be seen again. Should have gone about 3500 feet. Wind was calm but going a different direction at ground, 1000, 2000 and 3000 feet. Plan to get another little 38mm airframe, either AMX or other but definitely not going further without some better retrieval technology.

The only weird part of this eggfinder build has been the case. The LCD hole location instructions seem to be off by about 1/4". I plan to order the $20 3d printed case and put it inside that.

Thanks we live in LA but go to Phoenix to visit the grandparents and sometimes the timing works out to launch some rockets with SSS.

Gosh that sounds like a lot of soldering! I can see people needing a bit of help though. Kind of a steep learning curve. I just kept telling myself that if I can TIG weld aluminum, I can figure this out. Mostly just getting accustomed to the small scale and figuring out the proper equipment to use for the job.

Keep an eye out for the White Wolf 38 Flight sim had it landing within 1000 feet of the launch pad, but winds aloft may have been higher. It will be a fun find for someone. I ran out of time and no bicycle or drone. Nothing like wandering around in the scrub brush for hours to cap off a weekend. Nick Estes was there so please tell him thanks again from me for all his help. Super guy.

That charger and the Turnigy batteries are both working great with the mini.

I thought I had programmed the mini to run on 909 rather than 915, but the LCD didn't pick it up until I switched the mini back to 915. I might have plugged the mini into the wrong connection on the LCD; the bottom of my board has a four prong and a three prong connector, and I used the four prong. Perhaps I should try the 3 prong board connector for the LCD GPS unit instead, and hook the mini up to it for programming.

Now just need to epoxy the GPS anntennas to their shields and find some clear shrink wrap, as I seem to have lost mine.

I also need to figure out what rocket to replace the white wolf with. Maybe a Wildman blackhawk. I liked the Wolf a lot though - pretty well built and simple. Only downside is trying to get the Jolly Logic to deploy reliably out of a 38mm tube, as it is a bit snug in there. I plan to put the GPS into the nosecone, so having a nosecone that is open in the back with provision for removable bulkhead would be a step up from the White Wolf.

You use the top three pins of the 4-pin connector for programming the Mini from the LCD receiver... see the procedure at the end of the Eggfinder Mini Assembly Gude ( https://eggtimerrocketry.com/wp-content/uploads/2018/10/Eggfinder-Mini-Assembly-Manual-A7-Pics.pdf ) . Note that the picture shows the older LCD board that doesn't have the extra 3-pin connector for the LCD-GPS Module... the connection is the same if you have the newer board.

OK great. Thank you. I am not sure why the mini did not take the new frequency. Is there any way to confirm when it has been re-programmed? Or perhaps I missed a step to get it to stick. I just powered it up from the LCD, reprogrammed the LCD, moved to the end of the menu, and powered it off. Maybe I need to press the button again to exit programming mode?

Yes the instructions are a bit confusing as the newer board has a three prong that is intended for GPS connection, and not mentioned in the instructions. A sentence telling people with the newer board to still use the 4 prong for programming the mini would probably prevent some calls/forum posts.