Many thanks to SWLing Post contributor, Anil Raj, who writes:
I wanted to share a small but useful hack with your readers.
I use a common garden variety smartphone “Powerbank” 10,000 mAH Li Ion pack to power my Sony 7600GR which is perfectly happy with the 5V which the pack supplies. [See photo above.] I see no reason why this won’t work with other radios which require a 6V supply.
As you can imagine, the setup typically lasts for many weeks of extended daily listening and recharges in a jiffy. However, one needs to sacrifice a USB cable by soldering a DC plug at the other end. Haven’t bought AA batteries in a long time…
Thank you, Anil! What a simple but useful hack. The best part is, battery packs/banks are very inexpensive these days and, I for one, have a number of USB cables I could sacrifice for the job!
Any updates on a suitable USB power bank currently available that is RFI free?
I need one that is compact and can be attached with velcro to the radio in question.
I am using a large solar/hand crank power bank with my Tecsun PL880. It runs from a standard 18650 3.7V lithium cell, and has a standard USB mini connector. This works very well, with no noise from the power bank that I can detect on any band. I also have 2 spare 18650 batteries and an ac charger. I bought them because they are much higher capacity than the one that came with the radio. (5200Mah vs 2000Mah). With this setup, my PL880, my phone, mp3 players, etc…can run indefinitely without AC power.
Hi Anil, evidently the power pack you are using is fortunately an RF-quiet model. None of these contain a true 5 volt DC battery (there is no such thing to my knowledge) but rely on a DC-to-DC switching power supply–and these are usually rich in harmonics (noise). Some power banks are incredibly noise when hooked to a receiver, others are fine (especially if you only listen to stronger stations which helps drown out a small amount of interference).
A ferrite choke or toroid of the right “mix” (31 material is good for most of HF) can help with reducing RFI noise if you encounter any. This site is a good source: http://www.kf7p.com/KF7P/Ferrite_chokes.html
HI Guy, you are right, typically most such packs probably use regular 3.7V cells that are stepped up with a DC/DC circuit. I was sceptical about using them as a power source but when I tried it out I could hear no difference between using the internal AA supply and the power pack which in itself is intriguing. I did extensive A/B testing on a variety of weak signals and heard absolutely no difference so I’m pretty happy!
The receiver will also run with a smartphone charger connected directly to the ext. DC input jack but that is completely unusable except for listening to local FM.
Anon sells a USB cable with a plug to match the Tecsun PL – 600/660/680 radios.
I do almost the same thing with my sdr’s. I have a Halo power bank from QVC that has an outlet to jump a car battery. That’s mostly what it’s marketed for. But it also has two USB 5v Jacks and it’s also an inverter for AC powered equipment. Flashlight too.
I use the USB Jacks for my Afedri, my SDRplay and my CCW sdr’s, and the AC outlet for my Win Radio DDC-G31.
Works well for portable use as well as base use to keep everything off the mains power and to keep AC line RFI at bay. It needs a charge once a month or so, but it’s an excellent radio power source.