Wednesday, 10 August 2016

WSPR Stats

After looking at how many people are using DMR, I thought I'd look into how many people were using one of my favourite modes - WSPR. As almost every reception report is logged and displayed online, this is quite easy.
I got the data from KB9AMG's site which shows "2 way" reception reports. These are where both stations have logged reception of each other and uploaded this to the WSPR spots database, rather than actually having a 2 way QSO. This is a pretty reliable way of counting all stations who were active, removing any false decodes.
I combined the data from the months of May, June and July 2016.

In 3 months, in England, 493 stations were active on WSPR.
Breakdown by callsign type:
2E0 = 45
2E1 = 3
G0 = 56
G1 = 21
G2 = 1
G3 = 50
G4 = 91
G6 = 20
G7 = 32
G8 = 29
M0 = 103
M1 = 12
M3 = 10
M5 = 4
M6 = 16

Compared to the figures for DMR (see the last blog post), there is much less interest from Foundation and Intermediate licence holders. As with DMR, the M0 callsigns are the most common (21%, compared to 16% of DMR), but G4s are not far behind at 18%, which is much higher than their 10% share of DMR registrations.

Worldwide, there were a total of 3990 stations active in the 3 months on WSPR. Most of these were only active in one of the 3 months
Breakdown by months active:
3 = 871 (22%)
2 = 935
1 = 2184

Where are all the G0s? Shouldn't there be at least as many as G4s (G0 callsign range was almost fully issued) and M0s (still not fully issued)?

Monday, 8 August 2016

DMR Stats

Had a look at how many people are registered on the DMR MARC database, from the UK. This gives a rough idea of how many people have ever transmitted on a DMR radio in the amateur bands. There's nothing stopping you setting the radio ID to anything you want, especially on simplex, but I think most people would register.

Total DMR IDs:
19th May 2016 = 3641
8th August 2016 = 4035
That's an increase of about 10% in the last 71 days (or 6 new IDs per day). It's still only around 5% of the total UK amateur licences. But 4000 is a very large number if you compare it with say the number of people entering a VHF contest or logging Summits On The Air contacts in the database.
It will be interesting to see how the total increases over time, 

Breakdown by callsign type (England only)
Total England = 3353
2E0 = 496
2E1 = 38
G0 = 306
G1 = 185
G2 = 7
G3 = 92
G4 = 331
G5 = 4
G6 = 182
G7 = 225
G8 = 185
M0 = 533
M1 = 124
M3 = 163
M5 = 12
M6 = 470

That may or may not be a reflection of how many of each callsign type are active on the air in general, as newly licenced amateurs could be more attracted to modern tech gadgets rather than traditional equipment.

Friday, 5 August 2016

Two Decades of M1AVV

Tomorrow will be the 20th anniversary of me having an amateur radio licence. The date on my licence was 6th August 1996 but it wasn't till 18 days later I knew my callsign. Partly because I was on holiday and the licence was on the doormat when I got home, but stuff just took so much longer before we all had internet access. 

I got the licence aged 15, so I'm "only" 35 now.
My first amateur transceiver was a Rexon RL102 144MHz handheld, and at the time was the cheapest proper handie (it was just under £100 but there were very low power radios for a bit less). Nowadays something of that spec would be about £20 from Baofeng, but it was pretty good at the time.
Things have changed a bit in the last 20 years, there were digital modes but most packet was through bulletin boards rather than the unconnected APRS messaging used now. I think repeater use has gone down (at least on the analogue ones), with simplex FM use maybe increasing in some areas with people coming off CB. There were a lot more people on repeaters actually mobile driving to/from work.
Back in '96 you didn't have to worry about what CTCSS tone to use (1750hz toneburst always worked), narrow deviation (nobody used the 12.5khz channels) and definitely no talkgroups. But even now I'm not keen on asking people to go to a 12.5khz offset channel on 145MHz simplex, I still don't bother programming them as memories, so feel free to talk about me on 145.5875 or something.
In the 20 years, I've probably had a contact with someone at least once in every single month, and the longest I've gone without having a radio switched on receiving amateur frequencies will be about a week (well it was our honeymoon!). I always think I can make more of an effort in answering or making calls though.
I was M3ICQ for 2 years (did the Foundation morse test to get on HF as an M3 in 2002) and also KC0PUZ for 10 years (did the US exam at Harrogate rally in 2003, licences expire after 10 years and never renewed it).

Tuesday, 19 July 2016

Bigland Barrow

A visit to Bigland Barrow, one of Wainwright's Outlying Fells (WOTA LDO-112).
I'd set off this morning to do Gummer's How (SOTA G/LD-050) but the traffic slowed to a halt at Haverthwaite so I diverted to Bigland Hall and walked to Bigland Barrow instead.
This is one of my nearest Outlying Fells (or any Wainwright) and is only a short walk.
Took the FT-817 and W50 antenna, which was a change for this summit as it's usually somewhere I just want a quick walk to and only need the one contact to qualify for WOTA.
Today I made 8 QSOs, including G0HIO/P on Harter Fell SOTA G/LD-028.

View of almost the entire walk from where I parked

 A few local summits to the west

"Wartime relic, now in a state of disrepair", which is useful for increasing the antenna height

I should have been here

Another Outlying Fell, Newton Fell North is around 3km to the east. This is used as a Wi-Fi link site and one of the channels was strong enough to be picked up on my phone (SSID NF-SH, channel 116, 5580MHz) as Bigland Barrow is almost directly in line with the beam.

Sunday, 10 July 2016

Billinge Hill

Friday's activation of Billinge Hill SOTA G/SP-017
Used the Alinco handheld and 40cm whip. Not as bad for overload from all the masts as I thought it would be, even on 145MHz any interference was gone at the lowest attenuator setting (about 3dB?) so it wasn't really a problem.
Most of the transmitters on Billinge are between 163 and 183 MHz, so some way from the 2m amateur band, and on the mast furthest from the summit. Apart from Airwave TETRA around 393MHz, I don't think there are any UHF transmitters up there any more.
I made 8 QSOs from Billinge Hill, 7 on 145MHz and one on 433MHz. The furthest was G4ING who was in Hyde, around 42km away, also only on a handheld.

Summit of Billinge Hill

View towards Winter Hill

Remains of something

4 masts on Billinge Hill

Cropped from my phone camera so not the best quality, this is the one with the broadcast antennas on, and looks like it would have had emergency services pre-Airwave. About halfway up are the DAB yagis pointing towards Liverpool. Wish FM 102.4 looks like 2 crossed yagis, one towards Wigan and the other towards St Helens. The other mast is probably from the analogue mobile phone days.

Very busy mast with most of the high VHF stuff on. Furthest from the summit.

Apart from the microwave dishes, only a couple of low VHF dipoles. These might not even be used any more.

On the way here, I stopped at the slightly lower Ashurst Beacon, further north on the other side of the M58. This would be a much better place to play radio from if not after the SOTA activation, with a large car park and land open to the public. There are two viewpoints with car parks, about 2km apart on the ridge, one is better for the north, the other for the south.
Here is the trigpoint at the south viewpoint (168 metres)

Wednesday, 1 June 2016

Brant Fell and New Car

On Saturday I was at Windermere in the morning so I had a quick walk up Brant Fell (WOTA LDO-113) on the way home. Just took the Alinco handheld up there and made 2 contacts, M0AYB/P who was on the way up St Sunday Crag from Patterdale, and M0LKB at Ulverston.
Parked at SD413961 on the road to the east of the fell, where there is a parking space at the start of the footpath.

On Thursday I picked up the new(ish) car, a Nissan Note N-Tec 1.4 petrol. It has built in satnav, Bluetooth and USB music playback.
No less than 3 12v sockets - one below the dash, one behind the front seats and one in the boot. Also some good places to keep a radio out of the way.

Fixing the FT-8900 head unit to a phone holder. Screwed back together after putting cable ties through.

Sunday, 1 May 2016

Car Electrics

In the last few weeks I'd been having some trouble with the Yaesu FT-8900 radio which I have in the car. When switching it on, it displays the DC voltage and I'd noticed that it was very low. Under 11v with engine off. I've got the FT-8900 wired up the way that every instruction manual ever written tells you not to - through a cigar lighter plug. This is not usually a problem, I've never had a radio connected any other way in the car and never used over 20 watts mobile from the FT-8900. Also, the radio is transmitting APRS while I'm driving, with around a 1% duty cycle and 20 watts.
At first I thought the car battery was not charging and would soon be completely dead, but I did a check with the engine running and the voltage did go up, so the alternator was OK. The voltage while charging did seem a bit low, maybe 12.8v. This was while I had the radio on receive, but when switching it off, the voltage went up to the normal 14-ish. That's a big voltage drop for something drawing under 1 amp on receive. I checked the voltage drop between the negative wire on the radio and the car body, and it was very low.

It turned out the connection between the lighter plug and the socket was bad, because there was something that looked like a burn mark on the centre contact of the socket. Something had probably knocked the plug out slightly and the resistance had increased.
I cleaned the contacts up and the total voltage drop with 20 watts transmit power is around 0.3v (including the wiring from the battery).
 With the engine running, there must have just been enough voltage at the FT-8900 to let it transmit (or at least look like it was - nobody picks me up on APRS round here anyway!). I'm guessing below about 9v the radio will shut down.

One other thing I learned from all this is that the Nissan Juke (and probably lots of other cars) doesn't keep the battery charging all the time when the engine is running. This is something I'd never thought of before, normally you would leave the engine running if you wanted to power something that might drain the battery - like a high power transmitter.
After starting the car, the alternator is connected to the battery, but once the battery voltage reaches a certain value, it cuts off when the car thinks it is fully charged. Now this is a problem because I don't think the "fully charged" voltage is really fully charged, and it just replaces what energy was used the last time the car was started, and then cuts off. Searching online, I found that this is a known issue with certain Nissan Jukes and the batteries never charge properly. It also effects add-on lights which detect the battery voltage to switch on when the engine is running. Putting a load on the battery (the headlights usually work) can switch the alternator back onto the battery as the car sees a voltage drop and thinks the battery needs charging.

Monitoring battery voltage (engine stopped) with a CellLog 8S

Wiring to radio and APRS tracker. The FT-8900 cable is soldered directly inside the 3-way splitter. The APRS tracker is on the lighter plug, so I can disconnect it when not wanting to transmit data.