SmartSDR v3.9.19 and the SmartSDR v3.9.19 Release Notes
SmartSDR v2.12.1 and the SmartSDR v2.12.1 Release Notes
The latest 4O3A Genius Product Software and Firmware
Need technical support from FlexRadio? It's as simple as Creating a HelpDesk ticket.
FT8 Optimal Transmission Compression Level

I have a 6600 and I use JTDX for FT8/FT4, what are the ideal transmission Compression Level for a good clean quality output signal ?
If I understand correctly that will be done by adjusting:
RF Power on the SmartSDR.
TX Gain on SmartSDR DAX.
PWR on the JTDX (upper right corner vertical lever).
Thanks.
Comments
-
Using WSJT-X, not JTDX, guess they work about the same. This is my levels, seem to be working for me. Done some 41K contacts in FT4/FT8. No complaints so far, maybe will be coming now 😁
1 -
Hello Johan and thank you, yes I guess either WSJT-X and JTDX are about the same. Trying to be a good neighbor and operator, still learning, want to get a good clean quality signal, as I seen some nasty ones. So far I had been trying to keep my TX solid indicator line right a the -10 mark followed to about maybe a -5 with the individual square (not sure which is the correct to read).
0 -
As long as your level 'square' is not showing red, your signal should be clean. . In digital modes, processsing and compression is disabled.
AL, K0VM
1 -
Thanks Al, yes I always wonder the correct reading (Level) if the solid line or the individual square (to given them some names).
0 -
I have found use DIGIU mode in radio (in radio tab of WSJT-X set mode to Pkt/digi-u.). This disables any compression or TX EQ.
set DAX TX level to 48 and power slider in WSJT-X all the way up. The TX Level indicator on radio level meter should peak right near zero and be yellow, not red. Adjust desired power out using RF power on radio.
Dave wo2x
1 -
Thanks David, yes I also use DIGIU on my 6600, JTDX PWR to the top or sometimes I'll bring it down a notch or two (-0.3 or -0.6) then my TX Gain on SmartSDR DAX to around 40-43 trying to be in yellow well before 0 more likely to around -5 in Level.
0 -
You should see no difference in signal purity from TX level just reaching zer and staying yellow to running it around -5 as far as FT8 tones.
73
Dave wo2x
1 -
OK I thought there will be a difference in that range -10 to 0 as far as the output quality, thanks.
0
Categories
- All Categories
- 335 Community Topics
- 2.1K New Ideas
- 602 The Flea Market
- 7.9K Software
- 6.2K SmartSDR for Windows
- 169 SmartSDR for Maestro and M models
- 400 SmartSDR for Mac
- 263 SmartSDR for iOS
- 247 SmartSDR CAT
- 184 DAX
- 371 SmartSDR API
- 9.1K Radios and Accessories
- 17 Aurora
- 176 FLEX-8000 Signature Series
- 7.1K FLEX-6000 Signature Series
- 912 Maestro
- 52 FlexControl
- 857 FLEX Series (Legacy) Radios
- 881 Genius Products
- 447 Power Genius XL Amplifier
- 318 Tuner Genius XL
- 116 Antenna Genius
- 279 Shack Infrastructure
- 196 Networking
- 441 Remote Operation (SmartLink)
- 137 Contesting
- 735 Peripherals & Station Integration
- 137 Amateur Radio Interests
- 950 Third-Party Software