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Earlier this year, within the concluding post of a multi-part series that explored a not-as-advertised portable power generator, its already-broken-on-delivery bundled solar panel:

and the second solar panel I’d also bought for the setup (and subsequently also returned):

I discussed the primary options (serial and parallel) for merging the outputs of multiple solar panels, the respective strengths and shortcomings of the two approaches and, in the parallel-connection case, the extra circuitry that (unless already built into the panels themselves) would likely be necessary to prevent reverse-current hotspots in situations where one or both panels were in dim light-to-darkness.

Since both panels I’d bought, plus the portable power generator they were intended to “feed”, were all based on Anderson Powerpole PP15-45 connectors:

the parallel combiner I’d also bought from (and subsequently also returned to) Amazon had Anderson Powerpole connectors on both input ends, plus the output:

What if anything was inside it beyond just two pairs of input wire, with like-polarity cables soldered together and to an output strand, all within an intermediary watertight compartment? And if more, why? Here’s what I wrote back then:

Assume first that the combiner cable simply merges the panels’ respective positive and negative feeds, with no added intermediary electronics between them and the electrons’ intended destination. What happens, first, if all the parallel-connected panels are in shade (or to my earlier “dark” wording surrogate, it’s nighttime)? If the generator is already charged up, its battery pack’s voltage potential will be higher than that of the panels themselves, resulting in possible reverse current flow from the generator to the panels. Further, what happens if there’s an illumination discrepancy between the panels? Here again there’ll be a voltage potential differential, this time between them. And so, in this case, even if they’re still charging up the generator’s batteries as intended, there’ll also be charging-rate-inefficient (not to mention potentially damaging; keep reading) current flow from one panel to the other.

The result, described in this crowded diagram from the same combiner-cable listing on Amazon:

is what’s commonly referred to as a “hotspot” on one or all panels. Whether or not it negatively impacts panel operating lifetime is, judging from the online discussions I’ve auditioned, a topic of no shortage of debate, although I suspect that at least some folks who are skeptical are also naïve…which leads to my next point: how do you prevent (or at least minimize) reverse current flow back to one or both panels? With high power-tolerant diodes, I’ll postulate.

Those folks who think you can direct-connect multiple panels in parallel with nothing but wire? What I suspect they don’t realize is that there are probably reverse current-suppressing diodes already in the panels, minimally one per but often also multiple (since each panel, particularly for large-area models, is comprised of multiple sub-panels stitched together within the common frame). The perhaps-already-obvious downside of this approach is that there’s a forward-bias voltage drop across each diode, which runs counter to the aspiration of pushing as much charge power as possible to the destination battery pack…

If you look closely at the earlier “crowded diagram” you can see a blurry image of what the combiner cable’s circuitry supposedly looks like inside:

And I closed with this:

Prior to starting this writeup, I returned the original combiner cable I bought, since due to my in-parallel return of the Duracell and Energizer devices, I no longer needed the cable, either. But I’ve just re-bought one, to satisfy my own “what’s inside” research-induced curiosity, which I’ll share with you in a teardown to come.

That time is now. Since I strongly suspected my teardown would be destructive, I picked up the cheapest combiner I could find on Amazon. This one, to be precise, from the same supplier I’d chosen before (therefore presumably with the same “guts” in between the output and inputs):

In this particular case, the combiner was intended for use with Jackery portable power stations (historically based on, as I’ve noted before, either a DC7909 or DC8020 connector depending on the model), so it included native-plus-adapter support for both plug standards. Today’s patient was “Amazon Warehouse”-sourced, therefore $3.20 cheaper than the $15.99 list price. And again, I assumed it wouldn’t live past my dissection of it, anyway. Speaking of which, here it is:

Now freed, along with its associated output adapter, from clear-plastic captivity and as usual accompanied by a 0.75″ (19.1 mm) diameter U.S. penny for size comparison purposes:

Input(s) end:

Middle thirds, top and bottom:

And output end, both “bare” and adapter-augmented:

Back to the middle third for a side view. Look, it’s an ultrasonic welded seam all the way around!

I’m glad to see that at least some of you enjoyed my attempted (successfully, so, albeit not cleanly) breach of an ultrasonic-welded wall wart case at the beginning of last month.

To the Hackaday crowd: No, it wasn’t intended as an April Fools’ joke. I had no idea what day Aalyia was going to publish it, although in retrospect, excellent choice, my esteemed colleague!

This time I decided to downscale my “implements of destruction” somewhat, downgrading from a 2.5 lb. sledge to a more modest ball-peen hammer,  and to a more diminutive but no less sharp (unfortunately, this time absent a “hammer end”) paint scraper:

I’d also like to introduce you to my equally diminutive, recently acquired vise, the surrogate for the Black & Decker Workmate I used last time. Isn’t it dainty (albeit surprisingly sturdy)?

It took a few more whacks than I would have preferred (or maybe I was just being cautious after last time’s results), but eventually I got inside, and cleanly so this time, if I do say so myself:

The other side…not so much, although still not bad (and yes, to several readers’ suggestions, I also own a hacksaw, which I’ve used before in similar situations; I was just angling for variety):

All that was left was a flat-head screwdriver acting as a lever arm to pry the two halves apart:

And we’re in:

This initial perspective is of the bottom of the device:

Note the thick PCB traces and their routings. Keep this in mind when we flip it to the other side:

Speaking of which, let’s next remove those two screws:

And the PCB’s now free:

Here’s the bottom side of the PCB again, now absent the case half that previously surrounded it:

And here’s the now-exposed top half, blurrily glimpsed earlier in one of the “stock photos”, that we all really care about:

Zooming in a bit:

And now even closer, courtesy of my crude, inexpensive loupe-as-supplemental-lens setup:

Those are indeed “high power-tolerant diodes”! Specifically, they’re multi-sourced (does anyone there know if the first line “LGE” mark refers to LG Electronics?) MBRD1045 Schottky devices, variously referred to both “diodes” and “rectifiers”, the latter because their Schottky-derived low forward voltage loss makes them amenable to use in (among other things) full-wave rectifier circuits like the one seen in last month’s “wall wart”. In actuality, the two terms refer to the same thing, as a discussion forum thread I came across in my research made clear. This memorable phrase in one of the thread’s posts cracked me up (no, I won’t reveal if I agree!):

EEs are not known for consistency and precise language.

Admittedly, a circuit diagram I found in several suppliers’ datasheets gave me initial pause:

Two anode pins? Were the same-polarity outputs of both solar cells combined ahead of the diode? And if so, why were there four diodes in the design, instead of just two?

Eventually, even before doing the math and calculating that the spec’d 10 A of peak per-diode forward current would barely-at-best enable free flow of even one solar panel’s electron output (thereby, I suspect, being the primary cause, vs the slight forward voltage drop across the diodes, of my previously mentioned inefficiency results noted by some combiner users), far from two panels’ aggregate load, I’d also realized that such a setup would only achieve one of the two desired combiner objectives. It would indeed prevent this scenario:

What happens, first, if all the parallel-connected panels are in shade (or to my earlier “dark” wording surrogate, it’s nighttime)? If the generator is already charged up, its battery pack’s voltage potential will be higher than that of the panels themselves, resulting in possible reverse current flow from the generator to the panels.

But it would do nothing to current flow-correct this other key potential “hotspot” scenario:

What happens if there’s an illumination discrepancy between the panels? Here again there’ll be a voltage potential differential, this time between them. And so, in this case, even if they’re still charging up the generator’s batteries as intended, there’ll also be charging-rate-inefficient (not to mention potentially damaging; keep reading) current flow from one panel to the other.

So, four diodes total it is, two for each panel (one for the output and the other for the return), with both anode connections of each diode leveraged for a common input, and the two panels’ respective positive and negative pairs combined after the multi-diode structure. This “digital guy” may yet evolve embryonic-at-least analog and power electronics expertise…nah. C’mon let’s get real. Delusions are inexhaustible, don’cha know. Regardless, did I get the analysis right, or have I missed something obvious? Sound off with your thoughts in the comments!

—Brian Dipert is the Editor-in-Chief of the Edge AI and Vision Alliance, and a Senior Analyst at BDTI and Editor-in-Chief of InsideDSP, the company’s online newsletter.

 Related Content

• Energizer’s PowerSource Pro Battery Generator: Not bad, but you can do better
• The Energizer 200W portable solar panel: A solid offering, save for a connector too fragile

The post Cutting into a multi-solar panel parallel combiner appeared first on EDN.

India’s BrahMos missile is a milestone in new age technology and an icon of Indo-Russian defense cooperation Introduced through a joint collaboration between India’s Defense Research and Development Organisation and Russia’s NPO Mashinostroyenia in 1998, the name of the missile Brahmos is derived from the names of rivers Brahmaputra (India) and Moskva (Russia). It represents the integration of both countries technological strengths.

Land-launched and ship- launched Brahmos entered service in November 2005. Subsequently, an air-launched version was completed for the Su-30MKI fighter, which emerged in 2012 and became officially operational in 2019. The BrahMos is derived from the Russian P-800 Oniks cruise missile but has been indigenously upgraded and adapted to Indian Armed Forces specifications. It is the fastest supersonic cruise missile in active service worldwide, with the ability to cruise at speeds of Mach 2.8 to 3.0. Its speed makes it nearly impossible to detect and intercept, providing it with a decisive advantage over ordinary subsonic missiles.

Design:

Technically, Brahmos is a two-stage missile. Its first stage is a solid-fuel booster that takes it to supersonic speed, and the second stage is a liquid-fueled ramjet engine that maintains its cruise speed. The missile is stealth-designed to reduce radar detection and has the capability of low-altitude flying, particularly in sea-skimming mode. It adheres to a fire and forget policy with no further instructions after being fired, and it employs sophisticated inertial navigation supplemented with GPS/GLONASS technology for accuracies within a circular error probable (CEP) of less than a meter.

BrahMos has the capability to carry conventional warheads ranging from 200 to 300 kilograms and has a maximum range of 450 kilometers, with an extended-range division that can fly more than 800 kilometers under development. BrahMos is deployable from land-based platforms, submarines, surface ships, and fighter jets like Sukhoi Su-30MKI.

Variants:

A number of variants have been created to be compatible with various divisions of the military. These include Brahmos-A to be launched from air, BrahMos-ER for longer-range strikes and the BrahMos-NG (Next Generation) lighter and small variant being developed to be used by lighter planes and smaller launch platforms. A next-generation hypersonic version, BrahMos -II, is also on the cards, which plans to travel faster than Mach7.

Features:

Type: Supersonic cruise missile

Speed: Mach 2.8 to Mach 3.0 ( approximate 3,700 km/h)

Range: Up to 450 Km (Extended Range variant over 800 km)

Length: Approximately 8.4 meters

Diameter: Around 0.67 meters

Propulsion: Two stage-solid fuel booster and liquid-fueled ramjet

Launch Platforms: Land launchers, ships, submarines, aircraft

Guidance system: Inertial navigation system with GPS/GLONASS support

Conclusion:

In the recent India-Pakistan conflict, BrahMos missile was instrumental in the military campaign of India under ‘Operation Sindoor’. The Indian Defence Forces employed BrahMos missiles to carry out targeted attacks, having a deep impact on Pakistan’s defence setup.

India utilized BrahMos missiles along with other precision-guided weaponry such as HAMMER and SCALP missiles. BrahMos’s high speed (Mach 2.8- 3.0), precision accuracy, and fire and forget nature enabled India to target deep, the extended range (up to 800 km) of the missile granted strategic deterrence. The BrahMos missile is a symbol of India’s technological drive and strategic independence.

The post Why the World Fears BrahMos: India’s Game-Changing Missile Explained appeared first on ELE Times.

In booth 1447 at SID Display Week 2025 in San Jose, CA, USA (11–16 May), micro-LED technology firm VueReal Inc of Waterloo, ON, Canada is unveiling its latest micro-LED advances, highlighting scalable solutions for next-generation lighting, displays and transparent electronics across automotive, consumer and emerging tech applications...

Wolfspeed Inc of Durham, NC, USA — which makes silicon carbide (SiC) materials and power semiconductor devices — has appointed Paul Walsh and Mark Jensen to its board of directors. Both will serve as members of the Audit Committee...

Sweden-based AlixLabs AB (which was spun off from Lund University in 2019) says that the US Patent and Trademark Office has issued the notice of allowance for its latest patent application, US20250087487A1 ‘Formation of an array of nanostructures’...

Credifin Limited announced the launch of its new product EV Startup Loans. This product will promote entrepreneurship through EV business and deployment of active vehicles throughout the country. The EV Startup Loans will be available to any individual or company that wants to start a dealership or electric vehicle related business.

Under the EV StartUp Loans product, Credifin will provide the EV Entrepreneur loans up to Rs. Fifty Lakhs to begin with. On a need and case to case basis the loan amount can be increased going forward. With presence in over 200 locations in 13 states and expanding rapidly, Credifin is targeting 1000 EV Entrepreneurs in the next 2-3 years

Credifin has over 100 existing OEM partnerships across E-Rickshaw, L5 and EV 2 Wheeler Segment and will help the entrepreneur lendee with not just the financing but also facilitate tie ups with reputed manufacturers for setting up of the new dealership, at no cost. In addition, under the scheme, Credifin will also provide trade advance for the dealership to acquire the vehicles to be sold by them. Credifin will also offer financing of the vehicles to the end customer.

Credifin will help create EV entrepreneurs by creating an ecosystem where Credifin team will provide an end-to-end solution to the Entrepreneur. Whether it is setting up of the business, dealership, getting business leads, partnerships or help with local authorities for registration of the vehicles, Credifin’s team can assist the entrepreneurs and hand-hold them all the way.

“We at Credifin are committed to Building Bharat and what better way to do this than to make sure that our entrepreneurs have an enabling environment. Our EV StartUp Loan is a product that makes sure that setting up a business is made as easy as possible and that we are with them all through, ensuring that they not just survive but thrive. We have today, one of the biggest EV networks and we believe that the time is ripe to use this network to help individuals realize their dreams of building successful businesses in a sustainable manner”, says Shalya Gupta, CEO, Credifin Limited.

The post Credifin Limited announces a new product: EV StartUp Loans appeared first on ELE Times.

South Korea-based LED maker Seoul Semiconductor Co Ltd says that it has narrowed the market share gap with global number-2 player ams OSRAM to just one percentage point, according to the ‘2024 Global LED Market Share Rankings’ issued by market research firm Omdia. Seoul Semiconductor was the only company among the global top three to sustain both revenue and market share, while industry leaders Nichia and ams OSRAM experienced significant revenue declines amid the slowdown in the LED market...

Bluetooth channel sounding—a new protocol stack designed to enable secure and precise distance measurement between two Bluetooth Low Energy (LE) devices—is propelling Bluetooth technology into a new era of location awareness. It offers true distance awareness while enhancing Bluetooth devices’ ranging capabilities.

Bluetooth channel sounding’s use spans from helping locate devices such as phones or tablets to digital security enhancements like geofencing. It can also be used in smart locks, pet trackers, vehicle keyless entry, and access control applications.

Hardware and software solutions are starting to emerge to fulfill the potential of Bluetooth channel sounding and provide sub-meter accuracy for Bluetooth-empowered devices. These solutions include reference boards, development kits, and software stacks.

Below are two design case studies demonstrating the potential of Bluetooth channel sounding technology.

Radio board and antenna hardware

Silicon Labs’ xG24 radio board—designed to work with Pro Kit—aims to help developers create and prototype products using Bluetooth channel sounding for precise distance estimation. Pro Kit includes a BRD4198A EFR32xG24 2.4 GHz +10-dBm radio board, a dipole antenna, and reference designs. It works with either a coprocessor with an external MCU or a wireless system-on-chip (SoC) with an integrated MCU.

Another xG24 Dev Kit features a dual-antenna PCB design and a channel sounding visualizer tool to allow developers to view distance measurements in real time. Single-antenna hardware offered in the Pro Kit has fewer antenna paths and limited multipath information, which makes it more suitable for basic Bluetooth channel sounding applications.

Figure 1 USB or coin cell powered development platform with a dual-antenna design and up to +10 dBm output power. Source: Silicon Labs

On the other hand, dual-antenna hardware offers higher accuracy, better spatial performance, and enhanced multipath resolution, making it suitable for advanced applications such as key fobs and tags that demand precise distance estimation (Figure 1). Its antenna diversity also bolsters signal quality and robustness.

Software stack

Bluetooth channel sounding technology uses phase-based ranging (PBR), round trip time (RTT), or both to accurately measure the distance between two Bluetooth LE-connected devices. PBR utilizes the principle of phase rotation in RF signals to determine precise distance between two devices. On the other hand, RTT, a communication channel, refers to the duration a signal takes to travel from the initiator to the reflector and back again.

The above solution from Silicon Labs uses both, employing RTT to verify and cross-check the PBR measurements. However, Metirionic, a German supplier of wireless ranging and positioning technologies, offers an alternative to both PBR and RTT by leveraging the channel impulse response (CIR) technique for highly accurate and reliable distance estimation.

Figure 2 The channel sound evaluation kit is built around Nordic Semiconductor’s nRF54L15 wireless MCU. Source: Metirionic

Its Bluetooth channel sounding evaluation kit—Metirionic Advanced Ranging Stack (MARS)—is a low-power signal-processing upper-layer software (Figure 2). It can run on Nordic’s nRF54L15 embedded MCU, on an external MCU or processor, or on a host PC to ensure precise, reliable and real-time ranging and location accuracy for industrial, Internet of Things (IoT), real-time location services (RTLS), logistics, and secure access applications.

Related Content

• A short design tutorial on Bluetooth Channel Sounding
• How Bluetooth Channel Sounding Compares to Other Location Tech
• Bluetooth Channel Sounding Improves Distance Estimation Accuracy
• New wireless MCUs feature software radio and Bluetooth channel sounding
• Rohde & Schwarz to show measurements on novel Bluetooth Channel Sounding signals

The post Two design solutions for Bluetooth channel sounding appeared first on EDN.

I bought this Tek 453A on eBay from Germany for a super affordable 1900 CZK (around 84 USD), making it an irresistible purchase. Upon receiving it, the scope was in great shape (almost brand new). I will use this scope a lot in my analog RF projects. Anyways, the inside is so beautiful, basically a work of art, so I decided to post it here. submitted by /u/A55H0L3_WindowsXP [link] [comments]

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🎥 Спільний українсько-естонський проєкт щодо розвитку підприємництва та туризму у громадах kpi сб, 05/10/2025 - 21:19

🎥 КПІшники — вдруге чемпіони України з шахів серед студентів! kpi сб, 05/10/2025 - 21:08

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My 555 timer(up) in astable mode My flip flop D(down) done with logic gates submitted by /u/White_Septendecim [link] [comments]

My multimeters (generic DT-9205A) 9V battery died. So, I tried to replace the 9V battery with a single 18560 rechargeable battery (3.7V). I connected the battery to a small charging/protec board (TP4056), then connected the output of that to a step up converter (MT3608) (to step up the batteries 3.7V into 9V). Finally, i connected the output of the step up converter to the positive and neg of the battery terminals of the multimeter. The Problem: The multimeter doesn't turn on :0 , after some measuring with a simple LED tester, it seems: Battery gives 4Volts Charger/Prot outputs 4Volts Step Up outputs 0Volts Also, when i measure the voltage at the Vin+ and - of the step up i read 0 Volts I tested the circuit (batt+charg/prot+stepup) alone before connecting it to the multimeter and it was functioning normally, giving 9V. Here are some images of the stuff. submitted by /u/Jolly_Ad717 [link] [comments]

Uviquity of Raleigh, NC, USA (a venture-backed start-up pioneering wide-bandgap integrated photonic disinfection technologies) has emerged from stealth after a $6.6m seed-funding round led by Emerald Development Managers (an early-stage venture capital firm specializing in deep tech) with participation from AgFunder and MANN+HUMMEL (specialists in food and agriculture venture capital and advanced filtration solutions, respectively)...

We took a family trip with our grandsons to the New York Transit Museum in Brooklyn, NY. Retired subway cars were on display, some of them seemingly not that old while others dated way, way back. Visitors could freely roam in and out. I was in this one car that had been in service in 1903 which meant it predated the advent of electronics. Even the vacuum tube had not yet been invented by then.

I noticed the passenger area’s bare light bulbs and got really close to one (Figure 1). It was rated at 56 watts and 120 volts. A question came to mind as to how did that car use 120-volt light bulbs when the third rail voltage was (and still is) 600 volts DC?

Figure 1 A subway car light bulb up close showing 56-W and 120-V rating.

When we got home, I tried looking up subway car technical data, but when I came to a wiring schematic, I couldn’t read it. The symbols were indecipherable to me. Only then did it dawn on me that five such bulbs connected in series would be operable from 120 x 5 = 600 volts. If any one of the five were to burn out, all five would go dark, but then maintenance would change all five and discard four good bulbs with the one blown out bulb. It sounded wasteful, but it would have been a practical approach.

Is that the actual truth? I don’t know, and there was nobody on hand to ask, even if I had been quick enough of wit to inquire. Also, I just wasn’t smart enough on site to see if the total number of bulbs in the car was a multiple of five. Maybe one day, I can do that.

Another point about those subway bulbs is that they had left-handed threads on their bases, while household bulbs use right-handed threads. This was to discourage light bulb thefts. Stolen bulbs would not fit into light bulb sockets in households, only into the sockets of subway cars.

John Dunn is an electronics consultant, and a graduate of The Polytechnic Institute of Brooklyn (BSEE) and of New York University (MSEE).

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The post Antique NYC subway cars appeared first on EDN.

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