Sunspots and aerial views [050]
Greetings from the shack...
HERE
I’m in the shack, posing with a Turner microphone that I only ever use to play harmonica through. Thanks for stopping by.
Conditions have been not half bad recently. I managed to get Malawi and Angola on 10 and 12m with my 80m loop. But have mostly been playing on the repeaters.
THERE
Last night saw me head to the Hunts Hams monthly meet up and we had an auction to look forward to. People could bring in their own gear to place alongside a table full of silent key equipment.
I watched a box of fancy PL259’s go for a fraction of what they were worth and a load of interesting stuff go for pennies.
I picked up a lovely Revex S20N antenna switcher for a few quid, a HYT mobile 70cm radio which I shall use to monitor the local repeater, and a small thing pictured with the switcher below.
I thought it might be some kind of attenuator but Steve G1KWF thought that the 820 ohm marking could mean it’s for matching the impedance between 75 and 50 ohm coax. He his way smarter than I’ll ever be so I’ll take his word for it. I wonder if it could be used to listen to VHF-UHF via a TV antenna.
Sadly the only person that knew what it was really used for was David G7DIU (sk).
Travel for me has been car based between England and Wales and no radio to talk of other than catching up with friends as I pass their QTH. A mobile rag chew always shortens my trips and makes being stuck in traffic far more interesting.
I have figured out a decent way to carry my HF gear on my pushbike. Just from A to B, not to operate. Although that would be worth a try sometime. It’s a rack bag that should take the iCom 705 plus antennas. I’ll share photos when the sun starts to shine more and the days get brighter. Nearly there.
Spotted this history of two way radios. It’s basically an advert. But for radio. So that’s ok in my book.
GEAR
This looks like a simple HF vertical build for portable operation.
[Some of the following words appeared in this issue of my other newsletter.]
How do you power your radio gear when out in the field? Or camping.? Or practicing for the end of the world?
I'm certainly no expert when it comes to building small solar power systems, but I do have a number of my own set ups which I have acquired over the years. I was playing with solar powered comms ten years before I was a licensed amateur radio operator.
[I’ll drop amazon links below as I find it’s a minefield buying solar gear from overseas as sometimes the stats that are given bare no resemblance to what the technology delivers. And at least with Amazon, you can send stuff straight back for a full refund.]
Personally I tend to assemble simple setups and use folding solar panels for portability. But here in the shed I have larger professionally fitted panels on the roof, small panels in the windows, as well as simple semi-portable set-ups I use to power my radios. Like this one.
This is just a 10W 17.5 volt panel (0.5714A) (out of an old Maplin solar suitcase) plugged into a 72000mAh 266.4Wh portable power station. I’m trusting the internal charge controller will keep things safe. But I still charge outside when I’m not able to keep an eye on it. The battery powers a scanning radio so only really needs topping up. With that small panel it would take around 27 hours of bright British sunshine for me to fully charge the battery from flat. I have a much more portable 25W folding panel If I plan to transmit as well as receive.
I’ve used this for charging phones, ham radios, tablets, satnavs, head torches, cameras and anything that will take USB power.
You can get the bigger more cumbersome panels as cheap as 50p/watt but the compact folding units can be expensive. Sometimes £1-£2/watt.
This 60W folding panel (£54 after discount) is something I’d consider investing in for a kayak or camping trip as it’s relatively compact and easy to carry. You could charge most things with just daylight (normally at half the panel’s stated wattage) but bright sunshine would obviously be better.
Should you want to have a go at building your own small system with panel charge controller and battery then this article How to build a small solar power system has some great tips.
If I was to step things up a gear, I might go for what my friend James has, the Sunology system. You can (local electrical regs allowing) plug it straight into a mains plug to offset your electric bill. Bimble Solar also have a great reputation for supplying kits.
ONAIR
If you have been listening to the 4m band in Cambridgeshire UK recently you might have heard me calling “G5DOC test test test”. Over and over again. For days.
I have had no end of issues with my 4M antenna (Sirio CX4-68) and as it’s my favourite band I’ve been hard at trying to sort it. I have had the antenna up and down a number of times as I tried to work out why the SWR keeps creeping up over 1:3.
I changed the plugs on the coax, swapped out the coax, checked to see if the u-bolts were earthing the bracket to the pole and adjusted the length countless times between ground tests and the mast. I stuck it in a garden table to work on, but think my massive moist hedge might have made things a little harder. [Not a euphemism or the best sentence i’ve ever written.]
The Sirio CX4 antenna is famous for people drilling out the drain plug at the base of the antenna. Not something I did on instillation as I have the later version. I have now though. Plus I dried out the insides with a hairdryer and a stint in the airing cupboard. Yet still the SWR was around 1:3.
As a last resort (as I did not want to break into the base), I poured a little rice into it. This also collected some moisture and I can now tune the antenna to 1:2.
So I will use it at that while I look around for something different to try.
Here are a selection I could make or buy… 4M 70 MHz antennas but I have a feeling I might try Ceecom’s 4m half wave dipole. It looks well made and I’m told they are about to make a fresh one. If I do pick one up I’ll let you know how it performs.
Thanks to Clive 2E0OZX who has often been on the end of the radio assisting and giving signal reports. He has just loaned me a 4M Slim Jim antenna to test alongside the 4M di-pole I have been using as a back up. I’ll report back on that as if it works well it will make a great portable 4M option.
ELSEWHERE
This building looks interesting.
The Gareth and BillCast from last year discussed eLORAN and GNSS. Worth a listen if you missed it. And thing look like they are still developing. If you are not aware of eLoRAN (Enhanced-LORAN), it’s the latest of the low-frequency LOng-Range Navigation (LORAN) hyperbolic systems, and provides a Positioning, Navigation, and Timing (PNT) service for all modes of transport, be you on land, sea or in the air. Infrastructure is being installed globally with a renewed interest in Europe.
The QTH app looks interesting for playing with APRS on a Mac but I think $30 for a licence to transmit is a bit steep. It’s free to listen only though.
Is there such a thing as TOTA? (Trig points on the air). I guess it would be very similar to summits except round my way there is very little in the way of a hill let alone a summit. Here is a handy trig map should you want to activate some trig points.
If you can’t get behind this WSJ paywall it looks like the US government might force car companies to shield the cables on the latest cars as the high level of computerisation is making it difficult to pick up AM radio. There are over 4500 AM stations in the US but the US Government also uses AM for national emergency broadcasts. It also appears both the right and left would like to keep AM radio alive.
Did you know that if you support this publication with a Founding Member subscription you get my more regular, slightly more eclectic email FOC.
My friend Ruth takes her foundation exam tomorrow. Please spend a moment to warm the ionosphere with your best wishes. Good luck Ruth!
FINALS
Thanks for reading and I hope subscribing. Feel free to share this newsletter to others who it may resonate with.
You are some of the more curious people in radio ;-) And I thank you.
Over
73 de Christian G5DOC
_._
What about the ubiquitous half-wave coax dipole (yes, it’s a flowerpot) for 4m? They are always satisfying to build, and cost, well, nothing really.