Re: [Freetel-codec2] FYI: mode 2400B handheld

[David Rowe]

Fine business Jeroen,

Great set up and experiment!

I've been experimenting with direct FM modulation of my FT817 using the 
"data port" connector on the back. This works well, and I can pick up 
the 2400A signal on a SDR OK.  I'm using an external DAC (actually a 
stm32f4 discovery) with response down to DC (not a sound card) to 
modulate the FT817.


There's a cmd line utility (fsk_mod_ext_vco.c) I wrote to support the tx 
side.  By using an external SDR for Rx we can (hopefully) get a 10dB 
lower MDS than FM or otehr DV systems.


Cheers,

David

On 02/05/18 07:30, Jeroen Vreeken wrote:

Hi all,

A small update: the dra818 module is a bit dissapointing. The worst 
problem: it takes almost a second before it modulates after switching to TX.

So I went for a different approach:

A while back I modified my FT817 a bit to make the 455kHz IF available 
on the back. This is done by using the connections available for the 
optional filter. This filter is used both for receiving and for 
transmitting.

http://dmlinking.net/ft817_24khz/IMG_20161219_212016small.jpg
For receiving I use a 455kHz filter and a simple one transistor 
amplifier and feed the result directly to the atsame70.

The CPU samples as 96kHz resulting in a 25kHz digital IF due to aliasing.

Transmission is done similarly by outputting a signal at 25kHz on de DAC 
and mixing it (with a 4053) with a 480kHz square wave signal generated 
by a timer on the CPU. After filtering it with a 455kHz filter it is fed 
back to the FT817.

A seconds switch of the 4053 is used to switch between the rx and tx path.

http://dmlinking.net/ft817_24khz/455kHz_trx_small.jpg

Right now the following works:
-FM demodulation of voice (filtered and with deemphasis)
-pure FM demodulation (also capable of receiving DC)
-FM modulator (both voice and sine test signals)
-FreeDV 2400A transmission (not sure if it works due to lack of a 2400a 
capable receiver)

-FreeDV 2400B transmission

The local repeater PI2EHV successfully received the 2400B signal and 
decoded it just fine.

Recording of the received audio at the repeater can be found here:
http://dmlinking.net/audio/2018/05/pi2ehv.ampr.org.201805012000.wav
(The signal was fine, the audio going into the encoder was terrible, 
just a simple electret mic connected to the atsame70 cpu)


The first results are encouraging and it looks like this is an easy way 
to get on air with the 2400 modes on any band the FT817 supports. But 
there is still a lot of debugging to do. For some reason encoding 2400B 
stops after about a minute of transmitting...


73,
Jeroen PE1RXQ

On 01/09/2018 03:32 PM, Jeroen Vreeken wrote:

Hi,

For a while now our local repeater PI2EHV has been capable of 
receiving both analog FM and FreeDV mode 2400B.

However the amount of digital users is low (not a big surprise).

Inspired by the SM1000 I have been thinking about a project to make 
using it easier: A small handheld capable of mode 2400B.
Nothing really fancy, but it should be able to show of some features 
(like FPRS position reports interleaved in an audio stream) while 
making communication in the field as simple as possible. And of course 
it should be an open design. Since the inspiration came from the 
SM1000 I would like to call it the 'HT1000'.

The basic design would consist of:

    - DRA818 FM transceiver module
    - Small GPS receiver
    - LiPo battery
    - Atmel ATSAME70 cpu
    - Speaker & mic
    - Display and controls
    - Glue circuitry to let it work together
    - 3D printed housing

As of last night the first step is working: an ATSAME70 running 
freedv_rx() and freedv_tx() between two AD converters and two DA 
converters. Next step will be connect a DRA818 module so I can 
actually test on air.


73,
Jeroen PE1RXQ



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Re: [Freetel-codec2] FYI: mode 2400B handheld

[Curt, WE7U]

On Wed, 2 May 2018, Jeroen Vreeken wrote:


A small update: the dra818 module is a bit dissapointing. The worst
problem: it takes almost a second before it modulates after switching to TX.
So I went for a different approach:


You might reconsider as I've been playing with one module that works much 
better.

A buddy reported several years back that he had found a German ham forum 
discussing the 1W Chinese modules: The Dorji DRA-818, the NiceRF SA-818, and 
later the Sunrise Electronics SR_FRS_1WV. I noted it at the time but didn't 
read the forum myself until a few years later, after I had bought some of the 
NiceRF modules.

The forum is here:  http://www.qrpforum.de/index.php?page=Thread=9797

I don't read German so used Google Translate to glean what I could out of it. 
Based on what I learned I bought some Sunrise Electronics modules in 1W and 4W 
versions. My purpose is packet at the moment rather than Codec2, but you might 
investigate to see if that module suits your purpose better than the DRA-818. 
They also have 0.5W VHF modules and UHF modules from 0.5W to 2W.

As an aside, if anyone wants some NiceRF 1W modules to play with I'd part with 
the qty 5 each VHF and UHF modules I have.

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APRS in Search and Rescue:  http://we7u.wetnet.net/search_and_rescue.html
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Re: [Freetel-codec2] FYI: mode 2400B handheld

[glen english]

probably not HARD amplitude limited. sign bit would still rule though...

but band limited of course. and if in linear mode, AGCed so there would 
be a reasonably consistent level there, FM or SSB probably 10-16dB max 
dynamic range. (guess)


still worthwhile doign your numbers to see where all the sampling 
products land, and also, where the aliases of the harmonics present on 
the fitler output (non zero) and 2f of the created ADC distortion land. 
the 2f and 3f can get very bad with under specified sample AND holds  
when operating super nyquist.





On 2/05/2018 9:51 AM, David Rowe wrote:
I like it. good use of undersampling. Although the SFDR of the 
microcontroller at 4x undersampling is probably in the toilet, since 
it is band limited, that does not matter of course. very good.


Glen - would the FM be limited by that stage?  That would mean a 
simple ADC would suffice, we're just looking for the sign bit.


- David

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Re: [Freetel-codec2] FYI: mode 2400B handheld

[David Rowe]

I like it. good use of undersampling. Although the SFDR of the 
microcontroller at 4x undersampling is probably in the toilet, since it 
is band limited, that does not matter of course. very good.


Glen - would the FM be limited by that stage?  That would mean a simple 
ADC would suffice, we're just looking for the sign bit.


- David

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Re: [Freetel-codec2] FYI: mode 2400B handheld

[glen english]

Great work Jereon !

I like it. good use of undersampling. Although the SFDR of the 
microcontroller at 4x undersampling is probably in the toilet, since it 
is band limited, that does not matter of course. very good.


glen VK1XX


On 2/05/2018 8:00 AM, Jeroen Vreeken wrote:

Hi all,

A small update: the dra818 module is a bit dissapointing. The worst 
problem: it takes almost a second before it modulates after switching 
to TX.

So I went for a different approach:

A while back I modified my FT817 a bit to make the 455kHz IF available 
on the back. This is done by using the c




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Re: [Freetel-codec2] FYI: mode 2400B handheld

[Matei Alexandru Coltoiu]

I would rather add bluetooth support for it. You could then couple it to a
smartphone and have all apps.  You could even use a headset.

On 10 Jan 2018 14:04, "Adrian Musceac"  wrote:

> Hi Jeroen,
>
> This is a very interesting project. If there's anything I would
> change, I would add a more powerful CPU, capable of running some other
> applications, like chat, maps, email, pictures.
> Otherwise you could end up for example receiving a position report but
> no being able to plot it without an external computer. Have you
> considered using an SBC instead?
> Myself I am approaching this differently. I am pushing for a SDR
> solution but I lack the skills to design a good frontend with small
> dimensions. Components for ISM bands are plenty and cheap, not so for
> ham bands.
>
> Regards,
> Adrian
>
> On 1/9/18, Jeroen Vreeken  wrote:
> >
> > Inspired by the SM1000 I have been thinking about a project to make
> > using it easier: A small handheld capable of mode 2400B.
> > Nothing really fancy, but it should be able to show of some features
> > (like FPRS position reports interleaved in an audio stream) while making
> > communication in the field as simple as possible. And of course it
> > should be an open design. Since the inspiration came from the SM1000 I
> > would like to call it the 'HT1000'.
> > The basic design would consist of:
> >
> >  - DRA818 FM transceiver module
> >  - Small GPS receiver
> >  - LiPo battery
> >  - Atmel ATSAME70 cpu
> >  - Speaker & mic
> >  - Display and controls
> >  - Glue circuitry to let it work together
> >  - 3D printed housing
> >
>
> 
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Re: [Freetel-codec2] FYI: mode 2400B handheld

[Adrian Musceac]

On 1/10/18, Sebastien F4GRX  wrote:
>
> -during your own developments, avoid reinventing the wheel. Focus on
> existing
> open standards when one exists. For example, use IP, TCP, and things like
> that.
> We have a full class-A 44/8 IP network reserved for our own ham use. That's
> 16
> million addresses. If we starve, we will find a solution later. If some
> people
> tell you that IP addresses need to be coordinated, then okay, later. Let me
> play
> before we need to coordinate. Only invent something when current open
> standards
> dont exist or cannot be used. Open standards are good for many reasons: to
> save
> time, to ensure interoperability, etc.
>

I agree completely. There's DMR out there, and it's taking off here
like wildfire. Tetra is better, but there's no open source basestation
code and the standard is quite complex and handsets are hard to get at
least until state agencies switch to LTE. There's also P25 and I think
OP25 is the project to watch in the future. OP25 basically now has a
full layer 1 and layer 2 implementation. It's mature and has support
from a known entity. But it has no layer 3 behind, so that's a place
to start digging.

Regards,
Adrian

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Re: [Freetel-codec2] FYI: mode 2400B handheld

[Adrian Musceac]

On 1/10/18, Sebastien F4GRX  wrote:
> Hello,
>
> Yes we need to get more people interested in open DV systems.
>

Lack of interest is a BIG problem. I have my own project which I
mentioned here before. It's basically a PoC, a toy, without much use
outside of making "cool" demos or introducing SDR to school students.
But with some effort it could serve as a layer 1-2 for a bigger
system. I've been looking for a layer3 solution for a long time,
something that would fit the amateur radio scope.
No luck yet. The landscape is too fractured and too few people
actually working on stuff.
The reality is that you need very solid infrastructure to make a dent.
And that infrastructure is very hard to do properly. The project I
consider the most advanced is SVXlink. We have a nation wide network
based on it. But it's time to phase out pure analog systems and Codec2
has the chops to do it.

Regards,
Adrian

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Re: [Freetel-codec2] FYI: mode 2400B handheld

[Sebastien F4GRX]

Hello,

Yes we need to get more people interested in open DV systems.

My part of the job at the moment is building an UHF modem that also talks
ethernet, so we can connect it to hamnet.

It will be a kind of accesspoint for mobile units, OR, a gateway to build long
range hamnet UHF links.

One of the goals is to provide an alternative to wifi for hamnet links.

I believe that having working boards can motivate more people to develop
applications.


Sebastien


Le 10/01/2018 à 17:10, Adrian Musceac a écrit :
> On 1/10/18, Jeroen Vreeken  wrote:
>> http://dmlinking.net
>>
> That's a very well architected project, and I'm not saying it lightly.
> Unfortunately the user docs are quite sparse, and it does not have
> enough visibility.
> Basically I would have liked to know if I could use that to have:
> - analog compatibility (fallback to analog FM streaming)
> - be able to link multiple repeaters or DMO stations just like svxlink
> does, without having to transcode from one codec to another
> - all the features of svxlink: parrot, announcements, offline
> messages, RTL-SDR support via external PHY interface
> - be able to interconnect with other networks like Echolink (I
> recognize that this might require transcoding)
> - be able to roam seamlessly between repeaters
> - be able to have support for multiple talkgroups on a single
> repeater, the way DMR works
>
> Hopefully more people will get interested in this kind of projects in
> the future.
>
> Regards,
> Adrian
>
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Re: [Freetel-codec2] FYI: mode 2400B handheld

[Adrian Musceac]

On 1/10/18, Jeroen Vreeken  wrote:
> http://dmlinking.net
>

That's a very well architected project, and I'm not saying it lightly.
Unfortunately the user docs are quite sparse, and it does not have
enough visibility.
Basically I would have liked to know if I could use that to have:
- analog compatibility (fallback to analog FM streaming)
- be able to link multiple repeaters or DMO stations just like svxlink
does, without having to transcode from one codec to another
- all the features of svxlink: parrot, announcements, offline
messages, RTL-SDR support via external PHY interface
- be able to interconnect with other networks like Echolink (I
recognize that this might require transcoding)
- be able to roam seamlessly between repeaters
- be able to have support for multiple talkgroups on a single
repeater, the way DMR works

Hopefully more people will get interested in this kind of projects in
the future.

Regards,
Adrian

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Re: [Freetel-codec2] FYI: mode 2400B handheld

[Adrian Musceac]

There was a project based on a CML Micro chip (the same one used in
Tetra handsets), I think Bruce Perens was its godfather. It sounded
very interesting considering those chips were not very expensive, but
I have no idea what the status of that is currently.

My main concern is coming up with a good frontend. I think that's very
hard and basically out of reach for an amateur project.

On the other hand, may I suggest taking a look at LMS7002 by Lime
Micro, it's a full featured chip designed for cell networks and it's
very well documented. The company behind it is very user-friendly and
they actually go out of their way to provide support for amateur
radio.

Regards,
Adrian

On 1/10/18, Sebastien F4GRX  wrote:
> Let's build a module with these:
>
> http://www.analog.com/en/products/rf-microwave/iq-modulators-demodulators/iq-modulators/adrf6755.html
>
> http://www.analog.com/en/products/rf-microwave/iq-modulators-demodulators/iq-demodulators/adrf6850.html
>
> some manufacturers may even have IQ transceivers on a chip.
>
> :)
>
> Sebastien
>
>
> Le 10/01/2018 à 14:52, Jeroen Vreeken a écrit :
>> On 01/10/2018 02:11 PM, Sebastien F4GRX wrote:
>>> have a look at the hermes lite 2 ( http://www.hermeslite.com )
>>>
>>> It is in the process of being finalized, and can work with a raspi host.
>>>
>>>
>>> I am also working on this: https://github.com/f4grx/hn70ap
>>>
>>> Not SDR, more SDFSK (with a si4463)
>>>
>>> some boards are being made right now.
>>>
>>> freedv software can definitely work on this.
>>>
>>> gps and battery can be added later in a v2.
>>>
>>>
>>> dra818 is cool but you get the same problem as dstar and other stuff:
>>> very
>>> suboptimal AFSK over FM...
>> I know, but the FM repeater already exists and can be used relativly easy.
>> What I would really like is a module like the dra818, but capable of SSB
>> (or IQ).
>> Maybe my next project will be a 'HT2000' to as a companion to the
>> SM2000
>>
>> 73,
>> Jeroen PE1RXQ
>>
>>
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Re: [Freetel-codec2] FYI: mode 2400B handheld

[Sebastien F4GRX]

Let's build a module with these:

http://www.analog.com/en/products/rf-microwave/iq-modulators-demodulators/iq-modulators/adrf6755.html

http://www.analog.com/en/products/rf-microwave/iq-modulators-demodulators/iq-demodulators/adrf6850.html

some manufacturers may even have IQ transceivers on a chip.

:)

Sebastien


Le 10/01/2018 à 14:52, Jeroen Vreeken a écrit :
> On 01/10/2018 02:11 PM, Sebastien F4GRX wrote:
>> have a look at the hermes lite 2 ( http://www.hermeslite.com )
>>
>> It is in the process of being finalized, and can work with a raspi host.
>>
>>
>> I am also working on this: https://github.com/f4grx/hn70ap
>>
>> Not SDR, more SDFSK (with a si4463)
>>
>> some boards are being made right now.
>>
>> freedv software can definitely work on this.
>>
>> gps and battery can be added later in a v2.
>>
>>
>> dra818 is cool but you get the same problem as dstar and other stuff: very
>> suboptimal AFSK over FM...
> I know, but the FM repeater already exists and can be used relativly easy.
> What I would really like is a module like the dra818, but capable of SSB (or 
> IQ).
> Maybe my next project will be a 'HT2000' to as a companion to the SM2000
>
> 73,
> Jeroen PE1RXQ
>
>
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Re: [Freetel-codec2] FYI: mode 2400B handheld

[Jeroen Vreeken]

On 01/10/2018 02:11 PM, Sebastien F4GRX wrote:

have a look at the hermes lite 2 ( http://www.hermeslite.com )

It is in the process of being finalized, and can work with a raspi host.


I am also working on this: https://github.com/f4grx/hn70ap

Not SDR, more SDFSK (with a si4463)

some boards are being made right now.

freedv software can definitely work on this.

gps and battery can be added later in a v2.


dra818 is cool but you get the same problem as dstar and other stuff: very
suboptimal AFSK over FM...

I know, but the FM repeater already exists and can be used relativly easy.
What I would really like is a module like the dra818, but capable of SSB 
(or IQ).

Maybe my next project will be a 'HT2000' to as a companion to the SM2000

73,
Jeroen PE1RXQ


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Re: [Freetel-codec2] FYI: mode 2400B handheld

[Sebastien F4GRX]

very interesting! I did not know that! Thanks for sharing!

Sebastien


Le 10/01/2018 à 14:48, Jeroen Vreeken a écrit :
> On 01/10/2018 02:14 PM, Sebastien F4GRX wrote:
>> Reading again these boards are more the basestation part of the system.
>>
>> But a freedv handheld is also something that can be VERY interesting.
>>
>> As well as inventing a real solid open digital voice architecture made by 
>> hams
>> for hams.
>>
>> Something that could work with open standards, like hamnet, SIP, ham calls, 
>> and
>> a decentralized routing database to avoid any SPOF...
> http://dmlinking.net
>
>
>
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Re: [Freetel-codec2] FYI: mode 2400B handheld

[Jeroen Vreeken]

On 01/10/2018 02:14 PM, Sebastien F4GRX wrote:

Reading again these boards are more the basestation part of the system.

But a freedv handheld is also something that can be VERY interesting.

As well as inventing a real solid open digital voice architecture made by hams
for hams.

Something that could work with open standards, like hamnet, SIP, ham calls, and
a decentralized routing database to avoid any SPOF...

http://dmlinking.net



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Re: [Freetel-codec2] FYI: mode 2400B handheld

[Sebastien F4GRX]

Reading again these boards are more the basestation part of the system.

But a freedv handheld is also something that can be VERY interesting.

As well as inventing a real solid open digital voice architecture made by hams
for hams.

Something that could work with open standards, like hamnet, SIP, ham calls, and
a decentralized routing database to avoid any SPOF...

sebastien


Le 10/01/2018 à 14:11, Sebastien F4GRX a écrit :
> have a look at the hermes lite 2 ( http://www.hermeslite.com )
>
> It is in the process of being finalized, and can work with a raspi host.
>
>
> I am also working on this: https://github.com/f4grx/hn70ap
>
> Not SDR, more SDFSK (with a si4463)
>
> some boards are being made right now.
>
> freedv software can definitely work on this.
>
> gps and battery can be added later in a v2.
>
>
> dra818 is cool but you get the same problem as dstar and other stuff: very
> suboptimal AFSK over FM...
>
> Sebastien
>
>
> Le 10/01/2018 à 13:02, Adrian Musceac a écrit :
>> Hi Jeroen,
>>
>> This is a very interesting project. If there's anything I would
>> change, I would add a more powerful CPU, capable of running some other
>> applications, like chat, maps, email, pictures.
>> Otherwise you could end up for example receiving a position report but
>> no being able to plot it without an external computer. Have you
>> considered using an SBC instead?
>> Myself I am approaching this differently. I am pushing for a SDR
>> solution but I lack the skills to design a good frontend with small
>> dimensions. Components for ISM bands are plenty and cheap, not so for
>> ham bands.
>>
>> Regards,
>> Adrian
>>
>> On 1/9/18, Jeroen Vreeken  wrote:
>>> Inspired by the SM1000 I have been thinking about a project to make
>>> using it easier: A small handheld capable of mode 2400B.
>>> Nothing really fancy, but it should be able to show of some features
>>> (like FPRS position reports interleaved in an audio stream) while making
>>> communication in the field as simple as possible. And of course it
>>> should be an open design. Since the inspiration came from the SM1000 I
>>> would like to call it the 'HT1000'.
>>> The basic design would consist of:
>>>
>>>  - DRA818 FM transceiver module
>>>  - Small GPS receiver
>>>  - LiPo battery
>>>  - Atmel ATSAME70 cpu
>>>  - Speaker & mic
>>>  - Display and controls
>>>  - Glue circuitry to let it work together
>>>  - 3D printed housing
>>>
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Re: [Freetel-codec2] FYI: mode 2400B handheld

[Sebastien F4GRX]

have a look at the hermes lite 2 ( http://www.hermeslite.com )

It is in the process of being finalized, and can work with a raspi host.


I am also working on this: https://github.com/f4grx/hn70ap

Not SDR, more SDFSK (with a si4463)

some boards are being made right now.

freedv software can definitely work on this.

gps and battery can be added later in a v2.


dra818 is cool but you get the same problem as dstar and other stuff: very
suboptimal AFSK over FM...

Sebastien


Le 10/01/2018 à 13:02, Adrian Musceac a écrit :
> Hi Jeroen,
>
> This is a very interesting project. If there's anything I would
> change, I would add a more powerful CPU, capable of running some other
> applications, like chat, maps, email, pictures.
> Otherwise you could end up for example receiving a position report but
> no being able to plot it without an external computer. Have you
> considered using an SBC instead?
> Myself I am approaching this differently. I am pushing for a SDR
> solution but I lack the skills to design a good frontend with small
> dimensions. Components for ISM bands are plenty and cheap, not so for
> ham bands.
>
> Regards,
> Adrian
>
> On 1/9/18, Jeroen Vreeken  wrote:
>> Inspired by the SM1000 I have been thinking about a project to make
>> using it easier: A small handheld capable of mode 2400B.
>> Nothing really fancy, but it should be able to show of some features
>> (like FPRS position reports interleaved in an audio stream) while making
>> communication in the field as simple as possible. And of course it
>> should be an open design. Since the inspiration came from the SM1000 I
>> would like to call it the 'HT1000'.
>> The basic design would consist of:
>>
>>  - DRA818 FM transceiver module
>>  - Small GPS receiver
>>  - LiPo battery
>>  - Atmel ATSAME70 cpu
>>  - Speaker & mic
>>  - Display and controls
>>  - Glue circuitry to let it work together
>>  - 3D printed housing
>>
> --
> Check out the vibrant tech community on one of the world's most
> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> ___
> Freetel-codec2 mailing list
> Freetel-codec2@lists.sourceforge.net
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Re: [Freetel-codec2] FYI: mode 2400B handheld

[Adrian Musceac]

Hi Jeroen,

This is a very interesting project. If there's anything I would
change, I would add a more powerful CPU, capable of running some other
applications, like chat, maps, email, pictures.
Otherwise you could end up for example receiving a position report but
no being able to plot it without an external computer. Have you
considered using an SBC instead?
Myself I am approaching this differently. I am pushing for a SDR
solution but I lack the skills to design a good frontend with small
dimensions. Components for ISM bands are plenty and cheap, not so for
ham bands.

Regards,
Adrian

On 1/9/18, Jeroen Vreeken  wrote:
>
> Inspired by the SM1000 I have been thinking about a project to make
> using it easier: A small handheld capable of mode 2400B.
> Nothing really fancy, but it should be able to show of some features
> (like FPRS position reports interleaved in an audio stream) while making
> communication in the field as simple as possible. And of course it
> should be an open design. Since the inspiration came from the SM1000 I
> would like to call it the 'HT1000'.
> The basic design would consist of:
>
>  - DRA818 FM transceiver module
>  - Small GPS receiver
>  - LiPo battery
>  - Atmel ATSAME70 cpu
>  - Speaker & mic
>  - Display and controls
>  - Glue circuitry to let it work together
>  - 3D printed housing
>

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Re: [Freetel-codec2] FYI: mode 2400B handheld

[Steve]

That's a neat CPU. By the way SV1AFN has some nice designs for the 818
chip (output filter, etc).

https://www.sv1afn.com/dra818.html

I was thinking that the only thing missing was:

1) a Doppler correction input for satellites.
2) PPS output from GPS for syncing to time slice generator.

73/Steve

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[Freetel-codec2] FYI: mode 2400B handheld

[Jeroen Vreeken]

Hi,

For a while now our local repeater PI2EHV has been capable of receiving 
both analog FM and FreeDV mode 2400B.

However the amount of digital users is low (not a big surprise).

Inspired by the SM1000 I have been thinking about a project to make 
using it easier: A small handheld capable of mode 2400B.
Nothing really fancy, but it should be able to show of some features 
(like FPRS position reports interleaved in an audio stream) while making 
communication in the field as simple as possible. And of course it 
should be an open design. Since the inspiration came from the SM1000 I 
would like to call it the 'HT1000'.

The basic design would consist of:

- DRA818 FM transceiver module
- Small GPS receiver
- LiPo battery
- Atmel ATSAME70 cpu
- Speaker & mic
- Display and controls
- Glue circuitry to let it work together
- 3D printed housing

As of last night the first step is working: an ATSAME70 running 
freedv_rx() and freedv_tx() between two AD converters and two DA 
converters. Next step will be connect a DRA818 module so I can actually 
test on air.


73,
Jeroen PE1RXQ



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