SSB noise from solar panels

[Cadence]

Originally Posted by transmitterdan

The solar panel does not make “RFI”. The charge controller makes all the noise.

I would have to agree with you. I can't imagine the cells making RF on there own.

[continuouswave]

Originally Posted by transmitterdan

The solar panel does not make “RFI”. The charge controller makes all the noise.

As mentioned in the cited article, some photo-voltaic generating panels have imbedded voltage convertors. The article will explain the problem and the methods used to suppress RFI from the photo-voltaic panels.

Even with panels that do not contain embedded voltage convertors, the photo-voltaic panels are connected to the charge controller, and all the wiring related to the panels becomes part of the radiating system of the RFI. In order to suppress radiation of the interference, the panels had to be included in the system of filtering and suppression of RFI.

The article is quite a good treatment of the problem. The author and several other volunteers, including the vendor that installed the system, worked together and diligently to suppress the RFI being created. It was not a simple or easy cure. The author is a long-time radio amateur and has an engineering background. You might want to read it. I found it very interesting, but also somewhat discouraging; if home electrical generation from photo-voltaic panels becomes more common, the HF spectrum will be rendered useless for any sort of weak signal work by RFI from unfiltered, unshielded, and unsuppressed installations.

[Cadence]

How else would it be done?

much reduced RFI output by use of filtering, chokes, grounding, and shielding.

[Viking Sailor]

CW,



That's great!


How about a link to the article.


Otherwise your assertions are mute.

[TreblePlink]

I've dealt with quieting RFI from switching power supplies (essentially charging controllers) many times.

The controllers turn the panel's DC into square-wave AC. A sine wave AC does not contain harmonics, (multiples of the pwm switching frequencies) while a square wave is rich with them.

These harmonics reach radio receivers either through the enclosure on a poor design, but commonly is radiated by the input and more often the output wires.

Placing a Low-pass-filter between the output of the controller and the batteries or loads usually cures it. If somebody wants to do a DIY I would be happy to provide component values.

https://en.wikipedia.org/wiki/Low-pass_filter

[Cadence]

Sometimes a little bit of knowledge is dangerous.

[transmitterdan]

If it has a voltage converter embedded in the panel it isn’t just a solar panel. Do any panels used on boats contain internal voltage converters? If so, which ones?

[jhe]

Thanks very much for all the responses. I think I will install a switch at the navy station to turn off the input from the solar panels. I have to turn off inverters and refrigerators as well. One more thing. I’m not going to leave the SSB running for long so that s ok for me.

[continuouswave]

Originally Posted by Viking Sailor

...How about a link to the article[?]

I believe you have to join the American Radio Relay League to read their journal.

Originally Posted by Viking Sailor

...Otherwise your assertions are mute.

Why are you so aggressive?

[conachair]

Originally Posted by jhe

Thanks very much for all the responses. I think I will install a switch at the navy station to turn off the input from the solar panels. I have to turn off inverters and refrigerators as well. One more thing. I’m not going to leave the SSB running for long so that s ok for me.

Tried asking Victron? They seem keen to help.

https://www.victronenergy.com/live/

[continuouswave]

Originally Posted by jhe

Thanks very much for all the responses. I think I will install a switch at the [nav] station to turn off the input from the solar panels. I have to turn off inverters and refrigerators as well.

Since you have already identified the source of the noise and you have control over those sources, shutting those devices off when you want to have low-noise HF reception is the simplest solution.

Reducing locally generated noise input into an HF antenna can be quite tricky. The topic is a complicated one. Since you're on a boat, discussion of grounding becomes somewhat vague--particularly if the boat has a fiberglas hull. Your HF antenna is probably end-fed against a ground or counterpoise, and that tends to increase its susceptibility for noise pick-up. And the antenna and the solar panel are probably not very far apart, further increasing the noise pick-up.

I think substantial reduction of the locally generated noise is going to take more than clicking on a link to a Wikipedia article about low-pass filters.

The one thing working in your favor: when you are at sea and miles from another other noise sources, if you shut off your local noise generating devices you should then be in a very quiet and RFI free environment.

[Cadence]

Originally Posted by jhe

Thanks very much for all the responses. I think I will install a switch at the navy station to turn off the input from the solar panels. I have to turn off inverters and refrigerators as well. One more thing. I’m not going to leave the SSB running for long so that s ok for me.

Good decision!

[Viking Sailor]

Originally Posted by continuouswave

Quote:
Originally Posted by Viking Sailor
...How about a link to the article[?]

I believe you have to join the American Radio Relay League to read their journal.

Quote:
Originally Posted by Viking Sailor
...Otherwise your assertions are mute.

Why are you so aggressive?

I have no interest in joining the ARRL.

That is not aggressive - That is concise.

Please use publicly available references.

Thanks,

[continuouswave]

Originally Posted by Viking Sailor

I have no interest in joining the ARRL.

That is not aggressive - That is concise.

Please use publicly available references.

Thanks...

The article I cited is available to the public, at a cost. The ARRL is like the IEEE. If you want to read articles they publish, you have to join or pay for them.

Were I aware of a free public resource for the article, I would have posted a link to it in my initial mention of the the cited article.

[Cadence]

Originally Posted by continuouswave

The article I cited is available to the public, at a cost. The ARRL is like the IEEE. If you want to read articles they publish, you have to join or pay for them.

Were I aware of a free public resource for the article, I would have posted a link to it in my initial mention of the the cited article.

Is the IEEE still around? Whoever said sinewaves don't have harmonics should do some more reading.