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Anyone see this yet? RS-918SSB $350

Does the mcHF also have FreeDV (HF digital voice) included as this unit apparently does ?

That amazon ad is for $450 not $350 as quoted earlier, so it’s probably worth waiting a while to see where the final street price lies.


What is the Chinese manufacturer giving back to the community? That’s what I would want to know before I spend with them.

The design in open hardware and open source so anyone can take the designs and make them. But I would rather spend my money with a company that feeds some of the profits back into funding the designers than one that just takes and makes.


No argument from me. But it did make me aware of the M0NKA project going on, and would look at buying from them to support the community.

If indeed this is a clone of M0nka’s mcHF design - this manufacturer would appear to be in conflict with what is stated on the m0nka site namely:

This site is the home of the mcHF QRP transceiver. It is a small, home-brewed amateur radio project. Firmware is released as open source and most project files are released as well, with the only restriction of not commercial use (manufacturing and sales of kits or complete product).

I’d say this is a clear DON’T BUY the RS-918SSB indicaton!

I looked at it on Amazon after reading the posts so far. Don’t think I would buy it; first the Amazon seller is a brand new unrated seller, secondly is the concern about quality and what they may have done to otherwise good firmware. Thinking of the Xiegu HF radio as an example, not being supported and US distributor is dropping them due to user problems with no factory support. Sometimes it dosen’t pay to be an early adopter.

Looks shiny and small. Some may think it could compete with a KX3 for power. Never knew about the MONKA project. Time to go and check it out.

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This is an interesting thread, relevant to this one:

Makes me sick that they rip off other homebrewers projects for profit.

Definitely don’t buy it, build the original and have all the satisfaction of making it yourself.

What is wrong with the world…

I am finding assembling a rig with surface mount components a mountain too high to climb. So maybe I would pay someone to do the assembly for me. It’s an ill wind etc.


Ron, there’s a version with the surface mount components populated: http://www.m0nka.co.uk/?page_id=740


Not only have the Chinese put ALL the parts on the board, they have put it in a nice box, with readout, knobs etc and tested it. Sure REAL amateurs would roll their own. I know two of these rare people.

I don’t think there is any law prohibiting the use of open software being used in a box that is sold. Icom sell rigs with D-star which is supposedly open source.

Yes I know about the “commons” agreements but that’s really only a voluntary code. Try prosecuting someone in China or America for making a quid from offering a complete working box using open software. There are android type computer operating systems using open source material that you have to pay for. And so on.

Ideally the Chinese would have made some sort of arrangement with the designer which would return a few dollars to him for his effort. But if he really wanted to make money he would not have offered the code for free. More power to his pencil but good ideas are always going to be used by someone to make a quid.

PS, I haven’t put an order in for the not yet in production model.

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Still waiting for an answer to this please - from those of you with the M0NKA mcHF rig, thanks.


Apparently it does. There’s a Yahoo group for the mcHF that references this occasionally, and there’s this video of DL1CR using it with FreeDV https://youtu.be/x-J1kLszeQQ . It looks like a dandy project at about half the cost of a KX2, I’ve had my eye on it for a while. Unfortunately it only puts out 5W ‘stock,’ but I’m sure there are ways to boost the power. Here’s the technical specs from the project wiki: https://github.com/df8oe/mchf-github/wiki/Technical-Specifications

Thanks John,
That’s good news that the Open Source FreeDV digital voice is possible with this design. I’ve been testing FreeDV since the early days but having to have a PC attached to operate it, rather than the code being built into the rig has always been a problem (especially when considering portable operation). I presume the latest Flex systems with PC built in will continue to support FreeDV but they are in a different price class of course.

73 Ed.

I think if the M0NKA group had a kit with the box and all, that would be a great help. Still like the kit idea with the surface mount items already done.


The software is Creative Commons the hardware is not, and never has been. These Chinese are a bunch of pirates that have ripped off Chris’s hardware design and he has not received a penny from them.

The rig is able to put out 10 watts with ease (careful winding of the output transformer is needed to do that), there is no way I would push the output devices much higher than 10 watts if only to remain friendly with any nearby amateurs!! Best rig to use on a cold day, the heat from the regulators definitely keep your hands warm!

Barry GM4TOE

It wouldn’t be worth it. But its morally wrong that is the point…


“And watching…for pigs on the wing”.

I had to check and it’s 40 and 1/2 years old. I remember its release.


The requirements of a Free or open source license typically (depending on the license) require that the software is made available once distribution occurs. There is no requirement that the software be made “free” as in beer; there are many companies that have made a lot of money commercialising aspects of Free and Open Source Software.

Most license conditions trigger on the “distribution” event, implying you can make your own modifications to software for personal use, but the moment you give them to someone else, you have to also provide source code for those modifications (or for the entire derived product, depending on license).

Creative Commons is another form of use of Copyright licensing to allow greater control over distribution rights. It comes in a bunch of forms, including BY (attribution), NC (non-commercial), ND (no derivatives), and SA (share-alike). These can be combined to make a license like CC-BY-NC-SA, which would require any person who made a derivative work to attribute the original source as me, have no commercial gain, and share their derivative work under the same license.

This doesn’t preclude the original copyright owner from reaching a licensing agreement with a distributor to make commercial products under a different license, but the product released to the world under CC and modified by a non-copyright holder would have to stay under those terms if licensed SA.

Actually, there are quite a few prosecutions for people who violate the licenses - they don’t get reported often, and less so now Groklaw is no longer online. In America, the Software Freedom Law Conservancy and EFF have been known to target vendors that don’t meet their obligations under terms of various F/OSS licenses. There have been similar cases in Europe. In almost all instances, the vendor doing the license violation loses or settles pretty damn quickly.

In China, the government is cracking down more and more on shonky operators as they lose manufacturing contracts due to IP protection. As wages grow in China, there needs to be a stronger incentive for producers to use Chinese manufacturers, rather than shipping everything off to Vietnam or Indonesia. The problem there is it is so systemic these actions don’t appear to be having much impact from the outside. There has been some anecdotal success of targeting the OEM that is producing infringing product, rather than the distributors. OEMs that permit IP violations don’t last long once that fact gets out.

What is missed sometimes (not the case in this instance, but worth reiterating) is that if the person is that releasing hardware under something like the Open Hardware License basically means you are allowing someone to rip your design off. You’ve made that choice. If you release software under the GPL, you are basically saying you expect others to take that software and develop it further, even selling it if they so desire. Your protection under the license is they have to give their modifications back too, which allows you to sell it too.

(IANAL, I just work for a company making a lot of money off Open Source software)

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I actually have one of these clones, RS-918, and I must say that after some slight modifications it´s a really good QRP rig. However, I had to change the MCU since the original was 168 MHz, 192 kB ram and 512 kB flash. I changed to STM32F429VIT6 which is 180 MHz, 256 kB ram and 2048 kB flash. It sure made all the difference. Also I did a modification of the stock crappy microphone, replaced the element with a real electret and drilled three small holes on the backside to allow better dynamics. The last thing I did, and this is also a problem with mcHF, was to machine a new heatsink which has the benefit of more effective heat dissipation.

I did this since I´m a tinkerer and enjoy experimenting, but one should not simply embark on the route to change MCU without proper tools and knowledge, It´s a 14.2x14.2 mm SMD chip with 100 legs.