David Holland 2 Posted February 17, 2021 Share Posted February 17, 2021 Thanks for that, Gary, I did suspect as much. David Quote Link to comment Share on other sites More sharing options...
Geoff S Posted February 17, 2021 Share Posted February 17, 2021 Surely FROS must have an option to select the external module? My only experience with the Frsky OS is the few minutes it was installed in my Horus before I updated to OpenTX so I'm probably wrong. Geoff Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted February 17, 2021 Share Posted February 17, 2021 FrOS can drive the external module but it doesn't have the ability to configure the protocol used. However - if you can find the 'older'(?) multimodule which uses a rotary switch to select the protocol you could be in business. Quote Link to comment Share on other sites More sharing options...
MattyB Posted February 17, 2021 Share Posted February 17, 2021 (edited) 3 hours ago, Gary Manuel said: I doubt that very much David. It's intended for OpenTX as it relies on having the option of selecting "Multiprotocol module" in the external module format menu. That's correct - you would have to be running OpenTX or ErskyTX in order to use an MPM in the module bay. As Bob points out above, you may be able to send it a (PPM) signal, but not control which protocol and sub-protocol it uses. Edited February 17, 2021 by MattyB Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted February 17, 2021 Share Posted February 17, 2021 There's this one that can be configured without OpenTX using the rotary switch Quote Link to comment Share on other sites More sharing options...
PatMc Posted February 18, 2021 Share Posted February 18, 2021 On 17/02/2021 at 10:46, Gary Manuel said: Yes it does David. Checked on my 12s and the received signal strength and range definitely reduce. Gary, are you using a Jumper 4 in 1 module with a Horus 12s fitted with the supplied 8 cell nimh 9.6v battery without any problems ? I've just bought a Jumper 4 in 1 module but according to the instruction sheet that came with it the "working voltage" is 4.5 - 7.0v. However a search online turned up a similar instruction sheet but the "working voltage" is given as 6 - 9v. I would prefer to use the module in my Horus X12s but since that has a 9.6v Nimh battery thought it would risk over-voltage damage. I also have a Taranis X9D (original version) fitted with a 3s Life battery but I still have a good original type 6 cell 8.4v Nimh that I could revert to if necessary. Do you think I'm being over-cautious ? Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 18, 2021 Share Posted February 18, 2021 (edited) 2 hours ago, PatMc said: Gary, are you using a Jumper 4 in 1 module with a Horus 12s fitted with the supplied 8 cell nimh 9.6v battery without any problems ? I've just bought a Jumper 4 in 1 module but according to the instruction sheet that came with it the "working voltage" is 4.5 - 7.0v. However a search online turned up a similar instruction sheet but the "working voltage" is given as 6 - 9v. I would prefer to use the module in my Horus X12s but since that has a 9.6v Nimh battery thought it would risk over-voltage damage. I also have a Taranis X9D (original version) fitted with a 3s Life battery but I still have a good original type 6 cell 8.4v Nimh that I could revert to if necessary. Do you think I'm being over-cautious ? I have used it as you describe with no ill effects. I wasn't aware that there was an issue with voltages but what you say makes sense. I'll look into it before I use it again. Thanks for the warning. Edited February 18, 2021 by Gary Manuel Damned predictive text Quote Link to comment Share on other sites More sharing options...
Mike Blandford Posted February 19, 2021 Share Posted February 19, 2021 I haven't checked the components fitted to the Jumper version of the 4-in-1 module, but (from the original DIY design) the first voltage regulator is supposed to be an AMS1117-50 in a SOT223 package (5V, it is followed by a second regulator to give the 3.3V). With the current specified to be no more than 100mA, then the first regulator should be dissipating no more than around 500mW ((10V-5V) * 100mA). With a thermal resistance to ambient of 90 degC/W, this is only a temperature rise of 45 degC. With a maximum operating junction temperature of 125 degC, it should be good up to an ambient temperature (inside the module) of 80 degC. The thermal resistance may be less if there is a good copper area on the board to which the device is soldered. If they have skipped fitting this first regulator, then there will be a single regulator providing the 3.3V. This will be dropping 6.7V from 10V, so 670mW at 100mA. This will give a temperature rise of 60 degC, so OK up to an ambient temperature (inside the module) of 65 degC. If they have fitted different components or used smaller packages then these would need to be checked. Mike 1 Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 19, 2021 Share Posted February 19, 2021 Thanks for the speedy PM response Mike. I was toying with the idea of adding an in-line 5v regulator, but maybe I don't need to. I'll have a look inside the module (if I can open it) to see if I can make out whether 1 or 2 regulators are fitted. Specs I've seen suggest that some are rated at 7v max but others are 9v max. Maybe this reflects whether they are single stage or 2 stage? On the basis that mine hasn't blown up being supplied at 9.6v, I suspect that it will be a 2 stage one, but I'll check. Thanks again for the info. If I discover anything I'll report back here. Quote Link to comment Share on other sites More sharing options...
EarlyBird Posted February 19, 2021 Share Posted February 19, 2021 I have just checked my spec sheet and it is 7v max. The module connects to the Tx and the Tx regulates the battery, surely. I am therefore thinking that the voltage at the module connector is not the battery voltage but a lower regulated voltage. Anyone fancy testing this theory with a volt meter? Just a thought.... Quote Link to comment Share on other sites More sharing options...
Mike Blandford Posted February 19, 2021 Share Posted February 19, 2021 28 minutes ago, EarlyBird said: I have just checked my spec sheet and it is 7v max..... Really? 6 NiMh or 2 LiPo/Lion will be over 7V so that module isn't specified to work in many transmitters! The Taranis switches battery voltage to the external module connector. Mike Quote Link to comment Share on other sites More sharing options...
EarlyBird Posted February 19, 2021 Share Posted February 19, 2021 (edited) Now that's got me worried. Looking at the jumper web site Multi-protocol Module | jumper-rc (jumper-rc.com) 6-9v looks better and more plausible as the module is designed to fit the Taranis which has a max 8.4v IIRC. Who to believe? Not to worry I will just keep using it. Just looked at the data sheet that came with the module and the picture shows the module with the dial on the back. Mine does not have the dial, wrong data sheet? The above specification is for the module I have, again looking at the pictures on the web site. Now I am happy to keep using it. ? Edited February 19, 2021 by EarlyBird More info added Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 19, 2021 Share Posted February 19, 2021 (edited) Right. I've got a bit of info from opening mine up. It was getting dark so I was a bit limited and couldn't take photos, but here's what I've found. 1. It is fitted with 2 regulators. The first one is a AMS1117-50 (might be 5.0) and the second one is a AMS1117-33 (might be 3.3). Either way, that makes them 5.0v and 3.3v regulators. Both are SOT-223 packages. Datasheet here: https://www.digchip.com/datasheets/parts/datasheet/015/AMS1117.php 2. There is a jumper which looks to be associated with the regulators. The jumper has a shorting link fitted between the centre pin and one of the end pins marked as S2. The other end pin is marked S1. If I was a betting man, I'd put money on the S2 position using BOTH regulators to give an input voltage range of 6 to 9 volts and if moved to the S1 position using just the 3.3v regulator, giving an input voltage range of 4.5-7.0 volts. Pure guesswork on my part, but I have a feeling that that is what it's for. 3. The board is a Multiprotocol v1.3 and it is marked as "(CC)-BY-NC-SA", which means that it is free to be shared and adapted for non commercial applications provided that attribution is given to the original licensee. There may therefore be a schematic diagram somewhere but I haven't managed to find it yet. From my limited knowledge of voltage regulators and from the datasheet, both regulators are rated up to 12 volts (absolute max 15v) input. There does not appear to be any specific reason for a maximum voltage of 9v (or 7.0) other than heat dissipation. Whether this means that it's ok to carry on using with 8xNiMh at up to 10.4 volts (8x1.3), I'm not sure. Oh and one other thing I noticed. The circuit board is made to accommodate the dial and bind button for PPM compatible versions, but the positions are not populated in the serial only version like mine. Edited February 19, 2021 by Gary Manuel Added info about dial. Quote Link to comment Share on other sites More sharing options...
EarlyBird Posted February 19, 2021 Share Posted February 19, 2021 Gary, That all makes sense and ties up nicely with the data sheet supplied with the module (with dial) and the one on the website (without dial) which we have and rated at 9v. We are good to go then? ? Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 19, 2021 Share Posted February 19, 2021 (edited) I've found a couple of schematic diagrams but not for the version 1.3 that I have. All versions show an input voltage of 12v, so presumably that's what it's designed for. The schematic at the bottom of the page shows the jumper link, which effectively shorts out the 3.3v regulator, meaning that I've lost my earlier bet. https://github.com/pascallanger/DIY-Multiprotocol-TX-Module/blob/master/docs/BOM_DIY_STM32 %26 Schematic.md Edited February 19, 2021 by Gary Manuel Link added - oops. Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 19, 2021 Share Posted February 19, 2021 (edited) 22 minutes ago, EarlyBird said: Gary, That all makes sense and ties up nicely with the data sheet supplied with the module (with dial) and the one on the website (without dial) which we have and rated at 9v. We are good to go then? ? You are definitely good to go with a taranis at 8.4v max (if that's correct). I'm not as confident with Horus at 10.4v, but I'm a bit more confident now I've seen the specs, schematics and technical info from @Mike Blandford Edited February 19, 2021 by Gary Manuel 1 Quote Link to comment Share on other sites More sharing options...
EarlyBird Posted February 19, 2021 Share Posted February 19, 2021 Taranis is what I have thanks ? Quote Link to comment Share on other sites More sharing options...
Mike Blandford Posted February 19, 2021 Share Posted February 19, 2021 Schematics for boards up to V1.1 (in EAGLE format) are on the Github pages (go back up to DIY-Multiprotocol-TX-Module then follow STM PCB). I think you will find that link is for putting the CPU into internal bootloader mode. Looking at the board layout for V1.1, there is a reasonable amount of copper acting as a heatsink, so the thermal resistance should be better than 90 degC/W. Even from 12V, you are looking at a maximum of 700mW power dissipation from the 5V regulator. So 63 degC junction to ambient at 90 degC/W so OK to an ambient temperature of 62 degC and should be somewhat less. This is assuming a current drain of 100mA (max. specified). Mike Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 19, 2021 Share Posted February 19, 2021 Thanks Mike. 62 degrees ambient should be warm enough to be felt by touching the module casing. I've never noticed it getting warm but it's something I'll be looking (feeling) out for in future. Quote Link to comment Share on other sites More sharing options...
PatMc Posted February 20, 2021 Share Posted February 20, 2021 Thanks Gary, Mike & Steve for the inputs since my query re the safe max voltage input to the 4 in 1. It seems that Steve has the same (older version?) instruction sheet as me that quotes 7v max. The photos of the module on the sheet I got are such poor quality that, without using a magnifier, it's not obvious it's a different version from the one supplied. Steve, I have the earliest version Taranis which specs the "op voltage range 6 - 15v (2s, 3s lipos are acceptable)". Given the info now unearthed I've decided to use my Taranis with the 3s Life battery installed but I will monitor the warmth of the module for a while. I've still got to install the FW so might soon be back with more questions. Quote Link to comment Share on other sites More sharing options...
PatMc Posted March 16, 2021 Share Posted March 16, 2021 (edited) Help please. I've finally got around to the point of installing the FW in the 4 in 1 module but hit a snag. It's stressed that the channel order should (must ?) be the same as that of the donor Tx. Unfortunately my Taranis uses AERT which isn't one of the options available. Changing this order would need a lot of changes in mixes etc of the existing models with a significant risk of missing the odd one or two. I'm thinking of using AETR channel order in the module then checking & correcting any subsequent wrong re-mapping in the Taranis. Can anyone verify that this will be OK, please ? Edited March 16, 2021 by PatMc Quote Link to comment Share on other sites More sharing options...
EarlyBird Posted March 16, 2021 Share Posted March 16, 2021 AERT is an option. On my Taranis with the 4in1 model selected. I am normally in AETR to get AERT I have to scroll backwards. Quote Link to comment Share on other sites More sharing options...
PatMc Posted March 16, 2021 Share Posted March 16, 2021 Am I doing something wrong ? This is a screen grab of the only options I seem able to get. Quote Link to comment Share on other sites More sharing options...
Geoff S Posted March 16, 2021 Share Posted March 16, 2021 (edited) My module is in my Horus X10 and both AETR (which is my usual choice) and AERT are options in the Sys menu Edit: Sorry Pat, I think I misunderstood you. It's so long since I updated the firmware I'd forgotten the choice I made and the options available. Edited March 16, 2021 by Geoff S Quote Link to comment Share on other sites More sharing options...
Dickw Posted March 16, 2021 Share Posted March 16, 2021 PatMc I may be talking rubbish, so please ignore if it is not relevant. I use am 4 in 1 MPM in a "non-Open Tx" application so had to edit the firmware in an Arduino editor. Just looking at that, I see that AERT is an option. If it is not available to you perhaps using the Ardiuno editor is an option. Just for the record I use ETAR and it works fine after my edit. Dick Quote Link to comment Share on other sites More sharing options...
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