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Firmware · 2022-06-29

Uniden SDS100 firmware 1.21.00 main / 1.02.01 sub

Verified — manufacturer file

Download zip (2.1 MB) Manufacturer's page ↗

Main firmware 1.21.00 (29 June 2022) with sub firmware 1.02.01 (7 March 2019), as Uniden packaged them for a manual install. 1.21.00 added 2.5 kHz and 3.125 kHz steps to Custom Search and Discovery and was a "housekeeping update to accommodate revised hardware". It is the last release before Waterfall support.

Read before installing. Manual-install package posted by Uniden in January 2024 for owners who want to return to pre-Waterfall firmware. Main and sub must be downgraded together. Waterfall does not work on this version; a purchased Waterfall key stays stored in the scanner. The files inside are dated 29 December 2023; whether they are byte-identical to the 2022 Sentinel-delivered release could not be confirmed.
Product
SDS100 firmware
Version
1.21.00 main / 1.02.01 sub
Released
2022-06-29
Runs on
Any PC that can copy files to a USB mass-storage device (Uniden's steps use Windows Explorer)
Applies to
Uniden SDS100
Zip SHA-256
4ee1f919a22b9f004de81bef7ace1b7c611fc9d7b2233a5a0388d71d4e1da904

Contents

FileSizeSHA-256
SDS100 V1.21.00 Main V1.02.01 Sub.zip2.1 MBd9d2e014759a5c55a2cfe5a2e441ac2065a79331d0d6cfbede188e4e46804d57
README.txtThese instructions
SHA256SUMSChecksums of the files above

Instructions

The complete README.txt included in the zip:

Uniden SDS100 firmware 1.21.00 main / 1.02.01 sub
=================================================

WHAT THIS IS
Main firmware 1.21.00 (29 June 2022) with sub firmware 1.02.01 (7 March 2019),
as Uniden packaged them for a manual install. 1.21.00 added 2.5 kHz and 3.125
kHz steps to Custom Search and Discovery and was a "housekeeping update to
accommodate revised hardware". It is the last release before Waterfall
support.

IMPORTANT: Manual-install package posted by Uniden in January 2024 for owners
who want to return to pre-Waterfall firmware. Main and sub must be downgraded
together. Waterfall does not work on this version; a purchased Waterfall key
stays stored in the scanner. The files inside are dated 29 December 2023;
whether they are byte-identical to the 2022 Sentinel-delivered release could
not be confirmed.

Uniden normally delivers firmware only through Sentinel (UPDATE -> Update
Firmware), which always installs the newest version. Uniden published this
package on its change-log page so that owners can install this specific
version by hand - in practice, to go back to it. To bring a scanner up to
date, use Sentinel instead.

APPLIES TO
The Uniden SDS100 (US model) only. Every firmware file carries the model name
(SDS-100_...). Do not use it on the SDS200, SDS150, BCD436HP or BCD536HP. The
European SDS100E uses separately named firmware files (e.g.
SDS100E_V1_23_09.bin, per RadioReference owners) and must not be given these
files.

BEFORE STARTING
  - A Windows PC. Uniden's instructions use Windows Explorer; the scanner
    appears as an ordinary removable disk.
  - The mini-USB data cable, in the mini-USB port on the side of the scanner
    (the one marked Charge, not the micro-USB port).
  - A fully charged battery (Uniden's readme asks for this), or the scanner on
    USB charge.
  - A backup: copy the whole microSD card to the PC and save the Favorites
    Lists in Sentinel first (Uniden's readme asks for both).

CONTENTS OF THIS ZIP
The download zip holds the vendor file exactly as Uniden published it, plus
this README.txt and SHA256SUMS.

  SDS100 V1.21.00 Main V1.02.01 Sub.zip  (2220967 bytes)
    SHA-256 d9d2e014759a5c55a2cfe5a2e441ac2065a79331d0d6cfbede188e4e46804d57

  Inside SDS100 V1.21.00 Main V1.02.01 Sub.zip:
    Readme SDS100 V1_21_00.txt
      Uniden's own instructions (downgrade to 1.21.00)
      2563 bytes
      SHA-256 2717eeae3690a1bcae7bb65ad81769e78f455b1974146926a04f466b7f7421da
    SDS-100_V1_21_00.bin
      main (CPU) firmware 1.21.00
      2162688 bytes
      SHA-256 1a33ef31388d922c88f14bfefe82a43d8d759006ea8e87f0241d82e795a14085
    SDS-100-SUB_V1_02_01.firm
      sub-processor firmware 1.02.01
      82992 bytes
      SHA-256 aedd8ae74617a778a663ea4a1123c827c915065f53a290fc7e06f0b6c0171125

INSTALLATION
  1. Turn the scanner on.
  2. Connect it to the PC with the USB cable. The scanner shows "USB Cable
     Detected / Select USB mode" with "Mass Storage = E" and "Serial Port =
     .".
  3. Press E (Yes) to choose Mass Storage. The scanner shows "USB Mass
     Storage".
  4. In Windows Explorer, open the new removable disk, then the "BCDx36HP"
     folder, then its "firmware" folder. It already holds CitiTable_V00_00.dat
     and ZipTable_V00_00.dat - do not touch or delete them.
  5. Unzip the download on the PC and copy SDS-100_V1_21_00.bin and
     SDS-100-SUB_V1_02_01.firm into the "firmware" folder. Only one main
     (.bin) and one sub (.firm) file may be in the folder at a time; with
     several versions present the update will not start or will load
     incorrectly.
  6. Restart the scanner ("reset the power", in Uniden's words). The update
     starts automatically as it boots. Do not turn the scanner off until the
     update has finished.
  7. When it has finished, the scanner deletes the firmware file(s) from the
     "firmware" folder by itself.

VERIFYING
Menu -> Settings -> See Scanner Information -> Firmware Version shows the main
and sub versions now installed. The firmware file(s) will also have gone from
the card's "firmware" folder.

IF SOMETHING GOES WRONG
  - Update did not start: check that only one main and one sub file are in the
    "firmware" folder and that the file names are exactly as supplied.
  - Scanner will not start properly after files were deleted from the
    "firmware" folder: the two .dat files were probably removed. Uniden's
    remedy is Sentinel -> Clear User Data, which rebuilds the card but erases
    all user data (hence the backup).
  - USB connection fails or is slow: take the microSD card out and use a card
    reader; Sentinel can work on the card directly (see Vol 5 on this site).
    The same folder layout applies.
  - Card errors: back up what is readable, format the card with the SD
    Association's SD Memory Card Formatter (cards up to 32 GB), run Sentinel
    -> Clear User Data, then Update Firmware.
  - Uniden does not document a recovery procedure for an update interrupted by
    power loss; this could not be confirmed from any source. Uniden's readme
    closes with "Please use these files on your risk."

DOWNGRADING
This package exists for going back: Uniden's readme covers moving from any
later version. Main and sub must be changed together. To return to the current
version afterwards, run Sentinel -> UPDATE -> Update Firmware.

Waterfall stops working on 1.21.00; a purchased Waterfall key stays in the
scanner and works again after updating to current firmware.

PROVENANCE
  - Official source:
    https://info.uniden.com/twiki/pub/UnidenMan4/SDS100FirmwareUpdate/SDS100%20V1.21.00%20Main%20V1.02.01%20Sub.zip
  - Listed on:
    https://info.uniden.com/twiki/bin/view/UnidenMan4/SDS100FirmwareUpdate
  - Wayback copy:
    https://web.archive.org/web/20260101204703/https://info.uniden.com/twiki/pub/UnidenMan4/SDS100FirmwareUpdate/SDS100%20V1.21.00%20Main%20V1.02.01%20Sub.zip
  - Retrieved: 2026-09-18. Status: verified (downloaded from Uniden's own
    server; SHA-1 matches the Wayback capture).

MORE INFORMATION
  - scanners.fubsypoly.com, Uniden SDS100 - Vol 5, Upgrades & Firmware:
    https://scanners.fubsypoly.com/uniden-sds100/vol-5/
  - Reference Library, SDS100 Owner's Manual:
    https://scanners.fubsypoly.com/library/uniden-sds100-original-manual/
  - Reference Library, Easier to Read SDS100/SDS200 Manual:
    https://scanners.fubsypoly.com/library/easier-to-read-sds100-200-manual/
  - Uniden change log:
    https://info.uniden.com/twiki/bin/view/UnidenMan4/SDS100FirmwareUpdate

Other versions of SDS100 firmware

← All Uniden SDS100 downloads