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Due EOL of RFM12B, current emonTX V3 and emonTX V2 shield production are still using RFM12B, or is already switched to RFM69CW ?

Thanks

As long as you can buy stuff without the radios and the software still support changing frequency, I don't see a problem

Yes, I know I can buy stuff without radios.

But because HopeRF do not produce anymore RFM12B, but produce only RFM69CW, RFM69HCW etc, and because I've read that new version of EmonTX (v. 3.4) is going in production, what I would like to know is:

the next batch of EmonTX v.3.4 with RF 433 Mhz, will produced with RFM69CW at 433 Mhz, or with RFM12B ??

In the case of RFM12B I assume by using the last ones remaining around, at least until there is some stock.

@sovking Speaking to our contacts at HopeRF there are no plans to stop producing RFM12B, however they have discontinued support. The next revision of the emonTx V3 (V3.4) has been designed to work with RFM69CW however due to urgency of getting first manufacturing run of emonTx V3.4 underway this week and lack of availability of RFM69CW we have had to use RFM12B on the first batch of 500 units of emonTx V3.4. They next production run in the new year will have RFM69CW. The JeeLib driver allows for backward compatibility.

We also have a revision of the emonTH and RFM12Pi / RFM69Pi in the works due to get into production early next year, these will have RFM69CW

@haden yes, we will always make available no RF versions of the units 

We will continue to sell RFM12B 433/868 as loose items in the shop 

Hi

Just looked at the shop. I don't see any way to get e.g. the RFMxxPi without the radio. There is a complete option with the radio or the PCB only. Will it be possible to buy it without the radio, but with everything else?

@sovking,

"HopeRF do not produce anymore RFM12B"

More accurately, Hope RF do not sell small quantities of RFM12B anymore (current minimum order now 1,000 !) - this means it is vanishing from the shelves of small volume distributors.

The 433 MHz and 868 MHz variants are most definitely in production.

Sorry to re-activate an old thread but I am just about to start my adventure with OEM and I am confused as to whether to go with 868MHz or 433MHz and so I decided to look up what others say on the forum and discovered this thread... and now I am even more confused (doesn't take much tbh!!!!).

I know it this thread is 2014 but the suggestion here is that OEM will standardise on 433MHz and yet, today, you can choose between 433MHz and 868MHz.

I assume that the concept of standardisation no longer applies?

I have a weather station that uses 868MHZ I am assuming it would make more sense for me to get a 868MHz Open Energy Monitor system so I could then more easily incorporate the weather data into the Home Monitoring System (?).

The decision was made to standardise on the 433 frequency to reduce the lines stocked in the shop and ease installation etc. but it does seem various 868MHz items are appearing in the shop but there has been no counter announcement about stock lines. however I do believe the 433 standard is generally followed, I would certainly assume any discussion to be about 433 unless indicated otherwise.

If you have a 868MHz weather station, I would think you are better off with a 433 OEM network as the 2 will not be directly compatible so you will need 2 x 868 networks and that could mean interference etc.You could probably still integrate the weather station with your OEM set up but the RF protocols and data parsing will differ.

If you are thinking of using a Pi you can use a RFM2Pi and a JeeLink to get 2 networks up and running.

Paul

I think the correct description of the situation is 433 MHz was more popular, by a large margin, therefore it makes sense to stock 433 MHz and offer this as the preferred choice. Quickly looking through the Shop, only the emonTx Shield and the GLCD are offered as either 433 or 868 MHz, there's no choice for the emonPi nor the emonTx V3.4.

"only the emonTx Shield and the GLCD" plus the RFM69Pi and the emonTH :-)

Both of which have been put into production since the proposed standardisation, which would suggest the shops decision regards stocking less lines was not set in concrete. There is a natural and preferred lean to 433 but 868 devices are still stocked. therefore still easy to get and use but there has been no "official" change in the position to pursue 433 standardisation as far as I'm aware.

Paul

We are *trying* to standardize on 433mhz, however we understand that many users have 868mhz networks there we are still offering a few 868mhz unit to help these customers. If you setting up a new system I would recomend going for 433Mhz. 

Thanks for all your replies.

I have decided to stick with 433 then as this is a brand new network and I can always access any 868 devices I have through a standalone Arduino with a 868 RMF69CW if I wish.

Thanks for this, but are possible interference from EmonTx and my home alarm that work at 433? 

Yes, interference is possible. If you are concerned, email the shop and ask about the availability of 868 MHz versions of the items you require. But first, check that 868 MHz is legal where you are.

I have an emonBase, emonTX Shield and a DIY emonTH all up and running now on 433MHz but I have found that a lot of packets go missing leading to extended update periods. Using minicom I see that I have a very busy 433MHz environment and I suspect that packet clashes are causing data to get dropped.

So I have decided to switch to 868MHz before I get any more nodes. I originally ordered 868MHz but changed my mind hoping that the 433MHz band was clear enough but I have a Davies Weather Station, wireless solar PV inverter, Heatmiser CH tehermostat, and quite a few other devices on the 433 band. The 868 band should be a lot clearer.

Of course, 868 is not legal in some places but it is OK here in the UK :-)

I've a emonTH (RFM12B at 868mhz) that I'd like to use with an EmonPi at 433mhz. Noting Glynn says I can "force the modules in software to work on a different frequency" is it simply a case of changing the frequency in the sketch? I'm assuming I'd need to swap the antenna for a 165mm? Reduced range is fine as only a few meters away, but anything else I should know? Thanks :-)

I'm using the 'wrong' frequency all the time when checking sketches, and yes, it is 'just' in software. I don't change the antenna, so I can't confirm the effect of that, but doubling the length should at least tune the antenna correctly, which should improve the radiated power.

But a caveat: the RFM69CW data sheet warns that you must not operate the module at full power without an antenna, else damage might occur, (but if memory serves, it doesn't specify a safe maximum power) so I would suggest that at the wrong frequency, the same could apply. I'm not aware of the same restriction with the lower-powered RFM12B.

Yes, the RF chip is identical, hence only 'software' to change frequency band. However, the module has the antenna filtering/matching L's & C's that are band dependent - the considerable mismatch of operating in the 'wrong' band is why both the transmitted signal and received strength are so much lower.  

Luckily for bench testing and short range, the units still function fine (saved by log scales !).

Now Robert makes a good point - you are pumping the same power into the transmit circuit, but only a fraction now makes it out to the antenna - where does the rest go?  Well, mostly it is reflected back from the mismatch and warms up the transmit section.  Provided you have a reasonably low duty cycle, this has not been a problem in practice - I certainly would not operate at full power/100% duty cycle though !

I have noticed that there are a dwindling number of products available in the shop to work at 868. At the moment the Raspberry Pi RF Add-on is available at 868 and EmonTH is available as a No RF version. Are these going to be phased out as well?

We can still supply 868mhz versions if you leave a comment with you order at checkout. 

Given there is no real cost to you guys in leaving the 868MHz versions as line items in the store, I'm not sure why you wouldn't do that. Or if you don't or can't do that for some reason, wouldn't it be a good idea to change the descriptions of the relevant items to say they can be delivered as 868MHz if requested through the comment field on the order.

I can't be alone in having several 868MHz devices around. I was a bit miffed the other day when checking something out in the shop to see that only 433MHz was supported now, so my immediate thought was. 'Brilliant, now if I need to expand my system I'm going to have to replace everything and swap to 433MHz!' 

Surely the shop should be supporting those of us who are already committed to 868MHz by continuing to stock devices on this frequency. Or at the very least making sure we know we can ask for that option.

Thanks, that is excellent. The reason I got involved in wireless control and monitoring was because of problems faced by a client with a boiler control system on 433, that would fail to operate because of the high level of background interference in that band. I would like to stick with 868,