Sunday, June 27, 2021

Two Great Little Power Banks

 I keep telling myself that I have enough power banks, but then I buy another. Except when I buy TWO.

I saw a couple of lovely little 10Ah power banks, and the specs intrigued me. One claimed to support BOTH QC 3.0 and PD 3.0. The other claimed to support both as well, but I couldn't get PD to work on it. Maybe I did it wrong. I'll try again.

The Ainope power brick is the one that supported both right out of the box. It's a VERY small power bank, smaller and lighter than my other 10Ah units, with a shell that looks to at least resemble carbon fiber, but probably isn't. It has a very bright LED 3-digit display, to show the percentage of available power. I connected each of the QC USB-A sockets to my IQ32 using a QC "magic cable" I bought pre-made on Amazon. Both powered the radio just fine. I connected my PD Magic Cable Mark II to the USB-C connector, and it also powered up the radio without issues. I haven't done any stress testing yet, but plan to soon.

The other, by Silicon Power, is definitely supports Quick-Charge on the two USB-A sockets. The
documentation is a little vague on the USB-C connector. I saw conflicting information, at one point saying it only accepted input on the USB-C connector, but at other points claimed it was also PD output. I tried to use it with the IQ32 on the USB-C connector, and it did not power up. I strongly suspect it only partially supports PD output, at only 5V and 9V, but not 12V. I will double-check this later. But as with the Ainope power bank, it worked perfectly with a 12V Magic Cable designed for QC, and powered the IQ32 perfectly. It's not as small or light as the Ainope, but it has a different benefit: It is currently on sale for $24.99 with a $10 off coupon -- so it essentially costs only $15 for a 10Ah power supply.

I will be testing these banks to see what their lifespan is, and I'll test the Silicon Power PD socket with my QCX, which will work on 9V. It doesn't really matter to me if it works on PD or not, as I only purchased these two power banks to use with QC. Both can, at a minimum, be charged using a PD charger. 

Ainope 10Ah QC/PD Power Bank: $26.99 w/$2 off coupon.

Silicon Power QC Power Bank: $24.99 w/$10 off coupon

Coupons are only currently available for these items. If you read this some time after I published it, you may miss the coupons.

Thursday, June 24, 2021

More Research on USB Power Bank Use With QRP Transceivers: Qualcomm Quick-Charge

Good news, everybody!

No, this isn't Futurama, but sometimes I think it should be. There are wonderful things happening in the tech world in recent years, wonderful things that stagger the mind.

Even the small stuff is really, really cool!

In my presentation, I mentioned that the PD trigger boards I use for my "magic cables" can't help with non-PD power banks that have "QC", or Qualcomm Quick-Charge protocol instead. I proposed that it be the topic of yet another article, and that someone else interested in it might want to write it. Well, I take that back.

Because this is my article for just that!

I happened to check to see if QC could even be used for this, and found already-extant boards for Quick-Charge that pretty much do the same thing as the PD trigger boards. Moreover, there are pre-made cables in a variety of voltages! QC doesn't provide the high power that PD does, but the top voltage it provides is 12 volts, at 1.5 amps! This is perfectly adequate for all of my 5w QRP radios!

There's only one very small snag...if you even see it that way. The pre-made cables I've found have 5.5x2.5mm barrel connectors on them. Most QRP radios are sold with 5.5x2.1mm sockets, including the Elecraft KX3 and my HobbyPCB IQ32. So I looked for -- and found -- 2.5mm pin to 2.1mm pin adapters. I bought a couple of cables and a couple of adapters. The last piece arrived an hour ago. I plugged a cable into an adapter, plugged that into my IQ32, and checked my power banks for the QC legend on one of the USB-A sockets. Finding one, I plugged it in and flipped the switch on the radio.

It started right up. Turning on the external speaker, the 80m CW segment blasting from it. It works quite nicely! I haven't done any stress testing or timed operations, but it appears to work just fine. There are some very new versions of QC that will provide up to 22V if the source will deliver it, but 12V is a common top voltage for such applications. Some will go from 3v to 22V in .2v increments. I'm concentrating on the ability to supply 12V for the majority of QRP CW transceivers. I haven't seen a battery bank that supplies more than 12V under QC, because most QC power banks use USB-A sockets, and those are not rated for higher voltages.

The cables I bought were by JacobsParts, the same company I got my tiny Power Delivery trigger boards from only a couple of weeks ago. They also had a separate board, to which you can attach your own wire to connect it to your radio. It has a USB-A plug on the end of the board, and, like on the PD board, solder terminals for your wire. These options remove the need for a jumper cable between the power bank and the magic cable; you can connect it directly to the power bank and the other end to the radio. With the separate board, the board would plug into the power bank, and the wire would then run to the radio.

There are a LOT of power banks out there that don't support Power Delivery, but DO support Quick-Charge. These cables and boards will support QC 2.0 through QC 4.0, being forward compatible. As with PD, the power bank has to support the voltage you want, and some do not have 12 volts available, so you won't be able to use that power bank with these cables on 12v radios. If the top voltage it provides is 9v, you CAN get a 9v cable or board, and use it with a radio that will run off 9v, such as my QCX. 

So if you don't want to buy new PD power banks to take advantage of this option, check the ones you have to see if they have Qualcomm Quick-Charge at 12v. You may find that the old 10Ah power bank you bought for your phone supports QC, since it is an older protocol, and you'll be able to use it on your radios with this cable or the separate board and your own wire.

JacobsParts USB-A QC - 12v/1.5A 5.5x2.5mm coaxial plug:

UxCell 5.5x2.5mm female to 5.5x2.1mm male adapter:

JacobsParts USB-A QC - 12v/1.5A fixed voltage trigger board: (other voltages available)

Friday, June 18, 2021

USB-C PD "Magic Cable" version II

Jim Fisher AJ3DI from the Phil-Mont Mobile Radio Club asked me back in May if I'd do a presentation on my USB-C Power Delivery system for QRP radios, since my original article (posted here and published in QRP-ARCI's QRP Quarterly, July, 2020) was published in a recent issue of The Blurb, the PMRC monthly newsletter. How could I say no to the Jedi Master? The presentation went extremely well a week ago on June 9th. 

You can see the slide deck I used here:

And you can watch the Zoom/2m Repeater meeting, complete with the presentation, at:

While preparing for the presentation, found out that the original PD Buddy Sink board by Clara Hobbs I bought from was no longer available, so I did some shopping on Amazon to find some replacements. I'd used some other PD sink boards, that I detailed in another article on this blog about the subject, but didn't really find anything I liked well enough to make a cable using one. 

What I mostly found earlier this year were sink boards that would cycle through a series of configuration settings when you pressed a small tactile button on the PC board, a method I did NOT particularly like. It was far too easy to wind up sending too much power to the radio, since there was no actual feedback to tell you what setting the board was on. You'd have to test it with a DVM every time, which is very impractical. I have a tiny PokitMeter brand micro-DVM/single-channel oscilloscope the size of a keychain fob, that works in tandem with an app on my phone that I could use to easily test the voltage selected, but it really wasn't what I wanted to do. So I waited. My patience would be rewarded.

It was, and a little more so! I found that the PD sink (or trigger) boards had gone through a major evolution during that time, resulting in two major shifts in the boards now available: They're now extremely tiny, and they no longer rely on a button-press or serial terminal programming to select the output. Under most circumstances, you'll want a static voltage/amperage setting, and in my circumstance, that's precisely true. I want to set my sink boards to 12 volts at the maximum current available. So I was very pleased when I discovered that there were now PD sink boards barely larger than the USB-C jack it bore! 

There are two main varieties: 

A) Boards that can be solidly set for a particular voltage by jumpering PCB pads with a solder blob, and... (

B) Boards pre-set for a specific voltage at the factory and sold as an option at purchase. Such as 12 volts... (

I bought some of each type. Some of the jumper-controlled boards provided the whole gamut of supported PD voltages. I got some of the universal boards that can be jumpered for 5,9,12,15, and 20 volts (the red ones, above), a couple that provided 9v and 12v, and I got a 5-pack of the blue board above, that could be ordered for any single voltage desired. I chose 12v, obviously. ALL of the above boards will provide up to 5A of current, even though the maximum current for Power Delivery is 3A. That's fine with me!

I made a "proof of concept" cable using a  5.5 x 2.4 mm coaxial plug with screw terminals, attaching the contacts to a wire pigtail that I soldered to one of the 12v/5A sink boards. It worked, but the quick-connect coaxial plug I used had too large a central pin size, so it would drop out when nudged. 

This was unacceptable, so I attached the pigtail to a longer piece of the same thin zip cord with a proper 5.5 x 2.1mm right-angle DC coaxial plug. I was still experimenting, so I just used solder-seal butt splices to replace the mismatched plug with the screw terminals. It looked awful, with electrical tape still insulating the board and covering the solder seal splice job. But this one worked reliably and solidly, not losing contact if jostled. 

Now it was time to make the actual Magic Cable II. I removed the electrical tape from the sink board, desoldered the wires I'd attached, and cleaned the pads with solder wick. Some isopropyl alcohol made short work of any remaining flux. Then I shortened the wires coming from the good plug to about 10" long, stripped and tinned the ends, and soldered them to the pads on the PD sink board. I gave it a single wrap with electrical tape as a precaution, then I slipped on a piece of marine-grade, glue-lined heat shrink tubing and used my hot air rework pencil to shrink it and seal it around the board and the wire. I tested the result, and it works perfectly.

I also found a short but very heavy-duty USB-C/USB-C jumper cable. This cable is stubby, only about 6" long, but is flat with thick conductors under a reinforced "FlexCore" outer cover. It'll take maximum PD power and data, rated for 100W (20V @ 5A) and 10 GBPS of data transfer. I only intend it for power, so I chose a cable that'll take the 12V for a QRP radio without any question.

The radio I used for the test is my HobbyPCB IQ32, an all-band, all-mode 5W SDR transceiver. I have a small steel plate on the lower left corner of the faceplate, where my tiny Supmotor paddles reside. The base of these paddles is a very strong neodymium magnet. It's the smallest set of paddles I own, the body being only an inch on a side, and the fingerpieces sticking out another inch. The only paddle I have that rivals it would be my NOARC "Te-Ne-Ke" (Teeny Key), that's about the size of a pack of gum. This paddle comes in a little steel can, embedded in foam, including the paddle (with magnet base), a stick-on steel plate, a hex wrench to adjust the tension, and a 3.5mm jumper wire. It's a very comfortable paddle to use, despite the size, and it is easy to adjust for as light or as heavy a touch as you want.

I tested the setup with 3 different PD USB-C power banks: A 10Ah Monoprice "Obsidian" PD power bank and two 20 Ah RavPower "Pioneer" PD power banks, one an older model with a digital readout showing power level, and a newer model with fewer ports that uses LEDs to indicate remaining power. I will be testing with other radios and some other PD power banks later. I've also ordered more of the 12V sink boards and some 5.5 x 2.1mm DC coaxial power pigtails, since I'm lazy and don't like soldering small connectors. This will let me make a few spare Magic Cable II's in case I ruin or lose one, and leave me some sink boards to install in radios I'll build in the future. I'm looking forward to being able to just plug a USB-C cable directly into a QRP rig!

A note on the availability of the power banks I typically use: This month, all of the RavPower power banks are unavailable from Amazon, as Amazon has stopped carrying several brands, of which RavPower is one. Others they stopped carrying were Aukey, TaoTronics, Vava, and Mpow, all subsidiaries of Chinese company Guangdong SACA Precision Manufacturing. The reason cited was that these brands have been allegedly engaging in a practice of giving gifts in exchange for good reviews, which is against Amazon's sellers' agreement. The Monoprice Obsidian bank I used is no longer available, but it was discontinued. (Monoprice is owned by Amazon, in case you didn't know that.) You may still be able to buy the RavPower devices from other sources, including the RavPower website -- though some of them were simply linked to Amazon pages for sale. I expect RavPower, and the other sites removed, will be changing their ordering so they no longer point to Amazon.

For more information on the delisted brands, visit: