Monday, April 29, 2019

Receiving Peter, VK3YE's 100 microwatt WSPR beacon

Prolific ham radio writer, Peter, VK3YE has put up a video about his attenuated WSPR beacon being picked up by a number of stations and happily I'm one of them. I'm VK2TPM by the way and am over 700km from Peter.

Another frequent receiver is Phil, VK7JJ, who gets amazing WSPR reception reports. The trick, of course, is low noise reception. I'm doing pretty well for a suburban block. Phil is on a property in Tasmania and has taken considerable steps to reduce noise.

Ross, VK1UN, makes a good point that with this much attenuation it might be that signal leakage is actually being transmitted rather than what goes through the attenuator.

I think that decodes from directly synthesised WSPR transmitters, as compared with audio modulated SSB transmitters, are easier.

Thanks for the contact Peter!

Thursday, April 25, 2019

WSPR receive antenna comparison

My normal 40m antenna here is in the back yard hanging between the house and a tree. Operating position is at the front of the house so a long run of co-ax is used. I've tried dipoles at the front of the house but they've always seemed more noisy - presumably because of the power lines in the street.

Yesterday I ran WSPR receive on both antennas and found just how amazingly more noisy the antenna at the front is than the normal one out the back.

The front antenna is reported as VK2TPM/1. As you can see, signal to noise ratio is consistently 13dB worse out the front. Now, these are different receivers but I doubt they would make that much difference. There is also a 3Hz difference in reported frequency.

Keen eyed observers might notice that I'm searching WSPRnet for "vk2tpm*", yes wildcards do work in some contexts. The app here is WSPR Watch.

Friday, April 19, 2019

Home again - after crossing Australia

A very enjoyable adventure. Being away, living in a van, helps me appreciate the comforts of home. This post is a collection of observations on the journey.

I slept in the van for about three out of every four nights.

TVs in motels often don’t have all the available channels. I auto retune them and find more. Perhaps a result of re-stacking?

There are people riding bicycles over the Nullarbor. The road is quite narrow and this seems very dangerous.

I saw two groups of vintage cars being driven. Beautifully restored.

There are large numbers of people towing caravans across Australia.

Nullarbor is Latin for no 4G coverage. Just kidding, it is Latin for no trees.

There are about four parts of the highway which are marked up as Flying Doctor emergency runways. You can pull off to the side if a plane lands.

Signs showing the distance to a service station also show the distance to the following service station so you can make a decision about whether you need to stop. The longest run I did between refuelling was 460km, I think the van would make 500km but I didn't test this.

Oncoming drivers will often raise a finger or make a peace sign, or wave, as you approach. I think it means that if you broke down they’d stop to help. Most truck drivers don’t bother but some trucks are aware of the effect they have on me as we pass and will pull way off to the side as they approach, I give them a friendly wave of thanks.

Google maps is superior to Apple maps in several ways. It has a lot more points of interest, particularly in the outback. Google maps seems to behave better when there’s no data, I guess it caches more. In Google maps, you can drag up from the bottom and do a “search along the route” to find petrol stations for example.

The Google maps search ahead feature makes odd choices about what to display, it shows the brand or name, the number of stars in Google reviews, and that it’s a “quick detour”, it does not show how much time to get there or the kilometres.

Motel rooms have a can of insect spray in the room.

Many small towns have FM stations. Larger ones have relays of ABC Radio National, News Radio and Local Radio. Sometimes the ABC relays are distorted and on one occasion the carrier was there but no audio. In most cases two FM stations are working, the horse racing station and the Christian propaganda station.

Australia is often called a “wide brown land” but my observation is that a lot of it is very red. In some places the earth is red, trees are red and green and the sky is deep blue.

During the trip I listened to some music but many podcasts which entertained and informed me. What a fantastic new media.

Not surprisingly I used up my monthly data allowance and the excess data fee is a high $10 per GB. On Telstra, I can buy data packs at a slightly cheaper rate but they will charge again in the following month. I've now learned that cancelling the data pack in the next month means you only get charged pro-rata which seems fair.

When data is scarce, it’s a new world. iOS lets me choose app by app what can use mobile data and I’ve turned off lots of apps. Free Wifi is very attractive but I’ve found it’s actually limited to 500MB and it’s easy to use this just downloading a few podcasts. Netflix downloads have been great.

I sleep a lot when living in the van. When it gets dark, it’s bed time although I spend hours tuning around on the broadcast band and particularly shortwave. When the sun comes up, I get up, make coffee and hit the road.

Listening to shortwave in a low noise environment, away from power lines, switching power supplies and plasma TVs is amazing.

There isn’t a lot of English on shortwave these days. China Plus is everywhere, a bit of Voice of America and a bit of BBC. I haven’t been able to receive Radio New Zealand International in the west so I guess it’s beamed at the Pacific. I really miss the Radio Australia inland shortwave service.

A shortwave broadcast from India talked about the anniversary of a masacre by the British, they reported the deaths as 1,000. The BBC covered the same story but reported 300 deaths.

China Plus sometimes refers to the “peaceful re-unification of Taiwan”.

My antenna is a dipole cut for 40m. It’s held up by a 6m squid pole tied on to the van. The wire is a figure 8 twin cable fed from the balanced output of my antenna tuner. I tied the ends onto any trees or bushes near by using brickie string.

I drive at about 100km per hour, the van gets much noisier at higher speeds and I think it’s more economical at this speed. Drivers approach at higher speeds and when it’s safe I indicate left and slow a little. After they pass they indicate left and then right briefly, I think this is a way of saying thanks.

The largest cost of the trip was petrol.

Some drivers are slow until there’s an overtaking lane and then they speed up.

There are cellular telephone towers on the Nullarbor but they’re not close enough for continuous coverage. There’s no 4G. When you get to one of these towers they are a sight to behold, the guyed tower is about 100m high and at the base are satellite dishes and solar panels.

Broken down cars can be seen at the side of the road. Recent ones have police tape on them, older ones are missing the tyres and are sometimes burnt out. Most have broken windscreens and I assume they’ve hit a kangaroo.

There are frequent skid marks on the road where a vehicle has hit the brakes. I guess these survive many years.

There are many museums in small towns and it's a great amusement to visit and see what's on show.

The most seen dead animal on the road is a Kangaroo. Signs warn of Kangaroos, cattle, camels and wombats. Leaving Broken Hill, heading west, there are a large number of goats but luckily goats walk away from oncoming cars rather than jumping in to their path.

On the way home I ran into a bit of a heatwave in northern South Australia. As I result I drove more than planned and have arrived a bit early.

I felt calm and happy during the journey. Watching the country change slowly is interesting. Tuning shortwave and the 40m amateur band was an absolute joy without all the noise heard in a city. Thanks to John VK2ASU and Kevin VK2KB for attempting contacts with me on several occasions.

It's good to be home again.

Thursday, April 11, 2019

Crossed the country - but waiting for parts

It's official, well from the WSPR Watch map, I've reached pretty much the western edge of Australia.

I was able to receive Kevin, VK2KB's WSPR beacon. We tried for an SSB contact but while I could hear John, VK2ASU, calling he couldn't hear me. We'll try again when I'm a bit closer.

As I mentioned in a Tech Head spot on RN Drive, it's quite a drive.

A few days were spent with old friends looking around Perth, which is a lovely place. I took the opportunity to drop in on the local GovHack folks.

On the way to Margaret River I heard a noise under the van that sounded rather like I'd run over a branch or something. Later I noticed it was rather difficult to steer, particularly while parking. Bridgetown has a few car service places and it was rather obvious (in retrospect) that a belt is missing.

It's the belt that drives the power steering. So, I'm checked in to the Hotel on the main street waiting for a replacement and I'm going to have the vehicle serviced on Friday.

Quite a nice little town with lots of local art on display and for sale. How about a miniature shed for the van?

While enjoying a cider at the bar downstairs I chatted with a bloke who works at the local Lithium mine which he tells me is the largest in the country and going really well presumably due to big demand for the metal for batteries. He said it's half owned by Chinese investors.

Responding to user feedback, I've done some updates to the WSPR Watch iOS app. In particular there were problems using the settings view on the smallest phones and iPads. I'm now looking in to decoding WSPR on an iOS device (you can transmit in WSPR Watch as of a few months ago).

Saturday, April 06, 2019

Ultra low noise HF radio in the outback

One thing I've been particularly looking forward to is listening to HF radio devoid of all the interference we get in the cities.

My favourite free camp site so far is the one at Fraser Range. There’s a waterhole here in the rock and you can park overlooking a gorge. I chose a spot with some small trees so a dipole for 40m could be set up.

The noise level was astonishingly low. The only sounds were distant lightning crashes.

I carry a 6m squid pole to hold up a light weight balun seen here. The ends of the dipole are strung up on trees.

Tuning around I heard mostly Japanese hams but also europeans and a few east coast Australians. I brought a complete setup for WSPR reception and transmission.

The HP Stream laptop is handy in that it has very long battery life, 7 hours or so, and I've built a voltage boost charger circuit to give it the 19V it wants from my 12V supply.

I decoded up to 11 unique stations in a 2 minute WSPR slot. Here's a sample:

Transmit also worked well and I was spotted around the globe. At first I ran 5W but turned it down to 1W with almost the same result. Here's a display in WSPR Watch.

There are some noise sources in the van. The fridge creates a racket when it's running, the solar charge controller makes noise and the LED lighting that's built in is terrible. My little laptop charge booster unsurprisingly is terrible. I'm running the radio from an SLA battery but even so the fridge needs to be off for best results.

Crossing the Nullabor

It’s a long stretch of paved road through country devoid of trees. There is scrub and sometimes quite large bushes but never any shade. When I crossed it was hot and when stopped the flies are very persistent.

My anxiety about petrol was not warranted. The van’s range is about 500km and generally there is fuel every 200km. There are signs letting you know how far it is to the next fuel. A tail wind certainly helped with fuel consumption but I topped up at every opportunity.

The views of the great Australian bite are spectacular and well worth stopping for. It's an amazing contrast to the desert just next to it.

Often there was no mobile reception. I scanned the FM, AM and Shortwave bands and the only station I could hear was a Chinese shortwave station.

Australia is a big country and it’s a great pleasure to have the opportunity to drive across it.

Wednesday, April 03, 2019

Broken Hill to Ceduna

Broken Hill is not a bad place to get car repairs done. There's lots to see although sometimes I felt like I was paying an entry fee to go in to a shop.

The place has both wind and solar power to quite a big extent. Here's a tiny bit of the 43MW solar collector.

After Broken Hill I visited Peterborough, which is a nice town, passed through Port Augusta.

The van is going well and I'm gradually adjusting the layout and improving my van cooking. Signature dish here:

Stayed a night at Kimba.

I set up the ham radio gear but regrettably there was a very high noise level from a power line running through the camp site.

Now I'm at Ceduna, which is a lovely place. Here's the main beach.

The caravan park in the town is super crowded so I'm further south at Shelly Beach which is lovely.

Once again, the 40m dipole is up and here the noise level is very low. It's mid-afternoon and I'm receiving WSPR well and am being heard. I'm going to have a better shot at it closer to dusk.

As you can see from the WSPR map, I'm half way to Perth.