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What’s Included

Digirig DR-891 kit consists of:

• 1x Digirig DR-891 interface
• 1x Transceiver side MiniDin6 audio/PTT cable with black molding on Digirig’s end
• 1x Transceiver side USB-B cable with red molding on Digirig’s end

Required, but not included is a USB-C cable. Choose a data-capable USB cable of desired length that matches the connector type on your computing device at the other end. Several choices of excellent quality shielded USB cables with ferrite chokes are available in the Digirig Store.

Under the hood

Digirig DR-891 is the digital modes interface specifically designed for Yaesu FT-891 allowing the complete integration of the transceiver with computers, tablets or smartphones. One of the distinctive features of this radio is that it has a USB connection that is used for the serial CAT control while lacking the USB audio interface. Most of the other transceivers either have both or neither. As a result of this quirk the full integration of FT-891 for digital modes usually required two USB connections to the computer, that is until DR-891 came to be.

This interface uses a single USB-C connection to the computing device which is then fed into an internal USB hub. One of the downlink USB ports is routed to the colored socket on the transceiver side while another one is connected to the audio codec. Additionally, there is circuitry for fallback PTT methods, filtering and attenuation. Audio and hardware PTT connections are available through the black socket on the transceiver side.

Normally no hardware configuration is required, but if needed the fallback PTT methods can be individually disabled, and input audio attenuator can be enabled by cutting the traces between the solder pads on the back of the PCB.

Connections

The interface is connected to the computer, tablet or smartphone (computing device) using a USB-C port labeled “USB”. This connection facilitates digital communication and supplies power to the Digirig. See What’s Included section above for the information on the recommended USB cable.

Use included color-coded transceiver side cables to connect Digirig to your FT-891:

• ⚫ The 3.5mm TRRS jack with black molding is plugged into Digirig’s black socket labeled “audio”. On the transceiver’s side plug the connector into the MiniDin6 socket making sure you align the key to avoid damage. This connection facilitates ground connection, audio from the radio, audio to the radio and hardware PTT control line.
• 🔴 The 3.5mm TRRS jack with red molding is connected into Digirig’s colored socket labeled “USB”. On the transceiver side plug the connector into the USB-B socket aligning the chamfered sides. This is the pass-through USB connection for the USB-to-serial bridge inside of FT-891 which is used for the CAT control.

Devices

With radio connected and Digirig plugged into your computer, the system should detect Digirig’s sound card and radio’s USB-to-serial bridge. Open Device Manager or equivalent utility in your system to confirm that the OS can see the components. Take note of the number of the Enhanced COM port (higher of the two); you will need it for serial CAT control (AKA rig control). The Standard port may be used for hardware PTT, CW keying and other cases if a separate port is required.

If none of the devices are detected by your computer, then it’s likely due to the use of non-data capable USB cable.

If audio devices are detected, but no serial COM ports with the assigned numbers are shown, then it’s likely due to your system missing the drivers for the radio’s USB-to-serial bridge or radio’s USB cable not being connected. In case of a missing driver there will be a device entry under “other devices” group or similar displayed with a yellow exclamation mark. Use the links below for information on installing the necessary drivers:

• Driver Download
• Video of the installation process
• Yaesu’s driver installation instructions

If you wish to quickly access the Device Manager in Windows then create a shortcut pointing to “devmgmt.msc”. Another option is right clicking the start button and selecting “Device Manager” from the pop-up menu.

Transceiver Settings

Below is the list of the starter FT-891 settings for operating digital modes with Digirig DR-891. The transceiver settings can be accessed through a long press on the “F” button and navigating with the MULTI knob. Values shown in bold are non-defaults.

Finally, use the short presses of the “F” button and MULTI knob to access the “WDH” option and open the bandwidth to full 3000Hz. All other features except for MTR (your choice) and AGC (audio) should be turned off.

Some of the settings above are hard requirements, others are middle-of-the-road values subject to preference or operating conditions. For good explanation of the choices please refer to these resources:

• FT-891 Advance Manual (1806-F)  ( 12.98 MB )
• FT-891 Menu Settings guide by KN4MKB

If at some point things ever get out of hand, consider a clean start with a factory default settings (Menu 17-01).

System Audio Settings

With Digirig’s sound card detected by the computer, there should now be new Playback (speaker) and Recording (microphone) entries in the Sound Settings of the Control Panel or similar utility in your OS. Following adjustments are recommended:

• Rename the entries from default “USB Audio Device” to “Digirig” so they can be easily recognized when listed in the ham radio apps. You can also pick a different icon purely for aesthetic reasons.
• Move “Default Device” and “Default Communication Device” designations (indicated by green checkboxes) in both playback and recording groups from Digirig devices to your computer’s internal microphone and speakers. This will prevent the system’s normal sounds and media from getting on the air and radio’s received audio from getting into your VoIP call.
• Uncheck the “AGC” box in Digirig’s recording device under the “custom” tab.
• Leave sampling rate and bit depth at the maximum values
• Make sure no effects or enhancements are turned on for any of the Digirig’s audio devices.
• Set recording and playback levels to 50% as the initial values, this will have to be revisited later (see Software Audio Settings).
• “listed” checkbox can be enabled with the default audio device selected for the initial troubleshooting. This patches the audio received by the computer to the computer’s speakers for monitoring. Uncheck it later when everything works to your satisfaction.

Additionally:

• In Windows 11 edit system’s privacy settings to allow applications’ access to Digirig’s recording device (Microphone).
• Some systems may come with pre-installed software that manipulates the audio in the attempt to make voice calls sound better. Naturally, this wreaks havoc on the digital modes. Keep an eye out for any third-party utilities related to sound and make sure they stay away from Digirig’s audio.
• If you wish to quickly access the sound settings in Windows then create a shortcut pointing to “control.exe mmsys.cpl”. Another option is to right click the speaker icon next to the clock and then select “Sounds”.

Software Settings

Depending on the digital mode you wish to operate, you will need to run a specific software application. Here are some of the popular examples:

• WSJT-X for FT8 and FT4 – contesting style minimal QSOs over weak signals protocol.
• JS8Call – conversational QSOs over weak signals protocol (keyboard-to-keyboard or store-n-forward).
• Winlink Express + VaraHF or Soundmodem for email over radio.
• FlDigi for RTTY and other legacy conversational data modes.
• MMSSTV or YONIQ for images from terrestrial stations or ISS/satellites.
• Pinpoint APRS, APRSISCE/32 or other for location reporting and messaging.

There are numerous setup tutorials for specific ham radio applications made available on the web and in videos including discussions in the Digirig Forum. Most of the settings are similar regardless of the interface being used. Here we’ll focus on common settings pertaining to Digirig DR-891 that can be expected in every application.

⚠️ Note that Digirig must be plugged in and recognized by the computer before the software is launched otherwise the devices may not be visible to the app.

Software Audio Settings

Each digital modes software will have a soundcard or audio configuration section. Reference Digirig’s recording (input) and playback (output) audio devices in the corresponding dropdowns. If you renamed the entries as discussed in System Audio Settings section above then the target components will be easy to recognize by “Digirig” name, otherwise look for default “USB Audio Device” description.

If there is a choice of the channels, then set input to “Mono” and output to “Left”. Right output channel feeds into the internal VOX circuit (see next section).

For optimal results the input sensitivity and output audio levels will have to be later adjusted from their initial levels:

• Use the level slider in Digirig’s recording device (see System’s Audio Settings) to adjust the sensitivity of the received audio while monitoring the readout of the UV meter or the equivalent indicator in the software. The “listen” checkbox can be temporarily enabled in order to patch the received audio to the computer’s speakers and monitor the traffic on the air while fine tuning and troubleshooting the levels. Other factors playing into the received audio level is radio’s RF gain and value in Menu 08-11 DATA OUT LEVEL.
• Use the level slider in Digirig’s playback device (see System’s Audio Settings) to adjust the volume of the audio sent to the radio for transmission. Other factors playing into the received audio level is radio’s value in Menu 06-14 DATA DATA GAIN and any volume controls in the app (e.g. Pwr slider in WSJT-X).

PTT Settings

Most of the apps will try to get your data on the air. For that they’ll need to key up the radio. Digirig DR-891 supports multiple PTT options accommodating every application there is. Here are the choices in the order of preference starting from the most desirable:

• PTT by CAT – if the app supports CAT control then you want to take advantage of this capability for easy tuning into operating frequencies and may as well use it for PTT control. The radio will be keyed up by a command sent via the serial port. See next section for the setup information.
• PTT by GPIO3 (AKA RA Board) – Digirig’s sound card chip offers general purpose control lines. One of them (GPIO3) is wired to switch the hardware PTT line in the audio cable. Hard to imagine why this might be needed, but this method can be disabled by cutting the trace between the configuration pads labeled “GPIO” on the back of the PCB.
• PTT by RST or DTR – The RTS (ready to send) or DTR (data terminal ready) control signals FT-891’s COM port can be used to trigger PTT. This method has to be enabled in the radio’s Menu item “07-12 [PC KEYING]”. Select TRS or DTR accordingly. This will work with either Standard or Enhanced COM port number.
• PTT by tone or VOX – The audio sent to the right output channel of Digirig will key up the radio via the hardware PTT line in the audio cable. Although Digirig’s VOX implementation is highly optimized and is known to work great, consider it a fallback option for the cases when no explicit PTT methods are available such as in case of some apps on mobile platforms. If there is option to key up VOX by a tone it is more desirable compared to triggering VOX by the payload audio. All VOX circuits have inherent latency at the beginning and hang time at the end of the payload. Timing adjustments may be needed with the software settings mentioning “delay”, “prefix”, “preamble” or similar to offset this effect.

Serial CAT Settings

Your Yaesu FT-891 supports serial CAT control. It’s an optional feature, allowing the software running on the computer to control many features of your radio including VFOs, bands, filters, PTT etc. Previously using the CAT control required a separate USB cable to the computer which in many scenarios is undesirable. With DR-891 there are no longer any reasons to avoid the convenience of CAT where the software supports it.

In the rig control section of the software, you will have to specify:

• Transceiver command profile – select Yaesu FT-891
• COM port – select option associated with the Enhanced COM port in the Device Manager (See Devices earlier)
• Baud Rate – pick value matching your selection in transceiver’s Menu 05-06 CAT RATE. Set to 9600pbs if you picked the starter option (See Transceiver Settings earlier)
• Data Bits – 8, Stop Bits – 2 (1 also works)
• Flow control, handshake – disable all

Confirm successful CAT control by running a test and by using other features that utilize the rig control.

Using DR-891 With Other Radios

DR-891’s black audio socket is compatible with a wide selection of the standard Digirig audio/PTT cables. This allows the use of DR-891 as a functional equivalent of Digirig Lite when it comes to basic radios. You can use it with a range of transceivers HTs, mobiles and stationary radios to enjoy additional digital modes and operating opportunities.

⚠ Only audio/PTT cables with black molding on 3.5mm TRRS jack from other Digirig kits should be used in DR-891’s audio (black) socket. Connecting serial cables with green 3.5mm jack to DR-891’s colored USB socket may result in damage to the interface and/or the radio.

Notes Regarding RFI

If your setup works without any problems before the first transmission but becomes erratic during or after you send the power out, then the likely reason for the problem is radio frequency interference (RFI). The symptoms include radio getting stuck in transmission, serial port (rig control) errors, sound card errors. The effect may be different depending on bands, cables layout and seemingly other random factors.

RFI comes in two flavors:

• RF power from the antenna nearby wirelessly induces voltages in the radio’s accessory cables
• Unbalanced and insufficiently choked antenna uses radio’s accessory cables as part of the counterpoise system

To diagnose the issue, reduce the RF power to a minimum level (Menu 16-03 HF PWR) and ideally use a dummy load. If the problem goes away, then it is definitely related to the radio frequency interference. Another method is disconnecting the audio (MiniDin6) cable right before the transmit attempt and reconnecting it later. The software has no way of knowing if the audio cable is connected so if the previously present problem goes away in this scenario then it’s another clue that the feedback is happening via RFI.

The solution is to improve the antenna system, grounding and choking.

Other Troubleshooting

If you encounter any problems with setting up your Digirig DR-891 then try approaching your troubleshooting systematically. The different areas of the setup are mostly independent of each other and can be dealt with individually.

Follow the setup instructions in this manual in the order they are presented. Confirm that you are getting expected results before moving to the next section. Skimming the material is ok, but if you run into difficulties then focus on the area that gives you trouble and make sure you understand and follow every instruction. Do not change the defaults or deviate from the suggested values until after everything already works and you have a clear understanding of the effect of the modification. Reset radio or software to the defaults or to s last known good state if you changed too many things and can’t tell what causes an issue.

Technical Support

Please refer to the community forum for any technical support except for the cases pertaining to your specific Digirig order (warranty, returns etc.). Before posting your question, check out the existing threads. Powerful tagging and search options will help you narrow the results to the relevant discussions. Additional resources include the troubleshooting guide and Digirig’s Youtube channel. There are also numerous websites, forums and videos dedicated to Yaesu FT-891 which can be useful especially if your issue has to do more with the radio than DR-891.

When posting in the community forum please describe:

• your system including type of the computing device, OS, amateur radio software, antenna system and other accessories if relevant
• area of concern per the section headings above such as USB Devices, Audio Settings, CAT control etc.
• what troubleshooting steps you attempted and what results you got

Appendix

Digirig DR-891 Schematic