Yaesu FT-450D setup issues

I’m having an issue with my 450D and a new v 1.9 digirig. The serial connection just doesn’t work. If I use identical settings with another serial adapter it works fine.

The audio is also not good on my new digirig, it much worse than an older v 1.5 I’ve been using (see attached screenshots form WSJT-X). These were taken with the 1.5 at 10% audio gain and the v 1.9 at 100% audio gain.

I almost think I got a bad sample.

Digirig 1.5 - clean audio, lots of FT8 decodes:

Digirig 1.9 - garbage audio, lots of birdies, almost no FT8 decodes:

This could be a cable issue, something like floating ground. Do you use rev 1.5 cables (TRS) with your rev 1.9 Digirig (TRRS)?

For the 1.5 I made my own cable. For the 1.9 I used new cables purchased with the digirig.

Re. audio: FT-450 uses 6 pin mini din. Please check the continuity to make sure cable has no issues:

For CAT control, it’s DB9 cable with straight pinout:

Let me know the results of the pinout test and we’ll take it from there.

So I got some weird results for the audio cable:

  • Tip - continuity to Pin 3
  • Ring 1 - Pin 2
  • Ring 2 - Pin 4
  • Sleeve - Pin 1 okay but No continuity with Shield
    This would make sense that the audio isn’t any good, the radio Audio Out isn’t even connected. Not sure how I’m getting any signal at all.

The serial cable is wired as you have shown, however, after looking at the manual for the 450D I wonder if this is correct for this radio. In the manual it has Serial Pin 2 as Serial OUT and Pin 3 as Serial IN. You have Pin 2 labeled as Rig RX, wouldn’t that be Serial IN which is Pin 3? I have a null modem adapter at work that I can try and see if that fixes the issue. Not sure if you sell more than one configuration of this cable, but this may just be the wrong version.

See attached screenshot from the manual.

I’m going to put together a test cable to see if the audio issue resolves. I’ll let you know later this week.

Thanks.

Joe,
Sleeve of TRRS should be connected to pin 5, not 1. Please make sure you account for solder side vs pins side perspective. Here is pin numbering from the outside:


Ground (5) is leftmost while wide side is at the top.

This cable is for CAT only and has no effect on audio. Audio cable is the one with miniDin6 connector on the other side. Did you have a chance to test the pinout there?

Let me rephrase for clarity.

I tested the Mini-DIN AUDIO CABLE with the following results:

  • Tip - continuity to Pin 3, NOT Pin 6 as shown on your drawing
  • Ring 1 - continuity to Pin 2, OK
  • Ring 2 - continuity to Pin 4, OK
  • Sleeve - continuity to Pin 1, but NOT with shell of Mini-DIN

This result leaves me to believe the reason my audio is bad is because radio Audio Out (Pin 6) isn’t even connected. Not sure how I’m getting any signal at all. I’m going to put together a test cable to see if the audio issue resolves. I’ll let you know later this week. This may just be an improperly assembled cable.

I tested the SERIAL CABLE with the following results:

  • Tip - Pin 2, OK
  • Ring 1 - Pin 3, OK
  • Sleeve - Pin 5, OK
  • Pins 7 & 8 shorted - OK

After looking at the manual for the 450D I wonder if this is correct for this radio. In the manual it has Serial Pin 2 as Serial OUT and Pin 3 as Serial IN. You have Pin 2 labeled as Rig RX, should that be connected to the Radio’s Serial RX Port or the TX Port? I wonder if the RX & TX are swapped and shouldn’t be in this case. I’ll experiment a little and see if I can get it to connect.

Thank you for the additional info.
Yes, it the serial pinout is reversed.

Re audio cable: you have a 9600 baud cable. Looking at the manual, it doesn’t appear that this model supports this pinout like most of other Yaesu transceivers using the same connector. You’ll need 1200 baud pinout from FT-8xx kit.

I’ll have both cables replaced. Arrangements in PM.

Just wanted to post that the replacement cables work perfectly. I have proper audio and rig control.

Thanks.

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