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Messages - SP5WWP

1
Technical / Re: TR-9 analog mode?
March 04, 2020, 08:19:59 pm
Analog mode capability in TR-9 is 100% confirmed. A quick test with ADF7021 showed it's possible. I have even added a CTCSS tone of 127.3Hz to the audio stream and it worked fine.
2
Technical / Re: TR-9 - case
March 04, 2020, 08:17:35 pm
We have almost finished developing the mainboard, the dimensions are approximately 45x105mm.
3
Technical / Re: Error Correction Coding
March 04, 2020, 08:16:27 pm
I have encoded the Link Information Channel (LICH) with 24,12 Golay (since its partitioned into 48-bit chunks). The rest is going to be convolutionally coded with constraint K=5 and punctured (exactly like in NXDN, but with a different puncturing matrix).

Check this thread for details (post #1):
https://m17project.org/forum/index.php?topic=6.msg6#msg6
4
I don't think that measuring RSSI once per transmission is a good idea. We are going to use ping for that (ask repeater for response).
5
Technical / Re: M17 frame description
March 04, 2020, 07:59:54 pm
Please take a look at my newest proposal (I have edited post #1).
6
Technical / Re: M17 Reflector
February 16, 2020, 06:41:42 pm
Hello!
Sorry for a late reply. No plans for reflectors yet. We are still working on hardware (handheld) and the protocol spec.
7
Technical / Re: TR-9 Frequencies?
February 08, 2020, 10:32:54 am
I have successfully tuned the ADF chip from 430 to 460 megs. Gonna check 420..430 range too.
8
General discussion / Re: Podcasts
February 07, 2020, 08:11:38 pm
Yeah, M17 appeared in at least 3 different podcasts :)
9
Technical / Re: New version of M17_ANL !
February 07, 2020, 08:10:30 pm
Yeah, an MMDVM HS hat.
10
Technical / Re: TR-9 - RF power amplifier
February 07, 2020, 08:07:30 pm
Output power: 1W on low setting, 3 to 5W on high
Gain: ADF can supply 13dBm. See diagram below.
Linearity: we don't care about linearity. You got it right.
Stability, technology: See diagram below.
Supply: 7.4V from Li-Ion.
Regulatory: glad to be in a place, where we don't have to care about FCC :) hehe. We are going to measure that. We use a basic LC pi-topology filter, see the schematic for details.

11
Technical / Re: ADF7021 problem
February 06, 2020, 06:18:41 pm
Fixed. The problem was the TCXO which didn't give CMOS compatible output. I had to set bit B12 in register 1 to make it work.
12
Technical / ADF7021 problem
February 01, 2020, 06:58:09 pm
Does anyone have mmdvm board and can help me? I have a problem with writing to ADFs registers. I can provide a hex for STM reflashing.
13
Technical / Re: TR-9 Frequencies?
January 29, 2020, 07:47:21 am
Hello and welcome to our forums!
We want to try the 70cm band first. That would be 430-440MHz.
14
Technical / Re: Overall Spec?
January 26, 2020, 09:58:32 pm
15
Technical / Re: TR-9 - schematics and firmware
January 20, 2020, 08:58:55 pm
TR-9 schematic is ready!