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11 meter is very quiet?

I did an interesting experiment today just to see how much difference running a small amp actually makes on DX under real world conditions. I used my Anytone 5555n2 as the radio. Barefoot it peaks at 25 watts AM, 40 watts FM, and 60 watts SSB. I used a Palomar 200 amp. Running the radio at min power into the amp gives 120 watts peak on AM, 150 watts peak FM, and 160 watts peak SSB.
I logged into two different online SDR's, one in Utah and the other in Colorado. That's where the conditions were to at the time of the experiment.

Now for the fun part. I picked a clear frequency (I used 26.725) and went through each mode, first barefoot and then with the amp, first on one SDR and then on the other. I made careful notes of my results.

The results....... were somewhat surprising! On sideband, there was no perceptible difference in received strength between 60 watts and 160 watts. None. About S4 on both SDR's both barefoot and with the amp. The audio did sound slightly louder with higher power, but there was no difference in received strength.

On AM, barefoot there was no discernable signal at all! And just a wee trace of a signal down in the weeds with the amp on.

But on FM........with 40 watts barefoot there was zero signal received on one SDR and just a change in the tone of the static on the second. Switch to 150 watts FM with the amp on and there was a crystal clear signal on both SDR's!!! In fact it was almost full quieting on the Utah SDR.
For whatever reason the amp has a LOT more effect on FM vs. SSB.........which I suspect has to do with the constant peak power of FM vs. the transient peaks of SSB.

A fun experiment for sure, and those online SDR's are an amazing tool if you really want to see what you sound like at a distance. Good for adjusting audio, mic levels etc. too. Check 'em out!
 
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Just a note about using FM while checking signal strength differences, the AGC in an FM radio works somewhat differently than it does on AM/SSB. There are times when a small change can make a big difference. Example: I have a six element yagi for 6m. While monitoring a baby monitor up the road on 49.830 MHz, I can get a signal of S-9+30dB on the front but pretty much null it right out on the rear corner. This would normally indicate a FANTASTIC F/B ratio, which just is not possible with the configuration I have. This huge difference is due to the AGC function. I have proved this by monitoring the same signal when there was no sound and just a carrier from the baby monitor, and switching back and forth between AM and FM modes. Same signal, same radio, same antenna, same signal source and the difference was much more in FM mode than AM. Just some food for thought.
 
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it was jingles news crappy singing baby crying yesterday but flipped the opticom on and managed to get eastern alberta but every time he talked the kids would key up n drown him out.
then moved to another channel.sharp n loud was a guy in mass. as soon as we started to talk a full blood assjerk keyed up n mumbled pure bull sheet non stop. i turned volume down and turned my scanners up n listened to a car get away from him n 3 big fires
 
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i must ask but anybody seeing increased noise? aii my friends who talk local,50 mile radius are having a s 3 noise floor sometimes up to 5. we are in southwest mo, springfield- joplin area.
 
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Well, the power just got turned on to the new house next door this morning. And holy mama -- 9+Db RFI on 11M!! I'm going to have to get to the bottom of this very soon.
On the positive note; Last weekend, I finally got my Imax 2K back up (been down since hurricane Irma in 2017). So now I can werk DX on 10 and 11 again --- Hallelujah!

I'm hearing a few 11M stns out there trying, but none that can break-through this 9Db man-made "noise floor". But hey, it's great to be back on something other than a multiband loop for 10/11M!
BTW- 40M was open into Itlay BIGtime early (05:00UTC) this morning.
 
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GlocknSpiel said:
Well, the power just got turned on to the new house next door this morning. And holy mama -- 9+Db RFI on 11M!! I'm going to have to get to the bottom of this very soon.
On the positive note; Last weekend, I finally got my Imax 2K back up (been down since hurricane Irma in 2017). So now I can werk DX on 10 and 11 again --- Hallelujah!

I'm hearing a few 11M stns out there trying, but none that can break-through this 9Db man-made "noise floor". But hey, it's great to be back on something other than a multiband loop for 10/11M!
BTW- 40M was open into Itlay BIGtime early (05:00UTC) this morning.
Click to expand...
id be on that noise immedietly.longer you wait the more they will say is why did it take you so long to mention the problem
 
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