I am using 2 postcards, with lora radios, I have set low bandwith mode on the base and set defaults to logging and not turned on extra nmea messages over default. I find that most times my rover will either be in float or if it does get a fix it will age out to 120 seconds and drop out. How can I fix this?
So I’m wondering if my backyard maybe the signal is just not good enough. I have power lines and a tree and I’m remembering a time I tried to do static with a Trimble and couldn’t get a good static observation downtown. I’m using a survey tripod and multiband antenna. The longer it’s been cooking the longer I’ve seen fixes hold.
I just read this on the Quectel forum:
The maximum allowed time for injecting base station data into LG290P module is every 5 seconds
okay needed to copy off sd card to another place. Got a rinex made. now will it process is the next question.
The “maximum” statement isn’t extremely clear.
The LG290P can operate with Corrections older than 5 seconds.
It can also operate with 1 second corrections.
I’m afraid it’s not all that useful of a comment 
I am wondering if my backyard just causes it to kick in and out of rtk solution. Might need to try a big open field next.
Well I’ve now tried esp now and it works 1 second holding rtk, so the question is what Lora needs to function.
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How is your testing area? Does the rover antenna have a clear, unobstructed view of the sky?
My testing area is my backyard based on reading and using espnow I have determined it’s the Lora link crashing from being flooded. I have not tried using a fixed channel as was suggested to me so I will try that next.
I try in big open space and the base crashed for overheating maybe(feel very hot the baby helical base antenna) or the postcard has a problem working like base, when use like rover everything its ok, but in base mode crash, some times go from casting to xmitting and restart again.
I’m using the survey antenna on a pole for more accuracy. But I ordered some stick on heat sinks. Might be time to build a bigger case.
I will say I solved my Lora issue and now can get 2 postcards to talk to each.
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Congrats on getting RTK communication to work. would you share your configs? I am having no luck after about 4 attempts. I am using the LoraSerial Radios (Custom firmware for one-way communications: SparkFun_LoRaSerial/Firmware/LoRaSerial/LoRaSerial.ino.SparkFun_LoRaSerial.bin at tinker · cturvey/SparkFun_LoRaSerial · GitHub). From the LEDs on the LoraSerial units it seems that data is being transmitted and received. When I look at the output in a serial terminal from the LoraSerial I think the data looks ok ( I am a newb with RTK and I am not sure what a RTCM message looks like but I have read that it is binary… so I am hoping that the mix of gibberish and readable sentences are a good sign) . I have a portability shield on both the base postcard and the rover postcard. I give the base 10 minutes to survey in and it usually gets to a mean of 1/3 - 1/4 of a meter. after the 10 mins the shield on the base indicates it is sending corrections. Radios on both sides blink happily. Rover never indicates it a getting any correction data. Accuracy varies 1.25 Meters + on the display. No white LED anything. at this point I am thinking that the rover is not getting the corrections from the UART the LoraSerials are plugged into. in the field I generally use the Wifi Config screens but there is just not enough info or I am confused about ports/radios / correction data usage from the postcard perspective. Everything is on the latest firmware.
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First thing first I had to do was disable most the nmea messages in base mode on the one postcard, I then had to make sure the TX wire on the rover was disconnected because there is no flow control, i was able to hit 2000 feet with default radio settings. It was intermittent but I did not have LOS very good either.
Also make sure the baud rate is correct.
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