Author Topic: Filters  (Read 1828 times)


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« on: August 08, 2011, 11:12:01 PM »
110808-1423 EDT

Subject: Filters.

You do not define what is in each of your filters.

I conjecture the wall filter is a low pass multistage filter. Maybe something like a Corcom 5VR1. Little attenuation at 60 Hz, and starting to roll off somewhere above this. You also might have a notch at your carrier frequency, but unlikely. If a user were to go to some store to buy a filter for this purpose how would they know what to buy? What are the specs on your wall filter.

Your in-line filter is likely a tuned resonant circuit in series with the white wire. It would be tuned to your carrier frequency. Is that the case?

I suspect that your video on filters is next to useless to the average person. It does not describe the logic of the circuit and why this will do any good. Clearly a filter like the 5VR1 would not be optimum for use as the in-line filter.

The video moves too fast and does not make it clear exactly what is being done and how. The partial circuit shown is extremely short, no time to even focus, let alone study it.

The average person probably does not need to see two wires and a wire nut, and not see a bigger area showing how the filter is wired to other points. Way too fast.

This presentation would be far better as a slide show that could be paced by the viewer.

The important points relative to the in-line filter that are not clearly presented are:
1. A 120 V circuit is used as the wire pair for transmission of the signal from the MTU to the RDU or Gateway. This could be a circuit in the wall or an extension cord.
2. On this circuit there should be no noise generating loads. Preferably only the MTU, RDU, or Gateway should be on the circuit.
3. At the main panel the white wire of this circuit is removed from its circuit breaker.
4. The input wire of the in-line filter is connected to the breaker, and nothing else to that breaker.
5. The neutral wire of the filter is connected to the main panel neutral buss. Should be in an adjacent position to the neutral of above said circuit.
6. The output lead of the in-line filter connects to the white wire of the MTU, and the white wire (hot) of the above said circuit.

This in-line filter provides a high impedance to the MTU carrier frequency. The result is a reduction of loading on the MTU transmitter, and an attenuation of noise coming from the breaker side of the filter. This filter may not be a parallel resonant circuit but maybe a series inductance in the hot wire, and a shunt capacitor on the circuit breaker side from line to neutral.

What are the specs for the in-line filter?