I have to second the RFM69 modules over the NRF modules. I was struggling to get more than about 7 metres in open air on the NRF modules that I had, however swapping over to trying the RFM69 modules for me will get me 30m distance through 2-3 brick walls with no hassle at all. I haven't looked back :)

Capacitive switch sensor like the AT42QT1011 maybe?

Something along the lines of https://www.sparkfun.com/products/14520

Only thing I'm not sure of is whether the copper wire would trigger the capacitive sensor, although if its being inserted by hand then it should have a charge from your own bodies natural charge as well possibly? Or if it is being fed a charge by something else that is touching it, then it might be enough.

@sundberg84 Thank you so much for the advice, I knew that it would come down to small things here and there, and it's so much easier to tinker around in eagle than try to order a board, find the errors and fix/reorder over and over, so I appreciate it very much!

Time to get back in and make some changes :)

Good evening!

I have been doing some bits and pieces, built a few temperature sensor nodes that are happily collecting information throughout the house.

I wanted to turn my attention to designing some in-wall modules, as I have a specific light switch for my garage that the builders decided to put in a very odd spot, its on the wall right in the middle of where one of our car bonnets end up, so you have to lean across the car just to turn the lights on!

So this is the first module I have ever designed, its done in EAGLE, with a combination of imported libraries for things like the HLK-PM03, and I have modified a pro-mini 3v3 layout to remove some of the pins that I won't use in this project, to try and keep things a little easier to route.

This is also the first time I have done PCB work with 240V power, so I would appreciate any comments that you might have!

One thing to note is that currently there are just mounting holes for the Live and Neutral inputs, I haven't yet decided on the terminals for those, I'll have to pop down to Jaycar Electronics during the week and pick up some samples for measurement so that I can make a footprint for them. Also, the Serial Upload pins shown in the image are just because I didn't get around to removing them from the design, I would still have them on the end product, but I would spin them around so they run over the top of the pro-mini board.

Many thanks to everyone on the "Safe in wall ac/dc converters" thread, that has been very invaluable for research!

I know that I haven't got any voids in the board to section off the AC traces, that is my next learning experience too :)

Some things to consider, will be that I will have a capacitive switch sensor for the 3 pin header, I will mount that behind a blank faceplate, and have the LED lighting up the faceplate. Further versions will have more than one switch sensor and LED, this is just to get an idea of size and how well it fits behind a wallplate. I'm also using the HLK PM-03, which gives a 3v3 output, so I don't have to bother with voltage regulation for the RFM69, and the capacitive buttons are happy with a 3v3 input too, with no degradation in range/sensitivity.

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Thats kind of where I'm stuck, I'm not sure what to put on to help it, whether its just that the power circuit is slightly higher output voltage than it would normally get from a battery pack or whether I need to have something else added in....Creating these circuits (While somewhat simplistic) is a bit of a first for me, so still learning as I go :)

Hi guys... I've been hunting around and hoping that you can give me a solution to my issue! Being christmas, we do a fairly big display at our house (Its a huge thing in Australia!).

I have some solar lights that have worn out over the years, so when the solar controller gets into pretty bad shape, I just knock up a little voltage converter to drop a 5v power source down to about 3V to power the solar lights, and give them a new life, not to mention that I can also turn them all on and off by the same power switches, rather than hunting for all the individual switches out in the garden lol.

I'm a little stumped though, because I have a couple of sets of solar stars that flash, and they would cycle in a roughly 2 second on/off pulse on solar, but now that I've converted it to low voltage mains, it becomes a half second on, 3-4 second off cycle now. I'd prefer to keep them to the same cycle if I can, as now they don't really show up very well.

I have seen some references to the flash being a result of the batteries internal resistance, so I might need to add something to my circuit, but I'm not sure what.... that's where I got stuck.

The circuit is a really simple LM317 with 2 resistors to drop the incoming 5V down to 3V, which then just feeds into the input side of the original light controller, so essentially it replaces the solar panel and the battery inside the compartment.

Any tips? :)

Not so much cost as an issue, but more being able to pack things into small size requirements, such as light switch casings or junction boxes. I'm happy to use phone chargers for some sensors, but things like light switch sensors and garage or outdoor sensors I need sealed options.

Got an email today from Mouser about a new series of AC/DC modules, and wasn't sure how the idea would compare to things like the HLK units that we are starting to see used.

The package details are at http://au.mouser.com/new/cui-inc/cui-pbo-3-pbo-5/

I'm still fairly new in electronics design, so some of it goes over my head, but on that page they have the diagrams with the application circuits. Does that design mean that in order to use this module, you would need the module itself, PLUS all of the fuses, varistors, caps etc in that application note? Does that then mean that this module would be analogous to just the HLK module on its own as well?

I think this is the reason I haven't yet gone down the route of sensors powered directly from AC (As much as I want to!), is that there doesn't really seem to be a pcb module that has everything included.

@manutremo said in RFM69 range issues:

Hi @executivul ,
You mentioned in your post that the length of the antenna must be tuned to the circuit - would you mind sharing the process to do the tuning?

https://www.mysensors.org/build/connect_radio

Down near the bottom of the page is the lengths of antenna needed for the three primary frequencies used by the RFM board.

Isn't that what the network ID is for though? I thought the network ID was the channel number within the band....or is it more analogous to the SSID in a WiFi type network?

How many thumbs do you require to create one switch? Is there a good thumb to wheel ratio that makes for a good switch? Would you make the switch out of different wheels, say light passenger vehicle versus a late 16th century cart wheel? Would you be able to specify the amount of each type of wheel in the production of said switch? How about thumb types? Can I have one switch made from virgin female thumbs, and would it be more expensive than one made from 50 year old retired carpenter thumbs? I would have thought the carpenter thumbs would be more expensive than virgin female thumbs, as most retired carpenters have lost part of their thumb by the time they retire, so would be quite rare to obtain.

TL:DR, your products suck, and have been blacklisted from my stock ordering options too. So long!

Many thanks @tbowmo I'll sit down tonight and fire up the iron, looking forward to freeing up another pro-mini back into the pool for more sensors!! :)

Hi guys!

So my shiny little Sensebender gateway arrived today in the post, man am I excited!

Just had a question, I need to solder the RFM69 to the underside of the module, but I have never done that kind of overlay solder before, and just wanted to check. do I need any insulation between the RFM and the sensebender? Or does the green mask provide for the electrical isolation? So, do I just lay the RFM onto the sensebender and solder the pads?

And I'm guessing I still need to have the antenna wire soldered on to the RFM, even though there is a corresponding pad on the sensebender underneath the antenna pad on the RFM.

I have had the same issues as you with the RFM69 modules.

First ones that I bought were marked as RFM69HCW 433mhz, and when I put them together as required, I couldn't get range of more than around 40cm. After that, the reception dropped off a cliff. One thing I did note was that the modules looked different from all the images I could see on this site, which led me to ponder whether I just had crummy modules or not. Also, given the size of the antenna, I was a bit loath to continue with 433mhz radios.

so I decided to up and pick up a new batch of radios, and change over to the RFM69HW (without the C), 868mhz. These ones, when I soldered them up, give me range of around 30m through the entire length of the house, through every wall.

So the only thing I could put my effort down to was that I just had a crummy radio module batch first, and a proper set later, so not sure I can put too much more knowledge into things here.

@NeverDie

@NeverDie said:

Strange. Here the shipping cost is $16.45.

Wow, wonder if its because I'm in Western Australia, that final step over the Nullarbor taps on another $135.00! :)

I thought it looked really good, until I saw the shipping costs of 3/4 of the price of the printer to get it to Australia! Ack! Back to the drawing board :)

Strange question possibly, but for modules like the RFM69's, do I have to have a fly lead to BOTH grounds? Or just one of them?

Hi guys,

I have built a couple of nodes that I'm trying to slowly add to, so wanted to start with just an arduino nano, level converter, 5v to 3v3 power adapter (LM33) and 434meg RFM69HC's that I have.

I have wired it all up, set one as a serial gateway, and another with mock mysensors, radio's power up and show all ok, but no traffic between them tested using MYSController. Gateway module is powered from my laptop, the remote unit is powered from a 2.1V USB wall wart.

Ok, lets try changing a few things, so I swap the LM33 for LM3940 LDO regulators that I also have (And I'm powering the regulator via the VIN pin of the Nano, so bypassing the 5V and 3v3 regulators on the nano to ensure thats not part of the problem). Still no traffic.

Next step, redo the antennas (Using 1/4 length, so 173mm as advised on some sites and down to 164mm), and on playing with the Adafruit RFM69 test sketch, I find that I can get traffic between the two units if the aerials are only 4-5cm apart max. Ok, a start!

So, tried replacing the stranded wire antennas that I had with same lengths of solid copper wire (Pulled from some cat5a STP cabling), and that has now gotten me up to a range of about 2m (7 feet).

So it looks like things are travelling between the two, but the range is really bad. I have noticed with the transmitter that if I touch the antenna, then it reaches further, so should I try again with longer antennas on the transmitter unit? 1/2 wave maybe? Seems a little odd, as I would have thought that a 1/4 wave, dead straight vertical antenna would be good enough for a pretty decent range.

Would there be any improvement if I was to coil the 1/4 wave wire like you find inside consumer 433meg devices? It seems like it would make things worse than having it straight, but I'm not much of an antenna guy, so I'm not sure what to do next. Is cat5a STP cable too thin a diameter to make a reasonable antenna?

It seems like the RFM is getting enough power, or should I try a larger cap than the current 47uf thats installed on it? Have I gotten an odd version of RFM? I have an HC according to the unit, and most of the stuff I see talks about HCW or HW....

Where do I go from here? I'm aiming to be able to get these to the point where I can be confident enough to start fitting one inside a wall plate, but at present thats a long way off, I want to get the basics right first, and figure out how far I can get rangewise from these.

@vladimir , you are correct, in that you can only connect a load that is less than the rating of the relay's, or you can cause damage. Realistically what you would do is use this unit for lighting where the load required can be calculated and won't really change, or if you were using it for a switch, you would need to have some kind of labelling noting that it was only for a maxmium xxxW output.

What about using the battery packs used in cordless drills / power tools like the De Walt 18V packs or Ryobi One systems?

Find a damaged drill and cut the base off to re use the socet, or just solder direct to the terminals and use a charge module to charge it up. You can buy the batteries separately too.

They are lightweight, have a good charge storage and are pretty rugged, so put up with a bit of pounding.