Craig, One aspect of the design that may be overlooked is the beamwidth of the ultrasound transducer itself. Even with a proper F/D ratio, the transducer may not fully illuminate the reflector or ins
Bob, I developed and taught for 15 years a university-level engineering course on renewable energy systems design, which was principally devoted to PV systems design. Here are some recommendations if
I did not mean to imply that microinverter designs are fundamentally bad nor that central inverter designs are RFI-free - as others have noted, the Enphase microinverters are seemingly RF quiet, and
For those who would like to know what are the conducted and radiated RFI limits in the EU and U.S., this report (beginning on p. 11) provides a nice summary: https://www.intertek.com/uploadedFiles/In
If you find out what its purpose in life once was, I would like to know. I acquired a box full of similar supplies, mostly made by PowerOne. They have relatively high amperage +5V DC outputs, and typ
Pete, I find similar patterns of power line arc noise, but I have only a single 135 foot doublet, center fed with window line, as my antenna. That antenna exhibits multiple azimuthal lobes on the hig
David, The PV modules themselves are not noisy - from the ad you linked it does not appear that the pallet of panels is accompanied by an inverter or micro-inverters. The PV modules generate DC - it'
David, The bypass diodes built into the modules can go bad (either failed open or failed shorted), but this failure mechanism would not create RFI from the DC output of the module. PV modules with fa
Jim, No disagreement that charge controllers, not just the inverter portion of a PV system, are RFI generators. The ad linked by KD4E was for a pallet of PV panels, which are devoid of any power conv
Agreed, Jim - we are on the same page regarding need for good, quiet charge controllers if a battery-backed PV system is planned. 73, Mike, K8CN ________________________________ From: Jim Brown <jim@
Similar story here, but never had much doubt about presence of multiple arc sources at different poles, all within about 1/2 mile or less from my house, based on my own DF'ing efforts. Bottom line: l
Pete, Does your noise remain constant in intensity/signal strength across the 15 meter band? If not, you may have a non-power line source to hunt. If you have an oscilloscope, place its probe across
Thanks, Ed - those are good, notable exceptions to the general trend of rain/condensation shorting out the arc path/gap. We have some transformer primary bushings equipped with squirrel guards, but t
Here's a great RFI detective story, somewhat along the lines of WD8DSB, Don's story of the splatter of an AM broadcast station: https://www.theguardian.com/australia-news/2021/oct/26/alien-false-alar
Chris, NK7Z's direct experience indicates that without LOCAL regulation of non-commercial tomato growing operations New Jersey is likely to be overwhelmed by new RFI sources. If the state legislature
Jim, There was some extended discussion on this forum in May 2021 regarding minimal RFI inverters. The general consensus was to avoid SolarEdge at all costs, and Enphase was mentioned as having low R
Curious to know if readers of this list have experience with RFI generation from any of the Zamp product line, especially charge controllers for battery-backed PV systems? Mike, K8CN ________________
David, You didn't conclusively identify the signal source that was opening the squelch. However, your body may be the necessary attenuator to prevent the squelch opening in just the right body postur
APsystems is the manufacturer of the YC600 micro-inverter. https://usa.apsystems.com/products/apsystems-yc600/ I had not heard of this company until your post, Tony. 73, Mike, K8CN __________________
Hi David, The Solyndra panels generate DC and have no attached microinverters/optimizers. They are not in themselves RF noise generators. Others may wish to comment on the virtues of different charge