Bit of a delayed entry. Had a quick run up the coast to assist Mum & Dad in Kalbarri (7hrs north of Perth) during lockdown. Took a small amount of gear and had a couple of good JS8 contacts. Found that my 40m link dipole only just fits across their back yard.
Just a few pics from a little while back. Probably a little more gear than I would usually take but I wanted to make sure my link dipole was still working (it does). Also discovered that 2nd hand 7Ah SLAB’s last about 15 seconds transmitting 10W JS8 with the ‘857.
So … it’s been a while. I tried (and failed) to get into portable operations by purchasing a Xiegu X1M a while back. I quite enjoyed activating my first summit with a borrowed FT-817 and decided the X1M was going to be my personal entry. It seemed like the ideal compromise of weight, price, power and bands.
Sadly, the X1M wasn’t to be. After building & testing a link dipole it started developing a nasty noise on TX. It seemed to kick in if I overmodulated and then, later, it didn’t require any prompting. The receive side worked very well & I used it for SWL for a bit until it stopped doing that as well. Not being particularly dextrous I decided not to poke around the two circuit boards too much in case I made things worse.
Fast-forward a couple of years and it was time to think about this whole portable thing again. The FT-817 seemed to be the best option as I had developed a fondness for the borrowed version. Scarce as hen’s teeth second-hand it looked highly likely that the new FT-818 was going to be it. Saved money here & there until & got close until, unfortunately, the local retailer upped their price. That was it! I ducked onto the VK classifieds and found a FT-857 for sale locally … and right in my price range. The next day I was a proud owner. It’s a little bit heavier but still ultimately portable.
Let’s step back about 18 months or so. It’s solar-minimum-ish time & 10 watts just ‘aint cutting it (I’ve tried to learn Morse but it’s still a work in progress). I had been following the developments of WSPR for a while and now there was a new mode FT8 that operated on the same principles as WSPR. I was able to listen and spot but the license restrictions on Foundation callsigns were such that I could look but not touch. I was good with that. That was the whole idea of the way the licenses were tiered. It was great incentive to upgrade and further oneself. Just didn’t have time to get in and do it. The dream of a Standard call will remain just that for the time being.
Fast-forward to 2019/2020 and the WIA has successfully advised the ACMA to allow F calls to use digital modes and that it wouldn’t be bad thing. This caused a flurry of research into audio isolation interfaces, modulation, drive & methods of connecting radios to computers. All of a sudden my 10 watts was going to take me places. I had a play around with FT8 but it seemed a little too automated and, although I was assured by the manuals that I could, I wasn’t able to see how it would easily accommodate a good rag-chew. Sure enough, the vast majority of FT8 traffic is, while technically speaking, QSO’s, there’s no, “How’s things, haven’t heard you on for ages, how’s the weather over there?”, sort of thing. Enter JS8.
I had been following Julian, OH8STN, for a while on a couple of different social media platforms. He has an amazing amount of experience in portable operations and his preferred digital mode is JS8Call. Jordan Sherer, KN4CRD, had re-purposed the FT8 codec and made it more QSO-friendly. JS8 is a very lightweight programme that can reliably decode digital signals down as far as -20dB SNR in 4 speeds between 8 & 40 words per minute (depending on conditions). After seeing Julian’s videos on JS8 development and use, I was hooked.
JS8 and FT-857
Finally got my audio interface to work. It’s a very basic circuit that isolates the TX side. I used an old PS2 mouse cable and a surplus 3.5mm – 3.5mm stereo cable that comes with a lot of PC & KVM extender kits. Also seen in the pic below is my well-dodgy QRP dummy load. The image on the screen is a VNC session from the shack laptop. I was listening to the shack radio (IC-718) through the dummy load.
The next steps will be sorting out portable power for the FT-857. A fantastic reference for this is Andrew’s (VK1AD) blog. He’s done a lot or research into ‘857 power requirements as well as creating some great resources for portable equipment users generally. I don’t think my idea of a second-hand 7AH SLAB is going to cut it somehow.
Thanks to the online resources of the above-mentioned, Ian (VK5CZ) who’s semi-regular contacts keep me inspired & motivated and VK6AXB for the constant leg-ups and astounding knowledge of all things radio.
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The VK6 SoTA programme has started and thanks goes out to everyone who made it possible.
Anxious to get started, I thought a trip up to Mt Dale on my day off would be a great beginning. I have been here a few times before, once camping and a few other times chasing thunderstorms. At one time I would have said that I knew the way through the hills like the back of my hand … but it’s been a while.
A FT-817 was lent to me again by on old friend, until I can get my hands on a X1M, and headed up the hill same way I always remembered. The only real problem, apart from HF conditions, was the road I had always used had been blocked by Water Corporation. For future reference, this is Pickering Brook Road out towards the old Barton’s Mill prison farm.
The best access from the north is on Ashendon Road that runs off Mundaring Weir Road. It is all-weather dirt and is quite well used and subject to quite large potholes that can catch out the unwary. There were a few nasty washaways, narrow but deep, just remember not to be still braking hard when the front wheels go in. A section of Dale Road was also inundated and had water still flowing over it. This bit was quite slippery but the Prado ambled through it happily. I have done the same section many times in a Holden Barina, so don’t be fazed.
Southern access onto Ashendon Road from Brookton Highway is also available. This means less time on dirt roads but greater travelling time from the bulk of the metro area.
There is a small picnic/camping area on the right hand side just before the the final ascent. I assume this is where campers and walkers stay on this leg of the Bibbulmun Track. I’ve never really had a look around there apart from noticing some picnic tables in the scrub.
Once at the summit I opted for a ‘walk out/walk in’ approach. I could park quite close to the summit but to comply with activation rules I walked outside the activation zone (quite a lot, as it turned out, due to a laggy GPS) and walked back in, carrying all my gear for the activation. I tethered the squid pole to a handy post, placed all the other gear on a small retaining wall, did a Goat spot and started calling. One thing I did notice was the occasional data burst of some kind from the repeater tower on the summit. It only lasted about a second at a time but was quite intermittent and more noticeable on higher frequencies.
After an initial flurry of contacts on 40m I tried 15m. Sadly conditions were not conducive to interstellar QRP contacts apart from VK3OHM, who was 5/8 with QSB to me but I was unable to complete the contact. I guess I’ll need to upgrade & join the 20m brigade.
Thanks to all who answered the call on SOTAWatch and the various forums. Looking forward to the next one. Apologies to those on 15m but I had to head back to Perth to pick up the kids from school.
A friend has kindly lent me his FT-817 and I decided to have a quick play late on Sunday afternoon. 5W, a random wire and a manual tuner works well. Seems to be a lot more sensitive on receive than the Barrett 950. Might just be the lack of bulk QRM from the home dipole that makes the difference.
Took my completed link dipole up a local sand dune to play today. The conditions were lousy but still managed a couple of local contacts. Nice and quiet up there too, even if it’s only a couple of hundred metres from suburbia. I was thinking of going fully portable but the Barrett 950 is not ideal, too many parts and fairly power hungry. It really does prefer to be mobile. Still, a pleasant afternoon mucking about with radios.
Can just see the city skyline on the horizon and through the smoke.
Weather and other factors finally conspired to allow me to work on my portable dipole. The tune on it went way out on 40m after the top section of the squid pole snapped. A quick consult with an old friend and it was suggested that ground effect plays a larger part in dipole function than I was aware. He suggested shortening the legs if the dipole by up to a metre! Bearing in mind that my previous experience was with higher frequencies (11m and above) I thought this was quite excessive. I kept shortening to instruction and found that with a feed point at 5.4m and the legs of the inverted V terminating at .75m above ground level, it had to shorten the legs by 1.2m.
Now I’m aware of this it will be easier to tune antennas in the field simply by doubling the wires back on themselves and using a little insulation tape or, if a semi-permanent fix is required, then a cable tie or two.
I live in WA, have an ‘F’ call, am interested in Summits on The Air and we appear to be experiencing one of the biggest nulls on 40m in recent history.
This does not mean that I need to miss out.
I recently discovered a Software Driven Radio (actually 4) that can be driven via a web user interface in Melbourne. From here I have been able to enjoy listening to SOTA pileups.
I would like to thank Andy, VK3YT, for allowing us to have access to this technology. Sadly, I probably can’t get SWL points as I’m not at the receiver, but, for the record, here’s my brief log from last weekend.