Here's my inverter for power outages: http://jons-math.bravehost.com/inverter.html I've got it on a shelf to clamp on to my truck battery. ...

Here's my inverter for power outages: http://jons-math.bravehost.com/inverter.html I've got it on a shelf to clamp on to my truck battery. Then I'm running an extension cord through the wall of my trailer, turn the circuit breaker off and plug into the circuit.

I want to try this emergency battery charger: https://www.ebay.com/itm/185836877680 150W output? Or do they mean 150W LED bulb? Perhaps...

I want to try this emergency battery charger: https://www.ebay.com/itm/185836877680 150W output? Or do they mean 150W LED bulb? Perhaps 10W real output? What's the benefit of twin cylinders vs. the single cylinder version?

Anyone aware of such a thing? Clearly, one can achieve that just by putting a thermistor in series with an ordinary resistor, but my UPS...

Anyone aware of such a thing? Clearly, one can achieve that just by putting a thermistor in series with an ordinary resistor, but my UPS seems to contain a single component that behaves that way - perhaps less than 1% at 20 Celcius - it's in the circuit that controls the battery charging float voltage. Did they perhaps exist 20 years ago (when my UPS was made), for some reason? Sylv...

Who makes a good stable carbon pile? Stable as in it maintains its resistance as current is varied. 200 amp range, 100 VDC. Currently using a...

Who makes a good stable carbon pile? Stable as in it maintains its resistance as current is varied. 200 amp range, 100 VDC. Currently using a battery load tester but I want something I can mount on my own equipment. e.g. I have DC motor that I want to voltage up to see how it draws.

I drive my pick-em-up truck every few months. So the battery is dead when I go to use it... like today :-( I'm looking for recommendations...

I drive my pick-em-up truck every few months. So the battery is dead when I go to use it... like today :-( I'm looking for recommendations for the _best_ (*) float charger I can buy to just plug the truck into when it's parked. (*) Cost no object. ...Jim Thompson -- | James E.Thompson | mens | | Analo...

While looking at a single sideband receiver project that may be coming up I checked the usual suspects for quadrature demodulators. Many...

While looking at a single sideband receiver project that may be coming up I checked the usual suspects for quadrature demodulators. Many won't (technically ...) go much below 100MHz. Some do and I need to be more in the 5-10MHz region. But they are massive guzzlers when it comes to draining the battery. Like this one which slurps a whole watt (!): http://cds.linear.com/docs/Datasheet/5584f....

Cart with 2x 12v 33Ah progolf AGM lead acids. 1.5 years after fitting new batteries the available range is down to below 10%. I'm not clear what's...

Cart with 2x 12v 33Ah progolf AGM lead acids. 1.5 years after fitting new batteries the available range is down to below 10%. I'm not clear what's gone wrong. The charger in use has been a cheap chinese one with 2x13.7v=27.4v output. Single stage charging only. It has always been promptly charged after use, and never run below 50% charge. I checked the battery voltages after charge, they wer...

Does anyone have any experience swapping out old lead-acid batteries for Li-ion equivalents in a UPS? I see these batteries advertised as...

Does anyone have any experience swapping out old lead-acid batteries for Li-ion equivalents in a UPS? I see these batteries advertised as replacements, but I'm concerned about their safety in this application. New Li-ion UPS systems seem to be extremely expensive.

I need an MP3 player that runs 24/7. All the ones I have shut down and switch to file transfer mode when you plug in USB. So, I think I need a...

I need an MP3 player that runs 24/7. All the ones I have shut down and switch to file transfer mode when you plug in USB. So, I think I need a 1.5V AAA battery eliminator. All my wall warts use a TL431 as regulator. If I could find a replacement with 1.2V-ish reference in TO-92 I could just drop it in and change one resistor to get 1.5V. What's a good cheap, shunt-regulator IC that wi...

I've got a battery management unit that is reluctant to demonstrate functionality. The vendor's terminal com software seems non-functional...

I've got a battery management unit that is reluctant to demonstrate functionality. The vendor's terminal com software seems non-functional (will not install). So far the only evidence of life is a control line (one of three) hard on, and rare /XFFE /FFF signalled outputs on the rs232 port. Internal DC-DC fails to power LEM sensor. Balancing terminals seem inactive. Can anyone recom...

I have a "dumb" NiMh/NiCd charger. For 9 volt batteries, it specifies 25 milliamps. The charger manual gives this charge...

I have a "dumb" NiMh/NiCd charger. For 9 volt batteries, it specifies 25 milliamps. The charger manual gives this charge formula. Charging time(h) = 1.2 x battery capacity (mAh) -------------------- charging current (mA) 13.44 hrs. Is is formula useful or is there something better that factors in the starting Voltage ? Thanks.

I'm looking for a low cost contact material that can withstand being exposed to unconditioned warehouse conditions for months without the surfaces...

I'm looking for a low cost contact material that can withstand being exposed to unconditioned warehouse conditions for months without the surfaces becoming corroded or oxides. The shape of these will be similar to D cell batteries with a spring on one side and a flat contact on the other. The device is not a battery but mounts similarly and must work reliable on first install. No jiggling ...

Folks, Got a Dell Vostro 200 mini tower with XP on there that seems to be a bit off in the realtime clock lately. Around five years old so...

Folks, Got a Dell Vostro 200 mini tower with XP on there that seems to be a bit off in the realtime clock lately. Around five years old so needs a new 3V coin cell on the mobo. In order not to lose all the setup stuff, can those CR2032 coin cells be hot-swapped while the PC is running? Of course using ESD straps, being careful and all that. -- Regards, Joerg http://www.analogco...

https://youtu.be/FSwZQtqWyHw Can that whining noise be easily eliminated? I am assuming its origin is easy for some to guess. It uses...

https://youtu.be/FSwZQtqWyHw Can that whining noise be easily eliminated? I am assuming its origin is easy for some to guess. It uses brushless motors controlled by an "electronic speed control" (ESC). There is a large cap across each ESC supply plus and minus. I tried adding a 1000 ?F low ESR capacitor on the battery input but that didn't help. Thanks.

I'm setting up a UPS for my computer/comms equipment using an inverter/charger and battery from Amazon. The equipment draw is only about 40...

I'm setting up a UPS for my computer/comms equipment using an inverter/charger and battery from Amazon. The equipment draw is only about 40 watts measured with a Kill-A-Watt, but all the associated wallwarts use capacitive-input switching power supplies. That means they only draw current at line peaks. My seat-of-the-pants guess is that the duty cycle is around 10%, meaning that the aver...

As part of an experiment with solar, I want to drive my 220V 3kW immersion heater with a suitable diode so that the effective power is ~1.5kW...

As part of an experiment with solar, I want to drive my 220V 3kW immersion heater with a suitable diode so that the effective power is ~1.5kW and can be driven by a smart switch so that it doesn't suck too much out of the 9.5kWh battery or solar panels.. What diode? This is UK spec. -- This email has been checked for viruses by Avast antivirus software. www.avast.com

...

https://www.electronicdesign.com/technologies/test-measurement/whitepaper/21140081/warning-your- dmm-is-discharging-your-battery-cell?utm_source=EG+ED+Today&utm_medium=email&utm_campaign=CPS200 828010&o_eid=7322A4702401H9R&rdx.ident%5Bpull%5D=omeda%7C7322A4702401H9R&oly_enc_id=7322A4702401 H9R It's sad how bad the electronics press has become. -- John Larkin Highland Technol

I bought the following 4A 5V supply adapter:...

I bought the following 4A 5V supply adapter: https://cpc.farnell.com/stontronics/t6819st/ac-dc-power-supply-5v-4a-2-1mm/dp/PW04378?st=5v%20po wer%20adaptors with the aim of trying it as an alternative supply for my 16 year old curtain controller circuit. At present I successfully use 3 x AA Nimh batteries, delivering a voltage of about 3.8 to 4.1 V (measured at the battery terminals). Current

I dread all those extension cords when using the hedge trimmer and other stuff. I found that if I connect the E-bike battery of a friend to it...

I dread all those extension cords when using the hedge trimmer and other stuff. I found that if I connect the E-bike battery of a friend to it the hedge trimmer runs somewhat slower but reliably. It had 53V DC. Those machines contain brush-type universal motors, probably with a compensation winding but not sure. Is is safe to run these with 40-60V DC over long periods of time or is ther...