Recently I changed my job.
Sadly this led to the loss of use of the wideband Discone antenna mounted for test purposes on the side of the old building, which I'd used for my TinyGS and LORA APRS igate.
I have got an iGate at my home, however I'm disappointed by it's woeful performance on the co-linear antenna I fitted in November last year, it requires further investigation when the weather improves!
First things first, an antenna is made up around an SMA connector, and given a tune-up using the Nano VNA. You can get rough dimensions from this great on-line calculator.
Next, I need to come up with a method to mount the antenna.
The plan is to mount the antenna on the top of a piece of 20mm electrical conduit, as a simple mast.
A slotted cylinder and locking ring is 3D printed. It's a bit on the thick side, as the first one I made was a bit thin, and split...
The slotted cylinder fits over the antenna radials, and secures it to the 20mm PVC conduit. As the cylinder is now so thick, it's a really snug fit, and the locking ring is not required.
The 3D model for the cylinder can be found here :
As I want to feed two receivers (one APRS, one TinyGS) I've fitted an LNA and a splitter (both procured from AliExpress). The LNA will overcome the losses in the splitter (especially as I ordered a 4 output splitter by mistake!). You can just see in this photo, that I coiled the coax around the PVC conduit. This type of thing is usually used as a choke balun. It's not really needed here, but was just a convenient way to tidy up the coax!
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| TinyGS |
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| LORA APRS |
Ionosphere can be found at https://github.com/cceremuga/ionosphere
It supports linux, mac os, windows, freebsd, and, of course, our Raspberry Pi. There's a handy script on the page for installing the software on a pi automatically.
There's some config to set, but it's quite straightforward.
Off to the attic!
The Base of the antenna can just been seen, sticking out of a redundant water tank.
Thankfully, my wifi reaches the attic, and all devices log on to their respective servers...
The two APRS iGates appear on the map ...
and TinyGS is working very well.... This picture was taken after a few days, you can see the increase in the numbers of packets received...
... including some well out of footprint! (Tropospheric ducting, perhaps?)
Sadly, neither my VHF or UHF APRS stations have captured anything yet, as there's not much traffic here... I'll update you on those as it goes ...
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ReplyDeleteYou're certainly in the right neck of the woods for ham radio, Andy!
ReplyDeleteI've found this Blog via your presence at Retro Tech UK 2024, where I was for the first time after discovering the event a few weeks beforehand. It's fitting that you should have brought up the theme of walking as I walked all the way to Ryton-on-Dunsmore, with the aid of an A to Z street atlas of Coventry dating way back to 1991, from Coventry railway station, travelling there from Belper. It nearly got me there, but I had to ask a couple of locals for directions when I'd finally reached Ryton-on-Dunsmore as the leisure centre was slightly outside the atlas's coverage.
It was quite good that I was there, for picking up an admittedly non-functioning ITT-KB Tiny Super, like I got for my twelfth birthday in the summer of 1973, for £8.00, a similar (functioning!) ITT Weekend Automatic for £20.00 plus a couple of records from the place in the corner near the public conveniences - 'På verdens tak' from 1974 by Kirsti Sparboe and Benny Borg and a 1955 single from The Modern Jazz Quartet. The 'Retro-spective' YouTube channel caught me at that stall!
I also have a rather more up-to-date A to Z street atlas of Cheltenham and Gloucester (2012), so I used that to follow your walk into Cheltenham, which always brings back so many memories, as that's where my adult life essentially began, with two short summer sessions as a digger at Crickley Hill in 1979 and 1980, staying at the former Civil Defence Centre in Ullenwood, off another Greenway Lane, plus the reunion picnics on Crickley Hill itself I attended, on and off, between 2011 and 2019, generally walking out there from Cheltenham Spa railway station and occasionally dropping off at the now-demolished Air Balloon pub in Birdlip after the reunions, where we'd very often go on those summer's evenings back in '79 and '80.
This July, as a sixty-third birthday present, my older brother has treated us both to a Saturday night stay at the Royal George Hotel in Birdlip, coinciding with this year's reunion and I'm hoping to drop by Ruby's in Birdlip, where I understand the picnic tables from the Air Balloon's Beer Garden have been re-located.
So thanks, Andy, for that walk and, who knows, we might meet up next year at Ryton-on-Dunsmore!
There's a lot of radio here, possibly something to do with a local government establishment. I never worked there (possibly due to a slightly misplaced youth, with regards to possible slight misuse of the RF spectrum). Did you see my retro tech youtube video? So nice to put faces to names. I came away with a couple of Panapets, a Ferguson TX9 portable, and picked up a camera tube from Jonjo. It was a great event. Next time you're here, drop me a line and we'll have a coffee.
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