APRS DIY help for a noob.

[KM4DWS]

So I have an Icom 2730 and Mobilinkd 2.2 device being delivered sometime sooner or later (COVID19 willing). But I will need to make a cable to connect the devices together. Attached is a picture of the Icom Mic pinouts and the TNC instructions, it lists the pinouts for the TRRS output from the TNC.

I can wire an RJ45 if I know what to connect to which pin? Most of it is pretty clear to me but I am unclear on the grounds do I need to connect all the grounds to the same ground.

Ring 1 (TNC) to Pin 4 (RJ45)
Ring 2 (TNC) to Pin 6 (RJ45)
Sleeve (TNC GND) to Pins 5 & 7

Tip (TNC) to 3.5mm Ring 1 (Speaker)
Sleeve (TNC GND) to 3.5mm Sleeve (Speaker GND)

 

[Ubiety]

Suggest using a multimeter to check for connectivity, especially between the grounds on the radio.
I believe that MobilinkD sells a bunch of cables for different radios at reasonable prices.

 

[KM4DWS]

Suggest using a multimeter to check for connectivity, especially between the grounds on the radio.
I believe that MobilinkD sells a bunch of cables for different radios at reasonable prices.

Checked with them and while they have something for Icom HTs, the 2730a (best I can tell) needs input to go through the RJ45 and output through the speaker, which Mobilinkd did not have a cable for. So will need to find another source or create my own.

 

[GXAndy]

Hello from NC, too, Kaleb!

 

[KM4DWS]

Hello from NC, too, Kaleb!

GX as in Lexus too?

 

[Prerunner1982]

I had to make my own cable as well for a Yaesu ft-3100 and grounded through the 3.5mm audio jack.
Mic input and PTT through RJ mic jack.
Audio out (radio)/ Audio In (Mobilinkd) and ground through 3.5 audio jack.

Excuse my phallic looking TRS plugs.

 

[M Rose]

@KM4DWS you have to do just as @Prerunner1982 has done...

 

[KM4DWS]

I had to make my own cable as well for a Yaesu ft-3100 and grounded through the 3.5mm audio jack.
Mic input and PTT through RJ mic jack.
Audio out (radio)/ Audio In (Mobilinkd) and ground through 3.5 audio jack.

Excuse my phallic looking TRS plugs.

Thank you. I will try that idea first just ground to ground and let the Mic only use 2 pins.

 

[KM4DWS]

@KM4DWS you have to do just as @Prerunner1982 has done...

Thank you for the verification. Should be easy enough!

 

[M Rose]

Thank you for the verification. Should be easy enough!

It’s pretty straight forward... the hardest part is keeping all the wires organized so you don’t forget what you are soldering... I have a jig (piece of cardboard with holes in it) to keep the wires separate on both RJ45 cables and 4 pole 3.5mm audio jacks... this way I know which wire is which by what hole I put it through.

 

[KM4DWS]

Antenna showed up in UPS truck today... But the radio and mobilinkd are still MIA .

 

[KM4DWS]

It’s pretty straight forward... the hardest part is keeping all the wires organized so you don’t forget what you are soldering... I have a jig (piece of cardboard with holes in it) to keep the wires separate on both RJ45 cables and 4 pole 3.5mm audio jacks... this way I know which wire is which by what hole I put it through.

Always fun to deal with tiny cables and parts trying to achieve some precision with these oversized and clumsy clubs that I call hands and old warn out eyes.

 

[M Rose]

Always fun to deal with tiny cables and parts trying to achieve some precision with these oversized and clumsy clubs that I call hands and old warn out eyes.

Exactly my problem... then I suffer short term memory loss as well.

 

[Ubiety]

"these oversized and clumsy clubs that I call hands and old warn out eyes." + "short term memory loss" = my kind of people :)

Who are you and why are you calling me? :)

 

[KM4DWS]

Built the cable yesterday... Have not had a chance to test it yet but was not as bad as I thought it would but I will need to get some good flexible clamp things I see all over. I did not the patience to solder the cables together so if it fails I will pull it back apart and try again (after a trip to Harbor China Freight).

 

[Ubiety]

Built the cable yesterday... Have not had a chance to test it yet but was not as bad as I thought it would but I will need to get some good flexible clamp things I see all over. I did not the patience to solder the cables together so if it fails I will pull it back apart and try again (after a trip to Harbor China Freight).

Yeah, I need to drag the soldering iron out to the truck to finalize some connections. But they keep working... :)
glad you got your radio and have fun with the pi!