Or you can spend 2 extra dollars and get a chip with flash built in.

I did the math and 9600 baud is fine for 10Hz. My build thread has multiple test videos.

I already have a MT3339 chip
so I'm going with that first

and I have an Arduino for power (mini usb)
so that I can have it sent a commando to the GPS

I'll figure out the command eventually. I'll post it here.

therefore I would be very grateful
I had already found
"$ PMTK220,100 * 2F" (for the 10Hz setting)

Try sending this without the spaces (its hex):

B5 62 06 08 06 00 64 00 01 00 01 00 7A 12

Yep, thats the command:

I can not get that code in arduino

but
I've now done a battery in the GPS module
have the GPS module attached to the USB port
and miniGPS 1.4 I made connection
buad put the rate adjusted to 115200 and the update rate at 10Hz
Battery does he remember those settings

Arduino not necessary
though I would surely want Arduino at startup every time continues to set the GPS to 115200 and 10Hz
if in a few years the battery is dead I do not have to try and recall what it was

For future searching:

Reyax GPS Module
U-blox GPS Module
HC-05 10Hz GPS Module

HC-06 also works very wel (05 can search for Bluetooth devices, 06 can only respond)

What about adding battery to Bt-Gps?

Something like this:
I have found your article and want to try to build myself the same gps-receiver. Built-in battery would be a good addition. The possibility of charging from the micro-usb will be saved. Only I can not decide which batteries will even be enough for a couple of hours of operation?

I have order components on ebay and I can try only after a few weeks when they come to Russia =(

Sorry for my bad english and thanks for good and cheep gps-receiver!

That won't work.

I don't know exactly how Aidan has these things working, but I know they run on 5 volts. There might already be a small battery in there anyway.

That circuit there will switch 5V into 4.2 for lithium charging, that's easy. Expensive bit is converting 3.6V back to 5.0v.

If it doesn't have induction coil and decent sized capacitor it doesn't step voltage up. Needs to have these components, kinda like this one.

https://www.miataturbo.net/attachmen...ine=1454243078

That's a simple stepping boost circuit, doesn't step voltage down and won't charge batteries.

Min operating voltage of RYN25AI module is 3.5v(from specification).
Bluetooth module requires even less voltage.. (3.3v).

So do I need to step voltage up? Or it will be working with 18560 3.7v li-ion battery?

Have someone the opportunity to test the functionality of this design? Without converting 3.7V back to 5.0v.

I can hook one up to 3.7volts tonight and tell you. I looked into batteries, but decided for my purposes it wasn't worth it.

Is there any information on the 3.7v experiment?

Yeah i'll try and remember tonight.

I`ve recieved my moduls and test it with 3.3v of my usb to ttl board. It`s working!
Battery has not yet come. I decided to order a Li-Ion 3.7v battery type "14500".

I have some problems with RYN25AI. I change default params (1Hz to 10Hz, 9600 to 19200) and save config like example in this manual And all is working good for some time. But if I power off my device for a few hours all configs reset to default.

What I need to do, to save config forever?

You need to buy the version with the flash memory.

My board is RYN25AI with Max-7c chip on it. As on the first page of this topic. Do you use boards with Max-7 or Neo-7 chip?

P.S.: I realized that my chip is wrong and it is impossible to save the settings. I will think about to make the application for android, which would send the necessary initialization parameters at startup. But the question "what kind of chip you are using" is still relevant... I found two other variants RY725AI (with NEO-7N chip) and RYM25AI (with NEO-7M chip)

I did a writeup on making one of these. I told aidandj / SadFab, they didn't even seem mad. :likecat: In the writeup itself, I tried to make it very clear that it is not my idea and link to their original documentation, of course.

The main difference from the thingiverse page is that I went into a lot more detail on how to solder it up.

Writeup is here: sub-$50 DIY 10hz Bluetooth GPS Receiver - Did It Myself

I also wrote up how to set it to 10hz in detail: Setting Bluetooth GPS Receiver to 10hz - Did It Myself

I give 3 options. Using U-Center on Windows, a Python script I wrote, and then I also wrote an Android app that does it really conveniently: https://play.google.com/store/apps/d...10hzautosetter

I only tested it on my one chip, so I can't guarantee the app or script work everywhere. But they're free, so you get what you get. It does comply to the U-Blox spec, so it *should* work.

Sorry for necroposting, but thought it was most appropriate here. Hope it helps.

On the plus side, if you accidentally bought the wrong chip and can't permanently store settings, it's pretty easy to run my app just before your track day or whatever before opening racechrono/harrys.

Awesome write-up. We are always looking to spread our knowledge. I was too lazy to do a writeup like that so its good the information got out there. I'm going to link to it from our site to hopefully help people out in the future.