DSDPlus is a Windows application capable of reliably decoding multiple types of digital audio formats commonly found on VHF, UHF and 800 MHz, including (but not necessarily limited to):

P25 Phase 1 / Phase II (including TDMA control channels)
ProVoice EDACS Digital voice
X2-TDMA - Motorola public safety TDMA system with P25 style signaling (mostly based on DMR)
DMR/MOTOTRBO - DMR conventional, Tier II, Tier III Standard (Hytera, Tait, etc) and Tier III non-Standard (Motorola Capacity Max and Selex/Leonardo)
NXDN - 9600 baud (12.5 kHz) NEXEDGE and 4800 baud (6.25 kHz) NEXEDGE/IDAS - both trunked and conventional
D-STAR
Yaesu Fusion

DSDPlus can be used with external signal sources such as an SDR (E.g RTLSDR v3/v4, Airspy M2, etc) or a discriminator-tapped receiver. To learn how to set this up, read the included Notes.txt and DSDPlus.txt files.

DSD+ Public Version 2.547

The latest public release version of the popular digital decoder software is V 2.547. This is the first public release since V 1.101 and includes many new features previously only available to Fast Lane members. Changes include the introduction of FMP24, FMPP, and FMPA, and the software no longer requires the use of virtual audio cable routing to external audio sources like SDR#.

The Public version of the software and updates to the software can be found at the DSDPlus website. Once downloaded, you can automatically keep the program updated by clicking the *Misc* tab in the 1R Event Log, then checking the option "Automatically check for updates". You can also just disable the option and check for updates manually through the same menu.

The creator asks that any bugs be reported on the Voice Control Channel Decoding Software Forum.

The Fastlane program

The Fastlane program was a way for an individual to receive early access to features for bug-testing purposes and to support the Developer/s. The program will continue to be active for old members and new features will continue to be released. However, no new memberships are being accepted at this time (As of December 2025).

DSD+ Features:

Supports single-receiver mode via FMP24, FMPA, or FMPP (Fast Multi-Protocol receiver), reducing the need for multiple dongles - Actively jumping from the control channel to the voice channel and back.

When two SDR receivers are available, you can dedicate one to a trunked control channel while the other will dance around the voice channels. This is useful if you want to prioritize voice call traffic so that you never miss a call from your favorite talkgroups.

Scanlist - to monitor analog and digital non-trunked conventional frequencies, sweeping through a variety of frequencies that you add to the DSD.Scanlist file, working as a standard scanner.

Ability to save audio output from digital audio formats in both .WAV and .MP3 format.

And so much more! Please read the changelog portion in the Notes.txt file within your dsd+ directory for full details.

Update Information:

There's been many changes to DSD+ since its last public release - too many to go over, but here's some notable changes from DSD+ 1.101 to DSD+ 2.547.

For a full list of changes and details over the years, read the Notes.txt file included within the latest DSD+ Release.

Version	Date (approx.)	Component	Key Changes
2.547	Dec 2025	DSD+ / Latest Public Release	Full public release of Fast Lane features: P25 Phase II trunking/voice decoding, neighbor auto-roaming, talker alias server integration, site loader, single-receiver mode, encrypted voice following (AlgID/KID only), TIII std/non-std handling, raw P25 packet data window, direct/TCP linking, automatic updates, and more. Includes FMP24/FMPA/FMPP for SDR support (no virtual audio cables needed). Phasing out v1.101. Read Notes.txt for installation and full capabilities.
Various	2025	FMP24 / FMPA / FMPP	Updated for new public release; supports RTL-SDR v4, RSP1A fixes, bias-tee, and UTF-8 checks in freq files.
1.112	2016	DSD+	Per-call MP3 recording (-Pmp3); DCDM (Dual Capacity Direct Mode) decoding; D-Star voice synthesis; improved Cap+ & RAS
1.114	2016	DSD+ / FMPA / FMP24	Raw source audio monitoring modes 0–4 (-m<num>); FMP24 2.4 Msps released
2.5	2016	DSD+ / FMP24 / FMPA	P25 simulcast PSK support (auto-center tuning, no FM demod); P25 Phase I trunking; NEXEDGE composite CC
2.8	2016	DSD+	Cap+ frequency lookup by tuned freq for future trunking support
2.10	2016	DSD+ / FMP24 / FMPA	FCC CSV license integration; control/rest channel following; NEXEDGE single-channel sites; -F<num> multi-instance support
2.18	2016	DSD+ / FMP24	NEXEDGE96 composite CC; window resizing & text scaling; DSDPlus.bin config storage
2.29	2016-12	DSD+ / FMP24 / FMPA / LRRP	Con+ frequency file auto-decoding; NXDN & NEXEDGE AVL → LRRP; audio shaping filters; eye pattern display
2.32	2017	DSD+ / FMP24	Critical bug fixes; scanner bandwidth locking (-b-)
2.39	2017	DSD+	Capacity Max support; Cap+/Con+/TIII enhancements
2.71	2017	DSD+ / FMP24 / FMPA / LRRP	Fusion & D-Star full support + per-call recording; encrypted voice priority control; conventional priority control; signal-type tags (CS/CB etc.)
2.84	2018	DSD+	Pseudo network IDs & NID prefixes for conventional/TIII/iDAS; memory/threading improvements
2.98	2018-03	DSD+	Better D-Star/Fusion/NXDN; TIII & neighbor improvements
2.113	2018-06	DSD+ / FMPA / FMP24 / LRRP	Memory reduction; D-Star DTMF; synthesized volume control; bearing display from CSV
2.145	2018	DSD+ / FMPA / FMP24	P25 Phase II trunking & voice decoding (requires VC RTL/Airspy + TCP)
2.155	2018	DSD+	TIII & NEXEDGE DFA support; resolved polarity & .P25data issues
2.165	2018	DSD+	TIII CPS-P3 numbering plan support
2.169	2018	DSD+	Additional TIII messages
2.176	2018	DSD+ / FMP24 / FMPA / FMPP	Single-receiver mode (-r1) with TCP/remote support; hide below-threshold traffic
2.183	2018	DSD+	Single-receiver Cap+ & TIII tracking; per-call alias in filenames
2.186	2018	DSD+	Manual update check (U key)
2.197	2018	DSD+ / FMP24 / FMPA / FMPP	Site loader window + conventional tuning; bias-tee support
2.205	2018	DSD+	Multiple DMR talker alias formats; “new talkgroup high priority” mode
2.212	2018	DSD+	Improved site loader; reduced .radios writes
2.228	2018	DSD+	EP/DES/AES differentiation for encrypted DMR
2.235	2018	DSD+	Amateur-radio settings; various cleanups
2.242	2018	DSD+	Bug fixes; trunking site auto-load at startup (-F<num>)
2.245	2018	DSD+	Stability; P25 neighbor fixes
2.254	2018	DSD+	Current/Seen Groups & Radios windows; TDMA tagging
2.256	2018	DSD+	Reduced CPU usage for windows
2.268	2018	DSD+ / FMP24 / FMPA / FMPP	Direct connection mode (-i<linkID> / -o<linkID>); integrity checks; menu download base files
2.275	2018	DSD+	Critical date-handling bug fix
2.289	2019	DSD+	Limited-info P25 systems; ProVoice simplex sync
2.296	2019	DSD+	More call-start alerting options
2.303	2019	DSD+	Fixed per-call audio saving; DMR UDT NMEA
2.324	2019	DSD+	DMR DCC disambiguation in .frequencies; flashing talkgroup hold
2.345	2019	DSD+	P25 TDMA control channel decoding (untested voice following)
2.347	2019	DSD+	P25 TDMA CC updates
2.357	2019	DSD+	Adjustable CC hunt dwell; P25 TDMA CC tracking (untested)
2.360	2019	DSD+	Faster data file loading; iDAS CC hunt timer
2.368	2019	DSD+	Limited encrypted voice following (collects AlgID/KID only)
2.383	2020	DSD+	Reduced memory; more DMR AVL; neighbor duplicate handling
2.390	2020	DSD+	Better encrypted voice following & KID display
2.395	2020	DSD+	Fixed per-call audio saving; encrypted P25 TDMA AlgID/KID display
2.441	2020	DSD+	TIII broadcast talkgroup calls; Harris P25 talker alias (Ph II); raw P25 packet data window
2.443	2020	DSD+	Bug fixes from 2.441
2.444	2020	DSD+	Console log fixes; base files integrity checks
2.448	2020	DSD+	UTF-8 space checks in data files
2.457	2020	DSD+	Complete TIII rewrite (Std vs nonStd, areas, network models, prefixes); major .networks/.sites/.frequencies changes required
2.464	2020	DSD+	Inbound P25 CC decoding; tune-to-input menu; removed Scroll-of-Death
2.465	2020	DSD+	Fixed dual-receiver TIII; inbound P25 CC menu toggle
2.505	2021	DSD+	Harris & Motorola scrambled talker alias via server; OTA alias priority limits; HighPPMerr display
2.506	2021	DSD+	Quick tweaks & bug fixes
2.509	2021	DSD+	Per-radio alias priority OTA attempt limit menu
2.516	2021	DSD+	Major talker-alias overhaul: discards old .radios Motorola aliases → reacquires via server; server shares aliases; simplified Motorola algorithm; neighbor-list roaming (P25 & DFA); removed -t -T -E params
2.520	2021	DSD+	Internal talker alias handling changes
2.522	2021	DSD+	Stability improvements; backup reminder
2.523	2021	DSD+ FL	Additional stability improvements
Various	2017-2024	FMP24 / FMPA / FMPP / LRRP	Numerous tuner-specific fixes (RSP1A, v4 dongles, API updates, UTF-8 checks, bias-tee, etc.)

**Event Log Features**
FORMAT	Voice	CC-Decode	Radio ID	Talkgroup	Access Code	Time-Slot	GPS Data
DMR	YES	YES	YES	YES	CC	YES	YES
D-STAR	NO
IDAS	YES	NO	YES	YES	RAN	N/A
NXDN	YES	YES	YES	YES	RAN	N/A
P25	YES		YES	YES	NAC	N/A
ProVoice	YES		YES	YES
X2-TDMA	YES					YES

NOTE: This application does not support any type of decryption.

The forum for discussion of this package can be found here.

Excellent write-up on setting up DSD to work with a RTL-SDR/discriminator tap for Trunking purposes
[ Software Screenshots - Coming soon]
ReadMe

DSDPlus.exe Rev 1.023 Info
SHA256: e6023701f0b02d6f356ad7c5b5ed19cb6dc9065a2cb3ab509a7508da93f4750f
MD5: 1f926b25c4385422eb409f6b69170a9d

DSDPlus

From The RadioReference Wiki

Contents

DSD+ Public Version 2.547

The Fastlane program

DSD+ Features:

Update Information:

Related Links