Re: DRAWS™ and YAESU FTM-100 for analog and digital modes

Bernard f6bvp / ai7bg

Hi John,

I performed audio level adjustment for I found that FTM-100DE VHF
transmitted signal from DRAWS modem was spreading around the TX frequency.

After adjusment this is the result of :

===== ALSA Controls for Radio Tansmit =====
LO Driver Gain L:[15.00dB] R:[15.00dB]
PCM L:[-31.00dB] R:[-31.00dB]
DAC Playback PT L:[PTM_P3] R:[PTM_P3]
LO Playback CM [Full Chip CM]

===== ALSA Controls for Radio Receive =====
ADC Level L:[0.00dB] R:[-5.00dB]
IN1 L:[Off] R:[Off]
IN2 L:[10 kOhm] R:[10 kOhm]
CM L:[10 kOhm] R:[10 kOhm]

Here is how I proceeded for level adjustement using alsamixer.
I have set a second yaesu device with a Raspberry Pi, UDRC II modem and
audacity to listen to my packets.
While recording the audio signal, I first changed LO driver gain in
I then stepped down the PCM and then increased it again until the
received signal did not increase any more.

With above levels, the transmitted 1200 bauds FSK signal was clean and
it was copied correctly by adjacent APRS repeater stations.

On average received APRS frames are reported to have an audio level
around 20. AFSK frames are perfectly decoded.

73 de Bernard, f6bvp

p.s. there is a typo in first line of dump:
"Radio Tansmit =====" should be Radio Transmit =====

Le 06/04/2019 à 18:22, John Spoonhower a écrit :
I am curious about what are the audio level settings for this radio. Can
you please post the results of ""?

On Sat, Apr 6, 2019 at 12:15 PM f6bvp <
<>> wrote:


I just want to report the successful use of
Data Cable, 10-pin mini-DIN to 6-pin mini-DIN, for FTM-400DR/FTM-100DR,
This lets you use DRAWS hat modem and Direwolf for AX.25 packet

FTM-100DE is an interesting mobile VHF/UHF FM rig that I am using at
home for 1200/9600 bauds AX.25 APRS application.
As a transition device it has both "analog" and new digital C4FM modes.
Data plug is a 10 pin mini DIN while UDRC II and DRAWS have mini DIN 6
plugs. This is the reason I had to use a compatible data cable.

Bernard, f6bvp


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