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About one year later, I have been struggling with real channel 7 (ABC channel 25 Virtual).
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RF 9 always solid and not intermittent.
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mild pixilation on rf 7 with no reception on the Antennacraft. Again rf 9 receivable on both antennas.
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This gremlin is on my last nerve!!
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Your gremlin is FM second harmonic interference that harms 7 more than 9.
http://www.tvtechnology.com/digital-...ference/202503
CH 7, 174-180 MHz, 1/2 = 87-90, WVJC 89.1 +4.2 dBm
CH 9, 186-192 MHz, 1/2 = 93-96, WYNG 94.9 -9.2 dBm, 13.4 dB less
see Attachment
Possible solution: two HLSJ in series between antenna and preamp
Ant > HLSJ > HLSJ > AD Juice Preamp > coax down > Power Injector > TV
http://www.hollandelectronics.com/ca...-Diplexers.pdf
The Juice preamp doesn't have an FM filter, but it is highly resistant to overload.
Is it safe for me to assume that your coax shield is grounded with a grounding block to help reject interference?
It is also possible that the noise level on VHF from electrical interference is high at your location. I have a VHF-High channel that would seem to be strong enough, but the noise level is so high the SNR for that channel barely makes it to 15 dB as shown on the Diagnostics Screen of my Sony TV. Sometimes I can receive that channel, sometimes not according to how high the noise level is at that time. I have been able to measure the strength of that signal and the noise level of the vacant adjacent channel with my old Sadelco 719E signal level meter (SLM) to confirm that. I have also used my Sadelco DisplayMax 800 SLM to make similar measurements of SNR.
OTA signals are constantly changing in strength, especially for 1Edge and 2Edge signals that are less stable than LOS signals. This is why you need to have a fade margin of at least 10 dB for your NM after adding antenna and preamp gains.