Welcome to the FlexRadio Community! Please review the new Community Rules and other important new Community information on the Message Board.
Need the latest SmartSDR or 4O3A Genius Product Software?
SmartSDR v4.1.5 | SmartSDR v4.1.5 Release Notes
SmartSDR v3.10.15 | SmartSDR v3.10.15 Release Notes
The latest 4O3A Genius Product Software and Firmware
If you are having a problem, please refer to the product documentation or check the Help Center for known solutions.
Need technical support from FlexRadio? It's as simple as Creating a HelpDesk ticket.

ATU Rx attenuation on 80m?

Joe, KQ1Q
Joe, KQ1Q Member
edited September 2018 in SmartSDR for Windows
Flex 6300: if ATU is used on 80m with my g5rv (zs6bk variant), it tunes OK but apparently attenuates the receive level by one or two S units. This can also be seen as a lower S meter, lower audio level, and the waterfall display background getting darker. This is with AGC both on and off. Is this normal? Has anyone else see it?

This does not happen on 40m, 20m or 10m. However with this antenna the SWR there is typically below 1.5.

On 80m the measured SWR with my RigExpert AA-30 at 3,600 Khz is 3.4, which is expected for this antenna type. The ATU tune up says "success". 

I tried the same antenna back-to-back on 80m with my Kenwood TS-590S which can also have the ATU in-line with Rx, and there was no difference in received signal strength with the ATU in or out.

System details: Flex 6300 running SmartSDR 1.4.0.130
Flex operating mode: LAN remote
Windows 7 Home Edition SP1 64-bitMotherboard: EVGA P55 FTW (A72 BIOS)
CPU: quad-core Intel i7-875K @ 4.01Ghz, hyperthreading on, RAM: Corsair Vengeance 16GB DDR3 12800
System disk: 1TB Samsung 850 Evo SSD
Data disk: 4TB WD4000F9YZ 7200 RPM 
Video: EVGA nVidia GeForce GTX-660 2GB, driver: 348.88
Monitor: Dell U2412M, 1900x1200 resolution

Leave a Comment

Rich Text Editor. To edit a paragraph's style, hit tab to get to the paragraph menu. From there you will be able to pick one style. Nothing defaults to paragraph. An inline formatting menu will show up when you select text. Hit tab to get into that menu. Some elements, such as rich link embeds, images, loading indicators, and error messages may get inserted into the editor. You may navigate to these using the arrow keys inside of the editor and delete them with the delete or backspace key.

Comment As ...

Categories