Reply
Posts: 19
Registered: ‎06-13-2017

SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

Hello everybody @SiLabs,

 

since quite a while we are using simple receiver kits e.g. with Si4735 chips to push students of all ages to become interested in communications and amateur radio. I also do this in my main job - as an University professor.

As we would like extend our experiences and teaching in the future, we would like to ask (what had been asked before years ago), if there would be the possibility to receive a patch for one of those chips covering shortwave bands to enable single side band and/or reception of ASK/FSK/xPSK signals.

We would like to design simple receiver kits for training purposes, if possible completely under open source. Those cheap and simple kits should support interest in (shortwave 1,8-28 MHz, and low VHF bands 28-30, 50, 70 MHz) communications and revive a little our ham spirit with homemade equipment.

 

Well, we hope for an answer different from "sorry, that patch is available only for a specific customer"...

An alternative could be as well, if SiLabs could issue a (patched) chip variant for amateur radio use and make it available for licensed amateurs in general or through national amateur radio associations.

 

To support this aim, I can offer our participation in documention and sample hard and software design to reach our goal.

 

best regards,

 

Jürgen

 

 

Posts: 45
Registered: ‎11-04-2016

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

I made my own 3-wire serial sniffer and got this patch (sniffed from DEGEN 1103 SSB receiver), so I can share it I think, but OK, wait for Silabs answer. Why do you think Si4735 works at 28-30, 50, 70 MHz bands? I am not sure

Posts: 19
Registered: ‎06-13-2017

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

Thanks for your comment.

 

The frequency bands are just to document the bands, what we would like to get into our radio for beginners ... it's clear that the Si chips will only partially cover those bands, but, alike in other radio equipment, some additional down converter is expected to be used ...

That probably is even better, as pupils/students/adult learners can learn more about the system side of amateur radio equipment and where future developments will move forward .

Posts: 19
Registered: ‎06-13-2017

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

Well, and on a very wellknown marketplace I found out, that those DEGEN / TECSUN and other radios are so cheap, that I even could delegate such a research to students :-) ... if that would not be illegal ...

Posts: 45
Registered: ‎11-04-2016

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

Keep on ,mind -  these Chinese radios with Si4735 have very weak strength drive 

to  SDI SDIN SCK pins from MCU (it is good for  noise, but bad for sniffing), you need to solder buffers with short wires near to Si4735

Posts: 45
Registered: ‎11-04-2016

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

" if that would not be illegal" - why? This patch even not encrypted, but it is not short - about 8 kilobytes length

Posts: 19
Registered: ‎06-13-2017

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

well, that reverse engineering could fall under strict German laws about interlectual property rights and reverse engineering ... I need to let that check by lawyers, before I could use it somehow in teaching @University or even for ham radio purposes ...

Posts: 45
Registered: ‎11-04-2016

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

Ohh.. I am from Russia.. But I hope Silabs not sue us

Posts: 19
Registered: ‎06-13-2017

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

Well, depends on Russian laws about intellectual property and if they are forced by your courts ... if SiLabs would be able to track somebody ...

Posts: 45
Registered: ‎11-04-2016

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

OK, will see

Posts: 19
Registered: ‎06-13-2017

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

Hmm,

 

hello SiLabs, I am wondering, that no answer on that topic has been given, yet.

 

As my question is both aimed at academic and non-academic education to improve knowledge on general electronics and communication systems, I am indeed a little disappointed about the silence.

 

Regards,

Jürgen

 

Posts: 45
Registered: ‎11-04-2016

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

Hmm.. Silabs is my favourite company. I worked with Texas CC1350 it is just piece of **bleep**. Silabs is much, much better. Now I work with EFR32 family - very cooI.
I think in big company nobody can give answer .. Reverse engineering is not prohibited by Silabs datasheets, why you worry about?
Posts: 19
Registered: ‎06-13-2017

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

Hello,

 

I do not doubt the good quality of the chip, but when SiLabs is promising support, then they should fulfil their promise.

As we want to offer a radio kit to amateur radio interested students and adults, we need to be safe on the legal side and it does not matter, if we are selling just 5 or 1000 kits ...

 

If I want to know just for myself, then reverse engineering is not a big problem, but when I use the results, even in a non-profit environment, it IS a problem . And anyway, cooperation is much better than confrontation ...

 

BTW, I got my DEGEN 1103 today and will test it on weekend ...

 

Regards,

J.

Posts: 45
Registered: ‎11-04-2016

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

Ok, you are right. Do not forget buffers, it is important, spend 1 day looking for bug
Posts: 45
Registered: ‎11-04-2016

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

74hc244 is great choise
Posts: 2
Registered: ‎06-21-2017

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

hi Jürgen, Thanks your consider Silicon Labs product ,SI473x tuner can not support SSB or ASK/FSK/nPSK demodulation now. Maybe you get the answer "sorry, that patch is available only for a specific customer" before. Yes, we do a SSB patch on SI4735 for one customer requirement several years ago and the patch is under by contract so we can not open it .Hope you can understand it ,thanks
Posts: 45
Registered: ‎11-04-2016

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

Ok,so as far as I understand chip can do, but can not do out of box. So I think radio HAM can use sniffed FW patch, but I need license from Silabs if I want make money. Ok
Posts: 19
Registered: ‎06-13-2017

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

Hello Yake,

 

thanks for your answer. Well, I also now own a radio, what has the SI4735 chip with enabled SSB reception. I did not do any closer research now, but it looks like it is working ok ...

 

So, if would like to use your chips in some ham radio, open source, non-profit project, what would SiLabs do to support that? Would you recommend another chip and support on that SSB reception? Apart from your business contract with that customer for the Si4735, would you be able to open your chip or add an patch to support such a project?

 

As you might also know from your country and other countries in the world, we have too few young people who are interested in radio systems and ham radio. As the old, standard path from AM detector receivers to CW/SSB receivers and transmitters or FM systems (including "bugs") and later digital data transmission has become difficult due to completely commercialized industrial systems, which do not allow anything to add or change yourself, due to patents, business and commercial secrets. A lot university students nowadays can hardly use commercial radio systems correctly and according to specifications.

Therefore, we educators need systems which are open and industry supported, to properly generate the next generation of (radio) engineers. Pity, that a lot is hidden behind commercial walls in recent years.

 

Anyway, I hope there is a way and a will at SiLabs to support the ham radio and University education community with limited, but open solutions ...

 

Best regards, still hoping for something ...

Jürgen

 

Posts: 19
Registered: ‎06-13-2017

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

Hi there,

 

well, the answer could be subject to interpretation :-) ... How should we educate students to become good engineers, when all "boxes" around will stay "black boxes", what cannot be opened to analyse, improvement and learning ... in order to develop new ideas ???

 

Strange world nowadays ...

 

Regards,

J.

 

Posts: 2
Registered: ‎06-21-2017

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

Hi Jürgen Thanks your advices and I can understand your feeling.Actually SI473x chip is just design for radio tuner before. It’s not fit to use in ham radio application. But several years ago one customer require to add SSB function in their radio, so Silicon Labs with customer together do a patch based on SI4735 chip to support SSB reception. Maybe that’s what you have the radio. At the same time customer also have a contract to Silicon Labs “ can not open the patch”. Until now the agreement is still in active. On the other hand , I think if you are interested in harm radio solution , I found another brand-ATS1846 chip, maybe you can check on web for more detail information about this part for the two way radio solution.
Posts: 45
Registered: ‎11-04-2016

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

Did you mean RDA1846? It is only UHF 144.. 433 bands narrow FM. Silabs Si4735 is only one single chip SSB solution as I know.
OK, will use sniffed patch on our own risk, I hope in future Silabs will open firmware and documentation for next rf receivers generation.
Posts: 45
Registered: ‎11-04-2016

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

Another one russian with SSB on Si4735 https://youtu.be/pEiingHSjXI
Posts: 19
Registered: ‎06-13-2017

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

Hmm, well, my Russian language knowledge is practically not existing, but the pictures, sounds and actions are clear enough ... well done.

Is is not on SiLabs demo boards ?

 

Posts: 19
Registered: ‎06-13-2017

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips


yake wrote:
... It’s not fit to use in ham radio application....

well, just in the official using mode it is used in several learning and DIY radio applications, what are "officially" missing SSB reception. It is good for learning, by example to receive ham radio projects like German radio magazine transmission sunday's on 6070kHz  and for normal FM radios with RDS use. But still, much more interesting are bands from 100kHz to 30MHz, and in this area your chips are quite special without a lot of competition ...

The Russian movie shows very well, that is working and that hobbiests like ham radio enthusiasts can use it.


I found another brand-ATS1846 chip,

Well, if you mean RDA1846, what is used in VHF/UHF radios e.g. by BAOFENG , we know as well, but they do not offer necessary details to use them for anything else than FM voice, what is limiting their use for learning very much ...

Regards,

J.
Posts: 45
Registered: ‎11-04-2016

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

Look attachment

 

/*p216 AN332*/
In order to support interim updates to the device component, patches can be applied to the component by the
system controller via a download mechanism. Patches can be provided by Silicon Laboratories to customers to
address field issues, errata, or adjust device behavior. Patches are unique to a particular device firmware version
and cannot be generated by customers.
Patches can be used to replace a portion of the component (to address errata for example) or to download an
entirely new component image (to allow a customer to test a new component release on their device prior to
receiving programmed parts).
Patches are tagged with a unique identification to allow them to be tracked and are encrypted requiring the
customer to use a tag when downloading to allow the Si47xx to decrypt the patch.
Prior to downloading a partial patch, the user must confirm that the device contains the correct firmware and library
to support the patch.

 


// CMD ARG1 arg count ARG2 ARG3 ARG4.. ARG7 (if any)
const char Si4735_patch_for_SSB_reception[] = {
0x15, 0x00, 6 , 0x03, 0x74, 0x0b, 0xd4, 0x84, 0x60, /* PATCH_ARGS* Reserved command used for patch file downloads.*/
0x16, 0x6f, 6 , 0xae, 0x6c, 0xf9, 0xbb, 0x84, 0xa2, /* PATCH_DATA*/
....

Posts: 19
Registered: ‎06-13-2017

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips


DASM wrote:

Look attachment

 

/*p216 AN332*/
In order to support interim updates to the device component, patches can be applied to the component by the
system controller via a download mechanism. Patches can be provided by Silicon Laboratories to customers to
address field issues, errata, or adjust device behavior. Patches are unique to a particular device firmware version
and cannot be generated by customers.
Patches can be used to replace a portion of the component (to address errata for example) or to download an
entirely new component image (to allow a customer to test a new component release on their device prior to
receiving programmed parts).
Patches are tagged with a unique identification to allow them to be tracked and are encrypted requiring the
customer to use a tag when downloading to allow the Si47xx to decrypt the patch.
Prior to downloading a partial patch, the user must confirm that the device contains the correct firmware and library
to support the patch.

 

Thanks, it will help experimenters a lot ... I will check against mine, when I finally will open my radio as well :-) ... still to many lectures ahead and too less time for research - but our summer break comes closer :-) ...

Of course, when SiLabs finally would start to support it officially by documents and sample code, it becomes much better ... Unfortunately, a lot of companies have still not discovered the big potential of open source code and open documents to driver technical development and increase the market share of their chips ... 


Posts: 19
Registered: ‎06-13-2017

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips


yake wrote:
Hi Jürgen Thanks your advices and I can understand your feeling.Actually SI473x chip is just design for radio tuner before. It’s not fit to use in ham radio application...

Well, another proposal:

As you might now, in a lot of countries, on permanent or temporarily basis, an amateur band around 70MHz has been opened to use.
Could you probably support a Si4703 to be patched to work from 70MHz and in CW/SSB and/or narrow band FM ?
This would not be in conflict with your AM radio customer, but would open a small path for ham radio ... and you could test reliability of ham radio developers/hobbists, if you have doubts  ...

Best regards,
Jürgen


Posts: 45
Registered: ‎11-04-2016

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

Interesting.. Degen 1103 actually is not pure SSB receiver, it can receive upper and lower side simultaneously. But Tescun PL 880 can receive USB and LSB separately. And it contains Si4735, (but only for SSB demodulation, not complete receiver). Maybe Fw patch is different from 1103.. but maybe they playing with quartz filter by tuning BFO below and above filter response curve (it is double conversion superheterodyne and Si4735 acts as 2nd IF demodulator)
Posts: 19
Registered: ‎06-13-2017

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips


DASM wrote:
Interesting.. Degen 1103 actually is not pure SSB receiver ...

Well,

 

is it quite different from the first version of the DEGEN1103, I am not sure, but you most probably have read the reviews and analysis already done?

 

http://swling.com/blog/2015/11/the-new-degen-de1103-dsp-first-impressions-review/

 

http://radioaficion.com/news/andi-provides-detailed-info-and-photos-of-the-new-degen-de1103-dsp/

 

http://vcfm.ru/forum/viewtopic.php?f=9&t=130&start=1230

 

http://pup.doorblog.jp/tag/DE1103

 

https://groups.yahoo.com/neo/groups/de1103/conversations/topics

 

..and many more ...

 

 

Posts: 45
Registered: ‎11-04-2016

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

First version is simply double conversion receiver, only case and "Degen" label is same Robot Happy

 A few days ago I bought PL-660 from Tescun with USB and LSB , works fine. Not big different from DE1103 with Si4735, but Si4735 is not OK for me because AFC - I need very stable heterodyne, with syntezer. (And of course, I am going to build my own with Silabs  Si5351 as syntezer, but it is offtopic Robot Happy 

Posts: 4
Registered: ‎06-29-2017

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

SiliconLabs has an SSB/NFM patch for SI4735 family.

 

Best regards,

 

Vadim

Posts: 19
Registered: ‎06-13-2017

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips


KB1RLI wrote:

SiliconLabs has an SSB/NFM patch for SI4735 family.

 

Best regards,

 

Vadim


Thanks Vadim for this info,

 

the question is how to get it legally and with backing by SiLabs ...

 

73s de df5zx / yl3je

Jürgen

 

Posts: 4
Registered: ‎06-29-2017

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

Contact Broadcast Audio department: BroadcastAudio.Support [at] silabs.com

 

Request EVB (Evaluation Board) for 4735 and patch. You will need to sign an NDA and you will be legally ok(and backed by SiLabs) as long as you do not redistribute patch and any information provided to you under NDA.

 

Best regards,

 

Vadim

Posts: 19
Registered: ‎06-13-2017

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips


KB1RLI wrote:

Contact Broadcast Audio department: BroadcastAudio.Support [at] silabs.com



Thanks Vadim for your help. I wrote a request yesterday to the Broadcast Audio department and explaining my ideas. Let's see, when and how they are going to answer :-) ...

 

Best regards,

Jürgen

Posts: 19
Registered: ‎06-13-2017

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips


KB1RLI wrote:

Contact Broadcast Audio department: BroadcastAudio.Support [at] silabs.com



Just a short update - nothing happened, within the last 7 days I did not get any answer onto ym request of June, 30th ...

I am still hoping ....

Posts: 45
Registered: ‎11-04-2016

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

I sure no useful reply will be.. Waiting some samples from Silabs (free) and wonder, very user friendly chips, great company, TI not even close to Silabs, but..
Posts: 4
Registered: ‎06-29-2017

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

I just sent you PM with more detailed contact info.

 

73!

 

KB1RLI

Posts: 4
Registered: ‎06-29-2017

Re: SSB and/or ASK/FSK/nPSK demodulation on Si radio chips

Last message was for : df5zx