Pixelation using an antenna & HDHR
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Mike88
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Is there any program that shows signal strength and/or signal quality when using WMC independent of which OTA tuner is used? I use AverMedia Duet cards & the only thing I have to go by is the WMC SS indicators showing anywhere from 1 to 6 bars. I'm having a problem with one channel & it would be nice to get a bit more info on what is happening.
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barnabas1969
- Posts: 5738
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dmagerl is correct that symbol quality is a measure of the number of blocks which could not be corrected... as I stated earlier.
He is completely wrong about signal quality. Signal quality is another name for Signal-to-Noise-Ratio, or SNR. SNR has nothing to do with a "bit stream". SNR is a purely analog measurement, as is signal strength/power. It has nothing to do with "bits" or any other digital reference.
Neither is a trade secret.
SNR (signal quality) is a measure of the relative amount of noise being received with respect to the carrier signal. The carrier signal is always a sine wave. If something is distorting this sine wave, then SNR is reduced. The distortion can come from many sources. Multipath is one of them, causing two or more carrier waves to be received out-of-phase. If the carrier wave is over-driving the input of the tuner and/or an amplifier which is placed between the antenna and the tuner... then the sine wave will be "clipped"... resulting in a waveform that is somewhere between a square wave and a sine wave. Typically, the "clipped" signal will also "bounce", causing harmonic distortion. This causes the SNR to suffer.
The first thing to try is to remove all amplifiers to see if that will correct the problem on channel 9. If it does, then you know you are over-driving the amplifier(s) and/or the tuner.
My advice is...
1) Do NOT feed the output of one amplifier (the OP calls this his "pre-amp") into the input of another amplifier. No more than one amplifier should be in the circuit between the antenna and the tuner.
2) After you follow advice #1, and you still have a problem on the strong channel, buy a filter which reduces the signal strength of the powerful channel. Insert this filter BEFORE the amplifier.
Pretty simple stuff. I'm not going to engage in a battle of wits with an unarmed person.
He is completely wrong about signal quality. Signal quality is another name for Signal-to-Noise-Ratio, or SNR. SNR has nothing to do with a "bit stream". SNR is a purely analog measurement, as is signal strength/power. It has nothing to do with "bits" or any other digital reference.
Neither is a trade secret.
SNR (signal quality) is a measure of the relative amount of noise being received with respect to the carrier signal. The carrier signal is always a sine wave. If something is distorting this sine wave, then SNR is reduced. The distortion can come from many sources. Multipath is one of them, causing two or more carrier waves to be received out-of-phase. If the carrier wave is over-driving the input of the tuner and/or an amplifier which is placed between the antenna and the tuner... then the sine wave will be "clipped"... resulting in a waveform that is somewhere between a square wave and a sine wave. Typically, the "clipped" signal will also "bounce", causing harmonic distortion. This causes the SNR to suffer.
The first thing to try is to remove all amplifiers to see if that will correct the problem on channel 9. If it does, then you know you are over-driving the amplifier(s) and/or the tuner.
My advice is...
1) Do NOT feed the output of one amplifier (the OP calls this his "pre-amp") into the input of another amplifier. No more than one amplifier should be in the circuit between the antenna and the tuner.
2) After you follow advice #1, and you still have a problem on the strong channel, buy a filter which reduces the signal strength of the powerful channel. Insert this filter BEFORE the amplifier.
Pretty simple stuff. I'm not going to engage in a battle of wits with an unarmed person.
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dmagerl
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On a digital bit stream, signal quality is much more than just SNR. Multipath, bit distortion, phase distortion, synchronization problems as well as noise all serve to degrade the signal and affect quality.
Bit Error Rate, BER is often used as a stand in to indicate signal quality and encompasses everything that can affect the signal. How the BER is converted to a number indicating quality is usually patented or held as a trade secret.
Bit Error Rate, BER is often used as a stand in to indicate signal quality and encompasses everything that can affect the signal. How the BER is converted to a number indicating quality is usually patented or held as a trade secret.
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barnabas1969
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The measure of signal quality on these tuners is purely an analog measurement. Digital TV signals, both OTA and cable, are only digital after the signal is demodulated. The radio signal itself is analog.