I have constructed a mono band 28 MHz coaxial dipole (flowerpot antenna) for the southern hemisphere summer E season.
The 2nd and 3rd days of summer have shown promising results for the next two to three months. Whilst VK doesn’t have the ham operator population density as that found in the northern hemisphere, if you are patient, pick the right time for sporadic E to form and keep a close eye on Australia’s space weather forecast, you can qualify a summit on 10m with four unique QSOs.
The SOTA activator map shows the antenna has a good omnidirectional radiation pattern working VK4, VK5, VK7 and ZL out to 2100 km. SOTA maps acknowledged.
So far three activations using this 10m antenna, all three qualified on 10m, including a recent HEMA activation. Audio reports are good and no sign of RF feedback
I constructed this antenna and tested it on a SOTA activation yesterday. I didn’t stay on 10m long due to contest QRM but managed amongst others a S2S QSO with Stavros SV2RUJ/P in Greece.
Excellent video as always. Although my 40m EFHW has brought in some good 10m DX for me on Sota summits I’ve had a few good contacts with that 10m ‘Flower pot’ from the garden. As the wx warms up I’ll be using it more often on the mountaints. I used the tube from an old silicone dispenser for the coil which is 50mm diameter and ‘free’ once you’ve finished the tube . Good to hear Nick, Dave, Phil and Mick calling in to you.
I’ve read reports of people working things using all sorts of antennas on 10m.
From my home QTH at the moment I’ve worked a local SOTA, one in Malta but mainly all I hear is Greece. As propagation changes and more Sporadic E is on 10m I expect Activators and Chasers to have a blast and log plenty.
Also, Natalie and I are in Anglesey for a week in June staying near Holyhead Mountain. There will be some SOTA activations so keep an eye on the Alerts. Hope to work you then.
Hi
I was out yesterday also, on a boggy G/WB-020. Despairing of finding a free frequency on any HF band I decided to stay on 10M and join in the contest. 22 logged in 40 minutes, including USA and Caribbean. The flowerpot works a treat !
Just wanted to give thanks for the 10m flower pot instructions. Used it on my initial activation yesterday. very first QSO was an S2S with ZL and also a contact in Japan. Instructions were easy to follow and antenna worked really well. Thanks again
Hi Chris, great to see you back, look forward to the future videos. You might want to look at the web site of the designer of the Flower Pot antenna, John vk2zoi (SK, Jan 2021 ). Here is a link- Flower Pots – VK2ZOI.
The site is maintained by his radio club he was a member of (President for 30yrs).
I built a 10m flowerpot yesterday.
Self resonant coil is resonant on 28.1MHz.
Fits nicely on 6m pole with coil 700mm AGL.
Swr 1.6:1 28.0 to 28.2
Input impedance at 28.08MHz, 67 j20Ohms, swr 1.5:1
Coax below coil is “rf dead”
Easy to deploy.
If I built another, I would try equal top and braid section at 2510mm each, aiming to reduce the 67 Ohms a bit.
Looks like a useful activation antenna.
Just looking for a dry day now!
Since my last post I have had some success with the RG58 Flower Pot antenna including working Tom M1EYP/P on Lad Law G/SP-008 from G/SB-008 in Northumberland. However it has one drawback, it weighs in at 555grams.
I gave some thought to lightening the antenna by using RG174 coax. The antenna uses about 8m of cable and at 28MHz using RG174 incurs an additional loss of 0.6dB compared to the RG58. I also changed the former from plastic waste pipe to 0.5mm wall thickness glass fibre 50mm dia. tube. This combination weighs in at 181g, a substantial improvement. But does it work?
Yesterday I activated G/SB-007 and was fortunate to catch Tom, this time on G/SP-015. The reports were similar and the distance, a little further. I suggest that the RG174 cable is the way to go. At least my shoulders think so!
I resonated the coil on 28.1Mhz and the coil has 24.5 turns. The upper part of the dipole is 2400mm long and the coax lower section 2340mm. VSWR 1.2:1 at 28,2MHz.
Regards
David
G0EVV
PS I was also thinking that a 6m variant may be worth a try?
Good to hear from you again Andrew.
I have been using flowerpots for over 13 years now. Whilst Activating the 330 Wainwrights in the English lake District I made over 3000 qsos on 2m using the Flowerpot mounted in my rucksack.
Thank you for triggering my mind to try other bands on Sota.
So next week I will do the loss calcs for an RG174 6m variant and heat up my soldering iron.
Thank you
David
G0EVV
. Good to hear Nick, Dave, Phil and Mick calling in to you.
