Powerline Interference?

Amazing what difference this Channel Master LTE Filter makes when you look at the spectrum.
 

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Wow, looks like a big out of band signal is swamping the front end of the receiver either saturating the front end amp or causing massive AGC.
Yeah. I found some strong signals in the 700MHz area. Unfortunately, my Televes DAT Boss UHF antenna seems to be an older design (RF 14-51) and the amp is directly connected to the driven element. My VHF is amped with a Televes T-Force single input preamp made for RF 14-36. I can connect the TinySA to each antenna line to see which is allowing in the most extra noise.
 
Yeah. I found some strong signals in the 700MHz area. Unfortunately, my Televes DAT Boss UHF antenna seems to be an older design (RF 14-51) and the amp is directly connected to the driven element. My VHF is amped with a Televes T-Force single input preamp made for RF 14-36. I can connect the TinySA to each antenna line to see which is allowing in the most extra noise.
My Dat Boss LR is also the old RF 14-51 model, thus the internal LTE filter starts up around 700MHZ. That's why I use the Channel Master LTE filter inline with it once I confirmed with CM that it was power-passing. It makes a big difference on keeping signals locked. The CM filter kills LTE completely flat-line, from what my spectrum analyzer said. Starting at 608Mhz, and just barely knicks my RF36 channel a little bit.

I'm using a UVSJ that's power-passing on both VHF and UHF, and I have a separate Televes 560383 preamp on the VHF antenna, which is a AC Y10-7-13 model.

I've made a lot of changes since this thread, but this was the work I did last Summer:

 
I did a little analysis on my antennas and UVSJ. My UVSJ is working well, but notice the Televes Datboss UHF needs no extra filtering of VHF band signals 50-250MHz.

My UVSJ helps tame a lot of UHF signals picked up by my Stellar Labs yagi.

I do need additional broadcast FM filtering for the Stellar Labs, so I have a VHF-Hi BPF on order.
 

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I did a little analysis on my antennas and UVSJ. My UVSJ is working well, but notice the Televes Datboss UHF needs no extra filtering of VHF band signals 50-250MHz.

My UVSJ helps tame a lot of UHF signals picked up by my Stellar Labs yagi.

I do need additional broadcast FM filtering for the Stellar Labs, so I have a VHF-Hi BPF on order.
 
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I was the very first person on Ebay to buy from Jan Jenca, and have bought 4-5 times from him. I also made posts at Avsforum and steered others to him. His stuff works, but they are quite pricey.

A easier way to go, is you can use a HLSJ (VHF-Lo/VHF-Hi & UHF band separator) to massively attenuate both FM and VHF-Lo signal. You just plug the antenna into the input, connect the Lo side to a terminating resistor then connect the Hi side to the rest of the system. In my tests this actually can attenuate FM much better than any FM trap I’ve tried. SEPARATOR / JOINER HIGH LOW VHF FREQUENCY OFF AIR JVI HLSJ 736902313442 | eBay

It does the exact same thing as the Jan Jenca bandpass filter, at 1/3 the price.
 
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I was the very first person on Ebay to buy from Jan Jenca, and have bought 4-5 times from him. I also made posts at Avsforum and steered others to him. His stuff works, but they are quite pricey.

A easier way to go, is you can use a HLSJ (VHF-Lo/VHF-Hi & UHF band separator) to massively attenuate both FM and VHF-Lo signal. You just plug the antenna into the input, connect the Lo side to a terminating resistor then connect the Hi side to the rest of the system. In my tests this actually can attenuate FM much better than any FM trap I’ve tried. SEPARATOR / JOINER HIGH LOW VHF FREQUENCY OFF AIR JVI HLSJ 736902313442 | eBay

It does the exact same thing as the Jan Jenca bandpass filter, at 1/3 the price.
Great thinking! I completely forgot about using a separator. I believe I will stick with JJ on this one if I am satisfied. The flatness and low loss is what sold me. Hopefully it performs as advertised. How weatherproof are the enclosures he uses?
 
I have an update to share. I actually bought a repack ready Datboss Mix, and the active element/preamp assembly snapped right into the older Datboss UHF model.

I added the Jan Jenca VHF-HI bandpass filter between my Stellar Labs yagi and preamp too. The results have been great thus far.

My main TV is a TCL Roku set, and I was able to find the hidden OTA menu to monitor signals. Here are screenshots of the menu...

My 2 edge full power signals are very strong with this 2 antenna array. Blows out my Channel Master CM-5020. My PBS is weak, but it is about 28 degrees off the main signal path. I may turn my VHF-HI yagi a bit toward it. Eventually, I plan to get this on my rotor and stabilize it with a pillow block support bearing, so I can watch other markets via tropo ducting and skip.
 

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Captain Midnight Yep, found that menu myself last year. It's fantastic with all the info they included! You don't even need an ATSC meter to aim your antenna, IF you use this. Of course, it's a little hard to be up 30' on a tower and use it, BUT, I've done it using my Android phone, and the Google Duo app running on my laptop.

Aim the antenna for best MER and BER on your WEAKEST channel, and the stronger ones will normally take care of themselves.
 
So..... where can we find the hidden OTA menu or maybe show us the keystrokes on the remote.
This is for a TCL Roku tv set. Not sure IF it works on all other manufacturers Roku tv sets:

"Roku hidden TV signal strength on OTA antenna channels". Make SURE you hear the "donk" noise on every button push. If not, it won't bring up the screen.

Press HOME button, and do the following button presses from the HOME screen:

Home, Home, Home, Home, Home, up, right, down, up, left, right on your remote. Do this fairly FAST
 
This is for a TCL Roku tv set. Not sure IF it works on all other manufacturers Roku tv sets:

"Roku hidden TV signal strength on OTA antenna channels". Make SURE you hear the "donk" noise on every button push. If not, it won't bring up the screen.

Press HOME button, and do the following button presses from the HOME screen:

Home, Home, Home, Home, Home, up, right, down, up, left, right on your remote. Do this fairly FAST
Roku needs a menu for their secret screens in the UI. I get tired of the remote cheat codes
 
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