Connect a Soundmodem with my CB radio?

[Lord of nothing]

A friend of mine sold me an Soundmodem he dont need anymore: SCU-17
Here is the Manual: http://www.yaesu.com/jp/manuals/ol/SCU-17_OM_ENG_JPN_EAK21X700.pdf
I got some plugs from Ebay.
How to wire it with my Radio?!

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PIN 1  Microphone NF 
PIN 2  PTT-RX contact (on GND during reception) - also for  NF uncoupling packet radio
PIN 3  PTT-TX contact (on GND during transmission) 
PIN 4  UP/DOWN button (caution, special circuit for AE 5890 EU)
PIN 5  Ground, shielding
PIN 6  Power supply for electrets microphone (or other accessories)
And what kind of cable do i need for?!

[Lord of nothing]

No idea?
I never have tried connect a radio to an sound modem.

[Lord of nothing]

  Can someone help me to connect the CB Radio with the Soundmodem?
I have no clue how it should work. What kind of Cable I need and how its stuck together.
THX!

[IanB]

Can someone help me to connect the CB Radio with the Soundmodem?
I have no clue how it should work. What kind of Cable I need and how its stuck together.
THX!

You have provided the manual in the first post. The unit is designed to connect a computer to a radio transceiver. After making the physical connection the computer will need to have suitable software to drive it. I do not know if this device is meant to work with a CB radio.

The details of what kind of cables you need and how to connect things together are fully explained in the manual. If you have trouble understanding that level of technical detail then maybe you can try to find a local ham radio club to join where there may be people to help you?

[Lord of nothing]

After making the physical connection the computer will need to have suitable software to drive it.

thats no problem there are software who is used by ham radio operators to and dont require an radio amateur id. The Transfer Mode are the Same. Its PSK what is think.

The details of what kind of cables you need and how to connect things together are fully explained in the manual.

hmm no...
shield, unshielded, diameter,...?!

you can try to find a local ham radio club

there are just for radio amteurs  and the people are very selfish and think the know everything about RF stuff.    Old People who like to sitt with a beer in there hand in a Bar and argue around who bad DMR, Tetra, Nextedeg is and how good Short Wave is for an emergency communication. 

there may be people to help you?

I have 2 "friends" who are Radio Amateurs and the say just "hack it together".  As an total noob I have NO idea how! I live just in an Apartment and have not that much tools or spare parts.
That mean I have to order everything who I need.

[Lord of nothing]

Can someone help me what kind of cable do I need? 

[Lord of nothing]

hmm?!

[TheDane]

there may be people to help you?

I have 2 "friends" who are Radio Amateurs and the say just "hack it together".  As an total noob I have NO idea how! I live just in an Apartment and have not that much tools or spare parts.
That mean I have to order everything who I need.

First:
It seems your plug pin out is missing audio output, hence your sound card isn't capable of decoding the received transmissions from the radio, when purely using the one plug you have described. You're most likely going to need another plug, and attenuate the output so the sound card isn't over modulated.

I suggest to get the reception up and running before you start to transmit.


Second: Beware of ground currents/loops. HF signals can destroy computers, if the energy flows in uncontrolled ways.

You say you live in an apartment building. Do you get good reception on voice, using the frequencies you are allowed to use?
If your radio reception and transmission quality is "deaf ear", it's going to be a no fun project I suppose.

Another thing - public (free) Rx/Tx channel bandwidth is limited, usually 5-10-12.5 kHz, which leaves the baud rate very low. Packet radio on HF/VHF is usually 1200 baud (1.2k - verrrrry slooooooooow!!!!!!) so if you plan to get an internet feed through this way, it's going to be the slowest internet you have ever experienced 

If you can get your friends to help you (well teach you - real nerds love that thing), I would suggest to invite them over, and y'all have a nice 'hack-day' 

[Lord of nothing]

Hi
I annoyed a German Speaking Forum until someone emplane to me what the information in the Radio Manual mean.
In the Attachment is the wiring how it should work.

It seems your plug pin out is missing audio output, hence your sound card isn't capable of decoding the received transmissions from the radio, when purely using the one plug you have described. You're most likely going to need another plug, and attenuate the output so the sound card isn't over modulated.

thats why a sound modem is used. The have isolated Ports to prevent it and the pc from over powering and current leaking. 

Do you get good reception on voice, using the frequencies you are allowed to use?

First I use CB. That is legal the whole EU maybe the Sound Modem Thinks to I dont know. Here in Austria its legal.
I got someone on CB but nobody else. The problem quite nobody is use CB and some % of the freaks who use it use a Sound Modem.

If your radio reception and transmission quality is "deaf ear", it's going to be a no fun project I suppose.

Thats why I will get a Waterproofe CB Radio who have normal Audio Ports to use it for "Tracking". Over LTE I can controll/ send commands and see if I can receive it with my Handheltradio.

usually 5-10-12.5 kHz

10khz on CB. 

Packet radio on HF/VHF is usually 1200 baud (1.2k - verrrrry slooooooooow!!!!!!) so if you plan to get an internet feed through this way, it's going to be the slowest internet you have ever experienced

haha I have an LTE Contract for Mobile use 5€ 1GB its enough.

https://en.wikipedia.org/wiki/Olivia_MFSK
https://de.wikipedia.org/wiki/ROS_(Betriebsart) (DE)
https://en.wikipedia.org/wiki/List_of_amateur_radio_modes#Other_modes (ROS ENG)

If you can get your friends to help you (well teach you - real nerds love that thing), I would suggest to invite them over, and y'all have a nice 'hack-day'

The want to teach me how to make a Joint and Drink Beer.   

[TheDane]

Understanding the scope/mission is sometimes what's needed to complete the journey 
- thanks for updating me a bit more.

It sounds like a fun project, I remember when I was on packet a long time ago. It's a fun way to learn about RF and digital/analog signal transmission, if you have the dedication and/or people, clubs, forums, schools etc. to learn from.

I do not know the specifics about the devices you're using, but usually PTT means 'Push To Talk'.

From what I read from the picture provided (sorry, I haven't read through the datasheet you provided entirely - it's nice to see that it is galvanic separated on all I/Os but USB) the device is keying the receiver into either transmission mode, or reception mode.
I could be wrong on this - but if I'm not, you won't get any RX data/audio on this pin. Pin 2 could be audio input into the modem, and if it is - and the modem shorts this to ground at (random?) times, make sure the radio output can handle a short.
(Quote: PIN 2  PTT-RX contact (on GND during reception) - also for  NF uncoupling packet radio )

Tx data/sound should go into the microphone input, at the right drive levels/impedance, so not to over modulate the transmitted audio. Over modulation isn't useful - it creates all sorts of problems 
Electret microphone inputs could require some hacking, as they can be DC biased. I suggest reading more:
https://en.wikipedia.org/wiki/Electret_microphone

[Lord of nothing]

Maybe someone can look over if something is wrong?

It's a fun way to learn about RF and digital/analog signal transmission

I would say there isnt that much to learn. Maybe which freq is planed for what kind of transmission like Radio, Sea, Air,... In Denmark you should get Sea Traffic and that kind of stuff.

if you have the dedication and/or people, clubs, forums, schools etc. to learn from.

Nada just the Web who teach me the wrong side of Transmissions. 

From what I read from the picture provided (sorry, I haven't read through the datasheet you provided entirely - it's nice to see that it is galvanic separated on all I/Os but USB) the device is keying the receiver into either transmission mode, or reception mode.
I could be wrong on this - but if I'm not, you won't get any RX data/audio on this pin. Pin 2 could be audio input into the modem, and if it is - and the modem shorts this to ground at (random?) times, make sure the radio output can handle a short.
(Quote: PIN 2  PTT-RX contact (on GND during reception) - also for  NF uncoupling packet radio )

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PIN 1  Microphone NF
PIN 2  PTT-RX contact (on GND during reception) - also for  NF uncoupling packet radio
PIN 3  PTT-TX contact (on GND during transmission)
PIN 4  UP/DOWN button (caution, special circuit for AE 5890 EU)
PIN 5  Ground, shielding
PIN 6  Power supply for electrets microphone (or other accessories)
The support was answer me:

an PIN2  liegt das Empfangs Signal  (Audio Wiedergabe /  Lautsprecher ) . wird der PIN2 gegen Masse geschaltet, wird der Geräte Lautsprecher eingeschaltet.

the quick and dirty translation mean on Pin2 is for "Loudspeaker". When Pin2 is put to Ground the Radio put there the Audio out. But how to put to Ground? Mean just connect with the Sound moden?!

[TheDane]

I have no idea about your radio, but the datasheet you linked to above gives a little info about the sound modem:

Data Jack
:
PTT: Maximum output +25 V, 50 mA (open collector)
FSK: Maximum output +25 V, 50 mA (open collector)
DATA-IN: 100 mVrms @ 10 k Ohms
DATA-OUT: 100 mVrms @ 600 Ohms
FSK/PTT Jack
:
PTT:  Maximum output +30 V, 250 mA (open drain)
FSK:  Maximum output +30 V, 250 mA (open drain)


AUDIO Jack
:
AUDIO-IN: 100 mVrms @ 600 Ohms
AUDIO-OUT: 100 mVrms @ 600 Ohms


To me it seems the sound modem 'shorts' the pin(s), and expects the radio to supply signals accordingly to the 3.5mm stereo jacks, or to transmit the signals sent.
PTT/FSK input/outputs are opto-couplers/transistors according to the datasheet, and you can sink/source the current at max. voltage given above.
The datasheets gives some info about changing mode between PTT and FSK, and signal attenuation - it's on page 13.

(FSK is the modulation standard most commonly used on AX.25 packet - here's something to learn/read about: https://en.wikipedia.org/wiki/Frequency-shift_keying )

- my not so native German translates the text into: When pin 2 is shorted, audio is 'transmitted' to you through a built in speaker.. Spreche sehr gute Deutch, aber ikke så længe af gangen :-)

[Lord of nothing]

  I will use just the Sound Based Mode like ROS, Olivia und PSK31.

[TheDane]

 

How did my German-English translation fare, in regards to the speaker / pin 2
- I presume you live around Wienerwald according to your tag line, and you said earlier you were on a German speaking forum - hence your German must be a lot better than my English 

[Lord of nothing]

So i connected the Radio with the Sound Modem and sadly to the lack of information i dont know if the Audio level  are rite. The problem with SSB is when the Audio Level is to strong the signal is bad. 

[TheDane]

If you add a potmeter in series with the audio signals (one for Rx and one for Tx), you should be able to attenuate the signals to the correct level quite easily.

https://en.wikipedia.org/wiki/Potentiometer

I suggest you read this blog, it explains how audio attenuation is done - though it is most likely overkill in your case to make a PCB and doing -1/-3dB steps. https://www.tubecad.com/2011/04/blog0204.htm

[Lord of nothing]

  the most annoying problem at the moment is the CB Radio inter-fear the Lan/ Fiber Media Converter.
WTF... 
What is wrong with the Media Converter. Full Metal Case and just connect with the Switch and the Glas Fiber.