{"id":2258,"date":"2026-10-25T19:20:56","date_gmt":"2026-10-25T19:20:56","guid":{"rendered":"https:\/\/g1lro.uk\/?p=2258"},"modified":"2026-10-25T19:40:05","modified_gmt":"2026-10-25T19:40:05","slug":"new-in-the-g1lro-store-the-allscan-uri50-usb-radio-interface","status":"publish","type":"post","link":"https:\/\/g1lro.uk\/?p=2258","title":{"rendered":"New in the G1LRO store: the AllScan URI50 USB Radio Interface."},"content":{"rendered":"\n

New in the G1LRO store: the AllScan URI50 USB Radio Interface.<\/strong> It is the smallest, simplest and cheapest way we know to put a handheld radio on AllStarLink, EchoLink, APRS or the digital modes with genuinely good audio. If you have a K1-connector HT in a drawer and a Raspberry Pi doing nothing, you are about ten minutes away from a working node.<\/p>\n\n\n\n

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Buy the URI50<\/a><\/div>\n<\/div>\n\n\n\n
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The AllScan URI50 with the supplied cables<\/figcaption><\/figure>\n\n\n\n

What is the URI50?<\/h2>\n\n\n\n

The URI50 is a pocket-sized USB radio interface designed and built by David Gleason, NR9V, of AllScan in San Diego. David is also the author of the free and open-source AllScan web app for AllStarLink, so the hardware comes from someone who knows the software side intimately.<\/p>\n\n\n\n

AllScan describes it as an “AIOC++”. If you know the AIOC (All-In-One-Cable) or the DigiRig, the URI50 does the same job: it connects a handheld with a Kenwood-style K1 two-pin connector to a computer over USB, giving the computer audio in, audio out and PTT control. The URI50 then goes further in a few useful ways.<\/p>\n\n\n\n

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  • Proper sound card chip.<\/strong> It uses the C-Media CM108B, the USB audio controller that AllStarLink, Direwolf and most ham software already support natively, with 16-bit CD-quality converters and an internal mixer.<\/li>\n\n\n\n
  • Serious RFI filtering.<\/strong> Separate USB, digital and analogue ground planes and supply rails, ferrite beads and bypass capacitors on every I\/O line, and an RC filter on the analogue supply. This matters a great deal when the radio is transmitting a few centimetres from the interface.<\/li>\n\n\n\n
  • Works with low-cost HTs.<\/strong> Baofeng, Quansheng, Retevis, Radtel, TYT and the many other budget handhelds with a K1 socket all plug straight in.<\/li>\n\n\n\n
  • Serial UART as well as CM108 GPIO.<\/strong> PTT and COS can be handled through the CM108 or through a USB serial port, so it works with software that expects either approach. That covers practically every application on Linux, Windows and macOS.<\/li>\n\n\n\n
  • Status LEDs.<\/strong> USB host status (a heartbeat once the node software has the device), COS, PTT and ADC clip. When you are setting levels, the clip LED alone saves a lot of guesswork.<\/li>\n\n\n\n
  • Tiny.<\/strong> About 50 x 28 x 8 mm. Small enough to stick to the back of an HT.<\/li>\n<\/ul>\n\n\n\n

    What it works with<\/h2>\n\n\n\n

    Software:<\/strong> AllStarLink (ASL3), EchoLink, DVSwitch, Zello, APRS and Direwolf, DigiPi, Winlink and VARA, FreeDV, FT8, Fldigi and other packet and data modes.<\/p>\n\n\n\n

    Host computers:<\/strong> Raspberry Pi 3, 4 or 5, mini PCs such as the Dell Wyse 3040, or any Windows, Mac or Linux machine with a spare USB port.<\/p>\n\n\n\n

    Radios:<\/strong> any handheld with a K1 (Kenwood-style 2.5 mm and 3.5 mm) accessory socket. That includes many low-cost HTs such as the Baofeng UV-5R and its relatives, the Quansheng UV-K5 family, the Retevis RT85, and models from Radtel and TYT.<\/p>\n\n\n\n

    Built-in COS for clean ASL3 receive.<\/strong> Carrier-operated squelch detection is built into the board and enabled out of the box, just as on our red AIOC interface. With a suitable radio, this gives perfect receive operation on ASL3: the node passes audio only when the radio’s squelch is open, with no VOX timing to tune and no clipped first syllables. We have tested it on Baofeng and Quansheng handhelds, and many more models will work just as well.<\/p>\n\n\n\n

    How it works: on Baofeng, Quansheng, the Retevis RT85 and many similar radios, a DC bias appears on the speaker line only when the squelch is open on a signal carrying the correct CTCSS tone. The URI50 can use that bias as a carrier-operated squelch (COS) signal, so your node only passes audio for stations using your tone. To check a radio of your own, set the volume to around 20% and measure the DC on the 2.5 mm jack (tip to sleeve) while receiving a toned signal. If you see a steady 1 V or more for the whole time the squelch is open, it should work. COS on the ring of the 2.5 mm plug is also supported.<\/p>\n\n\n\n

    What’s in the box<\/h2>\n\n\n\n
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    • AllScan URI50 USB Radio Interface<\/li>\n\n\n\n
    • Short 2.5 mm TRS cable<\/li>\n\n\n\n
    • Short 3.5 mm TRS cable<\/li>\n\n\n\n
    • Short USB-A to USB-C cable<\/li>\n<\/ul>\n\n\n\n

      Everything you need to connect radio to computer. The cables are deliberately short, which keeps the build tidy and reduces RF pickup.<\/p>\n\n\n\n

      A note on ferrites:<\/strong> to keep postage weight down, we don’t include clip-on ferrites with the URI50. We do recommend fitting one to the USB cable, ideally with the cable passed through it once or twice. Any snap-on ferrite suited to VHF and UHF will do.<\/p>\n\n\n\n

      See it in action<\/h2>\n\n\n\n

      Freddy Mack, KD5FMU, the Ham Radio Crusader, unboxed the URI50 and had it running as an AllStar node within minutes, first with a Retevis RT85 and then with a standard Baofeng UV-5R on a Raspberry Pi running ASL3. Both produced clean, natural audio on the parrot test with only small tweaks to the radio’s volume knob.<\/p>\n\n\n\n

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