LPS8 and LDS03A - Range

Mis packs, and even misconfigured builds, are not unknown in the industry! I bought a bunch of 868Mhz EU TTIG’s a while back and 1 just refused to work - box was correct, label on device was correct…only when I ripped apart and trashed it did I see a tiny SMD resistor on the edge of board showing 915 vs 868 config! S4!t happens :slight_smile: (Yes I got a refund!! :wink: )

@Jeff-UK - ok this is the cfg from the AT+CFG command: (blanks were removed by me like keys etc)

It shows a US915 at least hardware wise.

AT+DEUI=a8 40 41 2e 91 84 7e ec
AT+DADDR=01 84 7e ec
AT+APPKEY=
AT+NWKSKEY=
AT+APPSKEY=
AT+APPEUI=a8 40 41 00 00 00 01 01
AT+ADR=1
AT+TXP=0
AT+DR=0
AT+DCS=0
AT+PNM=1
AT+RX2FQ=923300000
AT+RX2DR=8
AT+RX1DL=1000
AT+RX2DL=2000
AT+JN1DL=5000
AT+JN2DL=6000
AT+NJM=1
AT+NWKID=00 00 00 00
AT+FCU=0
AT+FCD=0
AT+CLASS=A
AT+NJS=0
AT+RECVB=0:
AT+RECV=0:
AT+RJTDC=20
AT+RPL=0
AT+VER=v1.1 US915
AT+CFM=0
AT+CFS=0
AT+SNR=0
AT+RSSI=0
AT+TDC=7200000
AT+PORT=2
AT+RX1WTO=14
AT+RX2WTO=7
AT+PWORD=123456
AT+LEAPSEC=18
AT+SYNCMOD=1,0
AT+TTRMOD=0
AT+CALCFLAG=0
AT+DISALARM=0
AT+TTRIG=0,0
AT+MOD=1
AT+TIMESTAMP=2021-11-12 T00:21:28
AT+CHS=0
AT+CHE=0
Use default channel

Ok why you no listen! ? That is just S/w and output from S/w - the device will do what you tell it to do and could be that though a 915-923 h/w build it was programmed/configured with US915 firmware it still wont work as a 905.3Mhz device with any efficiency - as evidenced by your abissmal RSSI figures…I would be inclined to go with the label on the module as likely a mis pick for the subsequent build of the node system - sorry can’t say/advise any more other than get it replaced with a known good/confirmed US915 device - possibly a cheap unit from an alternate manufacturer so you know we arent all going mad :slight_smile:

lol - I promise I’m listening - steep learning curve here as I’m totally new to this. I can see about a different manufacturer for another node. Is there a recommended brand that everyone really likes? I’ll need a US915 node of course. Any help on sourcing will be much appreciated. Thanks again for all the help and hanging in there with me!

Actualy yes… Dragino! :rofl: we often recommend the cheap door sensors as a simple low cost device test operation! :slight_smile:

forum search will yield many devices…

So I picked Dragino and this is how it’s going to be - lol - I’ll do some digging for another device. Thanks as always!

The really tricky thing for a recommendation is not knowing what you have available. There’s plenty out there at a reasonable price, but if it’s in the EU or the Far East, the carriage may tip it in to ‘expensive’. So probably best for you to get a short list of what you can get locally and check back in here for a bit of a vote.

I ended up grabbing one of these. LoRaWAN Door Sensor | Dragino LDS02 Helium | CHOOVIO USA

We’ll see where it goes. :slight_smile:

I got the LDA02 in yesterday - and setup - same results. I’ve been working with Dragino - they have looked at pics of both the LPS8’s I have (internal pics) as well as pics of the lds03a’s I have. They said the lps8’s look correct.

I’ve tried turning off wifi, turning off my philips hue and my zwave network - no change. Rssi is still in the -120-130’s - see screenshot for the lda02 attached.

image

Time to take it somewhere way out of range of the other RF devices to eliminate any possibility of interference.

Agreed - I was thinking quite similarly. I’ll see if I can do that sometime today and report in.

Ok I moved the lps8 to my barn (all wood sides - metal roof) - and took the lda02 with me to test. The barn is 30 by 30 - so I had the gateway on 1 side and the lda02 about 20’ from the lps8 - see results. No difference. :confused: The lps8 is setup for band 2 - just a quick note -

image

image

An RSSI of -131 and an SNR of -12.8 sounds like very weak signals, long distance or poor or no antennas, faulty modules etc.

If interferance was a major issue you might expect the SNR to be poor, but with a stronger RSSI.

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roger - and considering there is no antenna for me to mess with on the lds02 - and it’s brand new out of the box - I’d assume the problem has to be on the lps8’s end. I 120% made sure not run the lps8 without the antenna. It was new, sealed in the box when I bought if off ebay. I made sure the antenna on the new lps8 (and the used one I bought before as well) are as hand tight without being crazy about it, tight on the unit. 3 nodes, 2 gateways and all show the same issue. I’m so puzzled. Thanks for hanging in there with me everyone - I sure do appreciate it! I’m also in contact with Dragino as well in the background.

Can I try one of the antennas from the lds03a on the lps8 gateway or will it damage anything. I tried twisting it on (with no power) and noted it seats much further than the stock antenna that came with the lps8

The black antenna is off the lda03a

The white one is the stock that came with the lps8 - note the gap.

20221023_124458

20221023_124530

In theory yes…. It will depend if sma male, sma female or rp-sma m or RPi-sma f……. A picture paints a 1000 words! Gap irrelevant as will depend on the specific mechanical design of any given ant……

I gave it a shot - put the lds03a ant on the lps8 - no change…in fact, somewhat worse - I had to stand like 2 ft from it to get it to send anything to the gateway.

image

You need to switch to CHE=2. Your node is currently using 64 channels where the gateway listens at only 8.

This should be CHE=1 for 8 channel mode.

I noticed all uplinks you show are at the same frequency (905.3), the last one of the channels used by TTN. It is almost like your nodes are using the next set of frequencies. Check if your nodes use the frequencies listed at https://www.thethingsnetwork.org/docs/lorawan/frequency-plans/

@kersing - I was super excited - I thought you were on to something here - but same after setting lds03a to AT+CHE1

image

From the serial of lds03a -
image

@kersing - also with AT+CHE=2

image