FT847 and digirig cables

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I’ve done a search and only found 2 topics that dealt with the FT847 and digirig. And I’m not sure which is really right because they seem to both be conflicting to what they other says.

So my question is, what cables do I need to use with the FT-847 and digirig?

I’ll mainly want to attempt FT8 on 2M, that was the whole reason I got this radio. But I wouldn’t mind using it for other digital modes and other bands as well.

I originally got the digirig for the FT-891, so I got those cables (even though I only need the audio cable for that radio).

I’m mainly wondering do I need to do something similar and use a RS232 cable for cat control on the 847 like the USB cable on the 891.

Right now I have one that goes to USB, but I’ve seen that there’s this one that some Yaesu radios use directly to digirig, but doesn’t mention my model specifically.

I saw that there’s the pair, or just the rs232 itself.

So can anyone give me any insight to what I need?

Thanks!

2

I would go with this post:

You’ll need to homebrew an audio/PTT cable. Optionally, if you also want CAT control, you’ll need to make sure that Digirig is in RS-232 configuration and add a crossover DB9 cable. I have those in stock, but they’re different from the regular DB9 cables so leave me a note if you want that variant.

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To be sure I got it right,
On the 847 it’s a 3.5mm TRS

On the digirig it’s a 3.5mm TRRS

Tip of TRS to TRRS ring 1
TRS ring 1 to TRRS tip
TRS Ground/sleeve to TRRS ground/sleeve
TRRS ring 2 bridged to TRRS ring 1

Correct?

I’ll need the homebrew cable, and the correct rs232 cable? And that’ll be it?

4

You’ll also need a 2K resistor, not just short between ring 1 and ring 2 on TRRS side.
As for RS-232 cable - you only need it if you prefer to add optional CAT control. I’ll be able to ship it after my return from the break at the end of the month. Please make sure to leave a note or message me the order ID.

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Thanks! I read the other topic mentioning the cable and misread it, I thought a resistor wasn’t needed but I see now that it was the capacitor instead.

I’ve never built anything like this before, but I don’t have any problem soldering.

MFG_10-00336
MFG_10-00336640×640 24.5 KB

How would the easiest way be to build it?
Get a cable similar to the one I’ve included, a TRS, and then another TRRS with the 4 wires, and have a small block in the middle to put the connecting wires and resistor similar to how some cables like the yaesu scu58 is?

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An easy way to prototype would be with something like this (TRRS variant):

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So I got the cable ordered, and the audio cable made. Two questions now.

I saw that the digirig needs to be put in rs232 mode by soldering the spot on the board, is that the only way?
And if so, will that make it so that I can’t use cat control on something that doesn’t use rs232?

And I’m not home to check my settings for the radio, but hopefully what I can provide is enough to get an idea.

The home brew cable I made kind of works.
I tried it with wsjtx, and it’ll decode.
When it tries to transmit, it’ll rapidly click but never transmit that I can tell.

I got the cable made and tested with a multimeter to make sure it’s wires line up right. Does the gauge of wire that I use matter?I think it was 26

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Re. RS-232 serial port configuration: yes, you’ll need to cut existing traces and make solder connections between the pads. More info on this here:

and here:

The gauge of the wires don’t matter. This is a concern for the power cables, but typically not an issue with signal cables.