SCU Noise Mitigation, ?????

Robert Lonn

The SCU enables listening to multiple bands at the same time on the same antenna. A hardware platform with multiple SCUs such as the FLEX-6600M allows for monitoring multiple bands on different antennas or the ability to perform more complex noise mitigation techniques that are available in multi-antenna systems.

Has Anyone tried to do this and if Yes, How???

KP2L

Yes , there is one available called diversity reception in Smart SDR.  It is explained quite well in the software manual. It's not really a noise mitigation technique as it is a weak signal enhancing technique.

Robert Lonn

WELL!!!!! It took me a bit to find it in the manual! So for others, this is my takeaway!!

First, the information, Diversity Reception, on this is on page 86 of the 2.3.9 manual.  Older Manuals around page 73.. This only works with the 6600M Dual Receiver units. I had Antenna A on my large Carolina Windom antenna, my arsenal of receive only antennas are connected to RXA input..

You need to use Stereo Headphones, and turn off the front speaker on the "M" version!  I found that you can increase the RF gain a lot when in this mode trying to dig out weak signals. Also the AGC-T can be adjusted as well for optimum reception.. The results were Amazing!! Being able to turn on and off DIV reception allows you to hear the station in a normal fashion or with Dual Antennas and DIV reception..

I dug around the band for some very weak signals on 20 meters tonight, and the ability to do this was the difference from a station NOT being heard, and Being Heard with reasonable good clarity!!! I could switch the RXA side to several long wire antennas, LOOPS, V's, and when you select the correct antenna, well the magic of the Flex goes to work!!!

If you have multiple antennas and have not tried this, you should!!!!

Robert
WA6PHN

KP2L

Well no doubt that two receivers hooked to two different antennas can produce interesting results.  But the magic happens between your ears!!

All the more reason to buy a flex that has two spectral capture units.  And as we all know the current solar cycle conditions makes pulling out the weak ones more challenging.


Carl KP2L

W4TMW

Robert, how do you have your receiving wires configured, as long wires or Beverages? I've installed a 250' (rx only) wire about 10' off the ground and will connect a 9:1 Unun on the Rx'er end and far-end will be open ( no resistor at this time). I will be installing some ground radials on the ground below the Unun ( no ground rod at this time). The wire is positioned perpendicular to an OCFD at 50' and 100' from it. For the higher bands I'll be using it with my Hex Beam at 60'. Considering what I've written here, do you have any add'l suggestions? Flex 6600 here.   Tom W4TMW

Robert Lonn

It is very Hit and Miss when it comes to using Diversity Reception.. This morning I found the MFJ Loop did better then my 60 foot longwire antenna, exact opposite from what I experienced last night..  My Primary antenna is my Carolina Windom antenna, then I select from several other Long wire antennas, V antennas, Loops, etc.  for the "B" receiver.  One Long wire runs North-South, the other runs East-West.. I switch these remotely from a  Ameritron 1X4 remote switch. 

Signals arrive several different ways, Sky Wave, Ground-Wave, Ducting where the signal arrives Short and Long Path at the same time.. All of this along with antenna selection will determine what you hear in the headphones, and how the brain interprets this... 

As stated, last night with one antenna, could not make out what the ZL was saying, but with Diversity turned on his S-3 to 4 signal became readable.. Very Impressive..

Robert

W4TMW

Thanks for the add'l info Robert, sounds like you have a nice crop of antennas there

I'm really looking forward to trying out this system. One of the main reasons I moved up to the 6600. I'm hoping it will come in handy especially with the poor propagation on the lower bands.  73, Tom