Recent content by AE4KR

Here's a detailed blog post by a local engineer on what was done to "clean up" the inverter in a UPS, which was destroying radio reception at a remote cabin: https://ka7oei.blogspot.com/search/label/inverter%20noise

I just discovered this interesting read. I've been trying to imagine a way to use the earth as a heat source/sink. My application is a remote transmitter, off-grid solar powered, LiFePO4 storage. I need to both dissipate about 250 watts continuous heat when the transmitter is operating, and keep...

Mike, I think we're all struggling to understand what problem the diodes would address, and where you'd plan to install them. So far, it sounds as if they'd be redundant to the diodes already in the panels. EDIT: Ahhh...building your own panels from individual cells. Got it. Using an...

Most commercially manufactured solar panels have diodes built-in to protect against back-feeding and shading issues. There are a few applications where external diodes could be useful. If you're using parallel batteries which each have their own BMS and/or thermal shutdowns, diodes could be...

You see them in your results in exchange for receiving the service provided by Google, and you know that's how Google makes its money before you go there. By your definition, TV commercials would be spam. They're not. Amazon investors knew that business would take time to mature. They took the...

Is this excessive absorption time for a 280 Ah cell? I thought 0.1C was the charge rate at which they were considered full. Thinking out loud, maybe that's the rule of thumb if max charge voltage is set for 3.65....

That panel only makes 60 watts with an MPPT charge controller. Without a controller or a PWM, the battery will pull the panel's output voltage down to the battery voltage, and the panel will provide in the neighborhood of 3 amps. So in your application it's now a 35 - 45-watt panel. If you have...

True, but at least in this case, when customers ask what's in them, the manufacturer tells us, and even provides advice on what to order if you have to have prismatics. That level of candor is pretty rare, especially from China.

I did weigh the battery - 23.4 pounds without the packaging.

I don't think they're analogous. I'm not aware that the company ever advertised it, or put it on a label. Again, this is a bunch of deep hobbyists discovering changes in a product that won't matter to most buyers, and was never claimed or promoted by the company. A review by Will does not lock a...

How about a bit of perspective. This is like posters on a car mechanics forum calling out Ford for failing to disclose the metallurgical composition of its crankshaft main bearings on the 2.0L EcoBoost engine before purchase, or getting mad if they adjust it without telling buyers. We're...

...and the refund has landed. The odd thing is, the delivery was made on the 12th, within the originally predicted time window (March 10 - 16.) In fact, the late-shipping credit landed in my account on the 15th, a day before they even had promised delivery of the battery. I'm thinking they...

The battery arrived today. It showed a shipping origination address in California. It was nicely packed, and included the bolts for the terminals. I'm keeping the foam caps that protected it in the box, in case I want to insulate the battery from the floor of an enclosure. The battery was...

Almost certainly. The harmonics of a switching power supply taper off as they go higher in frequency. A low-frequency switcher's harmonics are then naturally going to be less problematic, because at any given RF frequency the harmonic multiple is much higher. The legacy MorningStar controllers...

The starter battery has thinner plates, and many of them, to allow generating hundreds of amps in short bursts for starting an engine. If they're deep-cycled, the material they lose from the plates can leave the plates deformed in a way which can't be restored by charging. The deep-cycle...