charging your small electronic devices whilst dinghy cruising

Whilst waiting for the new 24W Big Blue solar panel to arrive, I am now turning attention to investigating whether I can establish a connection between my Powermonkey traveller and my ICOM M23.

The Big Blue 28W solar charger 

A 1.7mm x 4mm male barrel jack into the radio charge point

The 12v outport on the PowerMonkey Traveller uses a 1.7mm x 5.5mm male barrel jack. The power bank gives out 5v 700mA or DC 12v 0.8A. It is a 10,000 mAh capacity. It is quite old now and there are better integrated solar charger/power banks out there now. But, as always, I get sentimentally attached to pieces of equipment that have served me well and accompanied me on my travels. This power bank is one such piece.

The other power bank I use is an iMuto 20000mAh with two 5v/2.4A USB ports.

The VHF radio is charged by a 1.7mm x 4mm male barrel jack - the wall charger giving out 6v 0.6A. It has a 3.7v Li-ion battery 1500mAh.

I could just buy a spare radio battery - around £20 and charge both up before I leave home. Each battery will last around 10 hrs. So three days sailing possibly and then I could use my spare radio which takes AA batteries for the remainder of any trip - but that would chomp through batteries and I am trying to be sustainable here.

I am trying to avoid installing a 12v system in Arwen - instead spending money on items that will be used across a range of activities from climbing and camping trips to cycle  and canoe touring.  I have elaborated on these principles in previous recent posts.

I am no electrician but I am assuming that a USB cable with a male barrel jack on the end running from either power bank to the radio isn't going to charge it - power bank out put is 5v/2.4A and the radio input from its wall charger is 6v 0.6A.

So I need something to increase the 5v to 6v I am assuming.  I have been looking at something such as this

https://www.amazon.co.uk/USB-voltage-converter-cable-negative/dp/B011LO5KJE/ref=mp_s_a_1_14?keywords=5v%2Busb%2Bto%2B6v&qid=1560249761&s=gateway&sr=8-14&th=1

This item is a 5v USB to 6v 1.05A converter with centre positive polarity (what is that?)
I have contacted the seller 'MyVolts' who are based in Dublin - asking for their help and advice as to whether this connecting cable will link the power banks and radio correctly and I await their answer.

I know the simplest solution is to put in a 12v system in my spare galley box with appropriate usb and cigarette sockets and possibly an inverter/converter affair. However, it is one more thing in Arwen and something that I cannot then use across my other outdoor activities.

But I'm not powering a bilge pump or a GPS/chartplotter. All I need to recharge are GoPro and camera batteries, my mobile phone, a tablet and the VHF radio. All except the latter also go with me when trekking, canoeing, camping, cycle touring and climbing. The Big Blue 28w solar charger recharges tablet, phone, batteries and power banks. It won't power charge the VHF.

I cannot be, surely, the only dinghy cruiser who doesn't want to install a 12v system but does want a flexible, sustainable approach to charging small electronic devices?

I will let you know what MyVolts come back with and what solution I find in my next post.