Re: [Freetel-codec2] Windows IDE for STM32F4

2017-04-12 Thread Matthew Cook
David, I'm also using System Workbench for my STM32F experiments. 73 Matt VK5ZM On 12 April 2017 at 15:08, Akshay Mishra wrote: > System Workbench for STM32 (http://www.st.com/en/ > development-tools/sw4stm32.html > > usual eclipse woes but works otherwise. > > On 12

Re: [Freetel-codec2] SM1000 on 2400 bps

2017-02-13 Thread Matthew Cook
Bohdan you'll find David is currently working on a new 700 bps codec and modem, with a focus to beat SSB performance with Digital Voice. I'm sure that he'd welcome any assistance porting the 2400B mode to the SM1000 platform. 73 Matthew VK5ZM On 14 February 2017 at 05:21, Yaremkiv Bogdan

Re: [Freetel-codec2] [digitalvoice] new 1000 and 700 bit/s Codec 2 candidates

2016-03-08 Thread Matthew Cook
Hi David, Definitely an improvement between the Newamp modes and the 700B. Intelligibility across all new modes was good, only minor artifacts like "tings" and general "sounded heavily processed" was all that jumped out at me. The Newamp modes seem to encode short vowels like "e" better, I found

Re: [Freetel-codec2] gain before ADC

2015-10-28 Thread Matthew Cook
David, If you're going to use a diode mixer then terminating *is* important, for your amusement/reading; http://www.robkalmeijer.nl/techniek/electronica/radiotechniek/hambladen/qex/2001/05_06/page45/index.html There are termination insensitive mixers to go with your termination insensitive

Re: [Freetel-codec2] gain before ADC

2015-10-28 Thread Matthew Cook
> > > On 29/10/2015 10:42 AM, Matthew Cook wrote: > > David, > > Ok that's just a straight direct conversion receiver. As Helmut has said > this is a different beast. The majority of your design decisions will be > made in the analogue world. > > Here

Re: [Freetel-codec2] gain before ADC

2015-10-28 Thread Matthew Cook
David, Ok that's just a straight direct conversion receiver. As Helmut has said this is a different beast. The majority of your design decisions will be made in the analogue world. Here's a few good worked examples for you to look at, it doesn't matter these are for HF the same rule applies

Re: [Freetel-codec2] 0dB and below

2015-09-23 Thread Matthew Cook
David, Why can I see a discussion paper or magazine article entitled "do you know your Eb/No?" *grin*. 73 Matthew VK5ZM On 24 September 2015 at 05:46, David Rowe wrote: > Nice work on the power measurement Helmut :-) > > I wanted to say a little about 0dB SNR and below

Re: [Freetel-codec2] 0dB and below

2015-09-23 Thread Matthew Cook
David > > On 24/09/15 10:19, Matthew Cook wrote: > > David, > > > > Why can I see a discussion paper or magazine article entitled "do you > > know your Eb/No?" *grin*. > > > > 73 > > > > Matthew > > VK5ZM > > > > On 24 S

Re: [Freetel-codec2] SM1000 phantom power

2015-09-09 Thread Matthew Cook
David, Provided people understand the limitations of phantom power then you're good. I have only implemented phantom power on transceiver cables that have an A+ rail (13.8V@1A). The majority of transceivers seem to have an 8V@30mA rail for biasing eletret microphones, these should be avoided