How Can I Improve My Digirig Setup for Better Performance?

Hello everyone,

I recently set up my Digirig interface for digital modes;, and I am experiencing some issues with performance. I am using it primarily with FT8 and other PSK modes. While everything seems to be connected fine, I have noticed some inconsistencies in signal quality and connection reliability.

I have tried adjusting the levels on my sound card and made sure the cables are properly connected…, but I am still not getting the performance I expect.

Does anyone here have any tips or tricks to optimize the Digirig setup: ?? Specifically…, I am looking for advice on:

Improving signal clarity - Any tweaks for sound card settings or software: ??
Reducing interference - I have read about grounding techniques but unsure if they will help.
Software settings - Are there any recommended settings in popular digital mode programs for better results: ??

I would really appreciate any advice from experienced users here.

Thanks in advance !!

With Regards,
MarceloDevops

signal clarity:
we’ll need to know what your transceiver is and how it is connected to the digirig interface.

there are different tips/tricks for connected to a fixed audio output like from the ACC jack or a variable audio output from the speaker jack.

with a fixed output, you just have to look at the computer ‘mic’ slider and options.
make sure AGC is not checked. adjust the slider until your radio software show a 1/2 to 2/3 scale on that input. that’s usually my sweet spot on any software.

on the radio itself, AGC is usually turned off for digital modes.
this prevents the radio from dialing down the rf gain when a strong station is transmitting, effectively reducing the signal of all the other signals in the same bandspace.

wsjt-x waterfall for example, you have a bunch of 'lightly colored signals and one white hot signal. the radio AGC will ‘normalize’ the rf gain on that white hot signal. this of course ‘quiets’ the weaker signals on the waterfall. sometimes to the point of no decode.

now, interference:
YES, grounding is probably the least obsessed over part of any ham station.
grounding well/properly will give all your equipment a SHORT/FAST path to ground.

this keeps the devices from trying to find a path to ground through OTHER DEVICES.

along with grounding, think ROUTING.
routing your cables, coax, and power cords in such a way that they do not cross over each other or lay parallel right on top of each other.

something as simple as a usb charger + cable/cord right next to coax/coax connector can cause RF noise on your receive.

lastly, the audio OUT of your PC into your radio.
make sure the PC sound has NO enhancements checked.
locate your RADIO ALC meter
send a test tune from the pc software like wsjt-x
while looking at your ALC meter slide up the volume slider until the ALC is in the ‘appropriate’ position.

example:
my ICOM radios produce quality audio from 1 to 3 on the ALC scale. above 3, the ‘limiter’ starts actively keeping output ‘down’. above 4/5, the human ear can hear the ‘altering’ of the audio output. so i adjust the WSJT-X output slider (power) until i get right at 3. then for me, i adjust power output from the radio itself. that’s just me. you can slide the software slider down to decrease power but that means you are sending less AUDIO to the radio. like whispering to it. i prefer to send a full audio signal to the radio and just turn the power on the radio down.

same thing, different radio:
my xiegu g90/x5105 perform well with ALC as close to ‘100’ on the meter as i can get.

that’s a few off the top of my head.

from back in psk31days, this has worked for me.

:slight_smile:
good luck
kb0wlf

While this is a noble thought, it’s not based entirely on reality. Yes, a noisy radiator can induce signal into other lines, however, it normally needs to be obnoxious to do so (and yes, there are plenty of obnoxious devices out there.)

Cable routing falls into a touchy subject for many, as the primary issue is RFI. Many people recommend ferrites on “all” interconnected cables, however, that is a band aid at best. It may mitigate your issue, but solving the actual root cause eliminates all that work. End fed antennas are the leading producer of RFI, since they rely on the shield of the feedline and associated connected metallic things to be the counterpoise.

Until an operator learns how to properly configure their antenna system, they likely will continue to experience issues. We must consider, that the infamous “tuner” that sits somewhere in the shack, is normally connected with coax that isn’t fully shielded. Plain RG types are in the 88% range, which means there is leakage, even if the antenna accepts 100% of the power. The operator could switch to 100% shielded feedline to eliminate that leakage, solving a myriad of potential issues. Of course, the radio itself may be leaky. A lot of radios today aren’t fully shielded.

It all comes back to understanding RF, which most amateurs don’t.

I have HUNDREDS of low voltage interconnects, all bundled together in parallel, with multiple feedlines in the same bundle, and no EMI. Certainly I have EMI between low voltage cables. When one is identified as being a bully, it is replaced with a different type, shielded if it wasn’t previously. Ethernet, serial, ttl, unbalanced line audio, HIDs, you name it, it’s in the bundle.

As a system integrator, I can assure you that the unnecessary use of ferrites to mitigate bad design is not a goal.

Matt
AL0R

You didn’t mention what radio you use, or what quality and reliability issues you are experiencing.

I work with a number of non-amateur organizations that utilize parallel tone and OFDM systems. Frequently, an amateur will join one of those orgs and either have limited success or a station that previously was fine suddenly has “quality and reliability” issues.

Audio levels, in and out of the radio.
Transmit and receive filter widths.
No DSP, DNR, NB, EQ, etc.
Windows sound config (no AGC, enhancements, etc.)

Matt
AL0R

If you suspect outside interference, flip off breakers individually until the interference goes away, then seek out individual appliances. Wrap the power cord of the offending appliance through a torroidal mix 31 ferrite.

Incoming audio to computer should be tuned low, per the recommendations of the software you’re using.

Audio output tuning is more challenging, and specific to your model radio. Some radios like some ALC, some want no ALC at all. Best to experiment with attenuation while observing from a distance. So youll need to have a friend watching your signal for splatter on a waterfall and listening to the audio for coarseness. Alternatively watch your signal through a nearby online SDR, or set up an internet connected VNC connection to a secondary station some miles away and attenuate your outgoing signal until signs of overdriving disappear.

This article has some tips on tuning your audio settings. Since it applies to FT8 it is also good advice for JS8Call.

I discovered that with my FT-897, any amount of ALC on the meter correlates with splatter and trash slopping up the band from my offset on JS8Call.