Saturday, 17 December 2011

Flex-1500

Ordered a Flex-1500 QRP Software Defined Radio yesterday.
Since I mostly use low power and digital modes from home, I thought I'd try something different to the usual HF transceiver. I'll use it with my LDG auto ATU.

Saturday, 10 December 2011

PC Monitor

I've got PC Monitor installed on my main computer at home, which lets me check on running processes, event logs and hardware while I'm out of the house, using an Android app on my phone (also available for iOS and Windows).
It also lets me stop processes and shut down the PC, which is useful if anything has gone wrong and needs stopping.
The radio can be shut down automatically with the PC using one of the "standby saver" 8 way socket boards, which turns off all the slave sockets when the master socket current drops.
When I tried to put the PC to sleep with WSPR running, on waking up WSPR started transmitting and receiving at the same time, so probably not a good idea to remotely put a PC to sleep if its in the middle of doing something.

Got a RF Explorer (240 - 960 MHz handheld spectrum analyser) as an early Xmas present. One small problem with it is that the frequency displayed is about 40KHz too low, but apart from that it's a really good piece of kit.

Tuesday, 6 December 2011

2m Contest

Made a few QSOs in the RSGB 2m activity contest tonight, getting 263 points. At the moment, looking at the claimed scores table I'm second to last but don't expect to get much being vertically polarised.
I got locked out of my car earlier tonight after parking too close to a local amateur who was using 433.550 MHz, the remote control wouldn't work while he was transmitting. The car next to me (also a Vauxhall) was being affected too, the owner was trying to get it to open. I've had this problem in the past and even if I use the key in the door, the alarm sounds as soon as I turn the ignition.
At least it's not a 70cm repeater transmitting for hours at a time.

Saturday, 8 October 2011

440 MHz data

The mobitex data network just above 440MHz (440.4625, 440.4875 etc.) seems to have been switched off completely. All the sites using the 453 MHz channels (453.2125 etc.) went off a while ago, leaving a few of the 440 MHz sites going.
They were useful as 'beacons' for testing antennas.
A recording of one of them

The frequencies that were in use around here were:
440.4125 Barrow Town Hall
453.2125 Langthwaite (Lancaster)
453.2625 Blackpool
440.4625 Windy Harbour (Brinscall, Preston)
440.4875 Billinge Hill
453.1375 Blackburn
453.3375 Hameldon Hill
453.3875 Waddington Fell, Clitheroe
453.2625 Sedbergh TV Mast? (or was it from the mast at Gatebeck?)
453.2125 Penrith Beacon
440.0875 Whitehaven TV Mast (moved from 440.0125)
453.3625 Great Orme, Llandudno
440.1375 Llangollen BBC FM mast
440.2625 Heswall, Wirral
453.1375 Carlisle
453.3125 Shap Fells
453.3625 Hazelshaw Hill, Dumfries

Saturday, 17 September 2011

Comparing 20m antennas

Solarcon A99 vs 10m long end fed wire (sloping down from base of A99).



A99 is 6dB down on transmit and 6dB up on receive (as long as noise level and M6AYY's antenna stayed the same). Both tests were done around the same time of day and the distance is short enough to make sure the propagation isn't going to change.

The SWR without a tuner of the A99 is very high (>5:1) but the LDG AT-7000 autotuner handles it OK.







Thursday, 15 September 2011

Windows 8



Installed the Developer Preview of Windows 8 tonight. Apart from the screen resolution being limited to non-widescreen settings of 800x600, 1024x768, 1152x864 and 1280x1024 (none of which will scale up to the full size of my monitor, which is 1920x1080), everything so far has worked the same as in Windows 7.

I've tried installing some of my regularly used software and it has all worked. One program needed .NET but Windows downloaded it automatically.
The usual desktop and Windows Explorer are there behind the new tiled UI, and work mostly the same.

At the moment I'm running WSPR 2.0 and it's definitely transmitting and receiving somewhere so the sound card and serial port are working.
But will Windows ever have PDF support or have single-click turned on by default (it's only been available for 14 years)?

Holmfirth on 21MHz WSPR tonight (IO93CN, 111Km).

Monday, 12 September 2011

20m WSPR

Some more 14 MHz WSPR reports by:
G0GSJ - Barrow (<5km)
G4FUI - Penrith (68km)
G0BZB - Newcastle (144km)
Sometimes I was receiving a "ghost" signal from G0GSJ 100Hz away, about 34dB below the main one. Maybe some distortion in the transmitting computer's sound card or in the transmitter.
The same thing happened once on my transmission.

Tuesday, 6 September 2011

Barrow to Kirkby on 14 MHz

On 14 MHz WSPR:
M6AYY in Kirkby In Furness (IO84JF, about 14Km away)
My signal report -17dB S/N (10 watts)
His signal report -12dB S/N (5 watts)
And on the 7th September, M6AYY received me at -27dB S/N on 10 MHz WSPR. At exactly the same time (20:56 UTC), I got to W1BW at -18dB (FN42HL).

Other recent interesting ones are:
G1NXS on 14 MHz in IO83RK (Warrington)
M0RBY on 21 MHz in IO94DF (Masham, North Yorkshire)
G4OEU on 14 MHz in IO84XX (Hexham)
MW3DAO on 14 MHz in IO72XW (Porthmadog)

Monday, 29 August 2011

Watch Hill

After 9 years of SOTA, I worked another new Lake District summit, Watch Hill G/LD-054.
This takes my chaser uniques total to 183 summits. I'd activated Watch Hill once, in 2004 and wouldn't have expected to get anywhere in the south of Cumbria on 2m FM. But I made a contact with Phil G1OPV who was there while I was mobile on Walney Island. For those hard to reach northern Lake District summits, Walney is a good place as there is a clear path as far as the Scafell Pike/Great Gable/Pillar area.

Last night I spoke to M6AYY who was portable on Burney Fell near Kirkby.



Wednesday, 29 June 2011

USB Power Supply


110v - 5v USB power supply

US Broadcast Query

To find the transmitter details for a broadcast station in the USA, use this URL
http://transition.fcc.gov/fcc-bin/fmq?call=WTMP (replace WTMP with your station letters), or replace 'fmq' with 'amq' for an AM station.

Some differences between US and UK broadcasters:
Anything below 10KW ERP is a small station
FM channels are always spaced 200KHz, e.g. 88.1, 88.3, 107.7, 107.9 so there is no real overlap between adjacent channels. Stations in the same city are usually spaced 800 KHz.
AM channels are 10KHz spaced, and the band goes up to 1700KHz

Florida Log

List of WSPR reports I got while in Florida (Google Docs)
A total of 141 stations, best DX was 4X1RF in Israel (KM72LLinkLinkS) on 14 MHz
56 grid squares in the USA (Map of grid squares)
Spreadsheet to record US grid squares
29 US States
15 stations in the UK
I only received one station as the power supply was putting out so much noise. The noise was that bad, it was coming in through the ATU or FT-817's power socket, there was about S7 of noise even when the antenna coax was unplugged.

Now everything is packed up ready to go home tomorrow.
Round here, there are public safety and business radio users on the 850 and 935 MHz bands (both analogue and digital trunked systems).
East Central Florida Scanner Page

AM Logbook - list of all USA AM broadcast stations, with downloadable Excel spreadsheet
Florida Low Power Radio Stations - listing of past and present Part 15/Travellers Info/Pirate stations in Florida

Friday, 17 June 2011

KC0PUZ

Set up the HF station here in Davenport, Florida, using a horizontal wire in the garage, fed with a "long wire balun" and LDG Z-11 auto ATU.

At the moment I can hear nothing because of the very noisy switch mode PSU which I brought (a 4A 12v PSU, the kind used for a small LCD TV). But on transmit, these were my first reports:

The locator is EL98DG. I was surprised I got as many reports into Europe.
I've also got reports on 10 and 18 MHz around the USA.
The PC's clock is set using a USB GPS receiver, which works inside the garage. The software I'm using to set the clock from GPS is GPS Time And Test

Wednesday, 15 June 2011

USA

Travelling to Florida tomorrow, taking FT817 with me for some HF operation, probably trying WSPR. I'll be using my US callsign KC0PUZ (took their exams in the UK).
At the airport Travelodge there's a charge for using their WiFi, through a login page, but the Google Mail and Maps Android apps on my phone still connected without signing in.

Saturday, 30 April 2011

Samsung N150

My Samsung N150 Plus netbook (Atom N550 1.5 GHz dual core, 1GB RAM, Windows 7 Starter)
wPrime benchmark. The Acer Timeline X is no more after drinking a cup of tea. I got a Samsung external DVD writer to go with it, and 4GB of RAM.



Benchmark run while on mains power.

Faster than my old Philips 11NB5800 laptop (72 seconds) and Athlon 64 3200 desktop (77 seconds). Faster than a Samsung N130 single core Atom netbook (130 seconds).

Although it's a dual core processor, it appears as 4 to Windows. Some older software (like MP3Gain) will only run on a single processor so never use more than 25% CPU.

The clock can only be synced with a time server when running as Administrator. That's what I was doing wrong. Once About Time is run as Administrator, it's OK.

Wednesday, 27 April 2011

SRC 9:1 UnUn


SWR plot of Snowdonia Radio Company 9:1 UnUn, with about 7.5m of wire on a 5m fishing pole. The wire was coiled loosely round the bottom half of the pole to fit the extra length.
Fed with about 5m of RG58 coax, and no earth (except for grounding through radio power cable to car body).

Compare that to my own end fed half wave for 14 MHz which I have at home, using a similar transformer:

The basic SWR curve looks the same but there are some other resonant frequencies below 14 MHz where the SWR is not so bad. This might be because the wire is going across the back yard, close to buildings and telephone wires (also radiation from the coax). I shouldn't really be able to operate on 3.5 and 7 MHz with it but it works OK with a tuner.
Do "magic" short antennas like transformer fed wires/verticals just couple into other wiring when used at home?

Rooted my HTC Hero Android phone (Universal Androot) so the time can be synchronised with an NTP server. It's now accurate enough to be used as a WSPR beacon. Set up an alarm clock to play a recording of the correct WSPR tones at a certain time. Even if I'm away from network coverage, the time stays within a second as long as I've synced it in the last day.
Better than my new Samsung N150 netbook, which always says the clock is 5 seconds off when synchronising over NTP, but then sets the clock with a 5 second error.

Sunday, 10 April 2011

Icom CAT/data modes cable

I bought a data cable for Icom HF transceivers from the Blackpool rally today. It's something like the Icom IC-Cable-8 (cable 8 on this page).
The cable I made myself used the 6-pin mini-DIN socket on the IC-7000 but this one uses the 13-pin accessory socket and the 3.5mm jack (CAT interface). This replaces separate CAT and PTT/audio cables, freeing up a serial port.
PTT is possible via both CAT and serial port (RTS line). When using the 6-pin socket, there was no transmitted audio if CAT was used to key the radio (so there is no need for the hardware PTT circuit anyway). This doesn't happen with the 13-pin socket but there is one problem, the microphone sockets aren't disconnected. So when operating data modes using this cable, the mic gain needs to be turned to 0. If there is someone keying up with no modulation then it's probably me forgotten to turn the mic gain back up for voice.
The level of the PC Line Out also needed to be turned up from 10 (using my 6-pin cable), to 25 (using the 13-pin cable) to get the same output power.
I also got a Snowdonia Radio Company 9:1 Unun

Sunday, 3 April 2011

Distance between OS grid points

Online calculator of distance between 2 OS grid reference points

Saturday, 2 April 2011

Chagos

Just had both tx and rx wspr reports with vq9jd in Chagos Islands on 28mhz.10m is open to australia at the moment too. Chagos is in the Indian Ocean, about 10000km from the UK

Thursday, 31 March 2011

Springer

Got a 'Springer' CB antenna for the car. It's even in red to match the car.
Length 155cm, coil length 15cm, whip 136cm.
I thought I'd have to cut some off to use it on 29 MHz but when I tried it on a magmount it was resonant at 28.680 MHz, so it's just the right length to cover (UK) CB and the 10m ham band. Why such a high frequency? Maybe just where it is on the car or the magmount I used wasn't really big enough.

28 MHz is noisy, even when driving round, until you get about 100 metres away from the nearest house.

Friday, 11 March 2011

SWR plots for new car

Here are the 2m and 70cm SWR plots for the Nagoya NL-77B dual bander on the new car. This is with a small Sirio magmount towards the back of the car nearside. There is less than a metre between the dual bander and the broadcast antenna.
For some reason the Nagoya doesn't give a very good SWR on 145 MHz, this was the same on the old car and with a different magmount. It's under 2:1 though.
At UHF though, it's very good if a bit high in frequency, there aren't the usual reflections on the coax, this might be to do with the magmount and coax being quite new.

Saturday, 5 March 2011

New Car

Some photos of the new mobile set up in Vauxhall Meriva VXR. I've not put the APRS tracker in yet but that should be able to go back on its sticky mat.
Yaesu FT-8900 main unit on passenger side. CRT extension speaker.


FT-8900 front panel fixed to air vent using some old air fresheners and clothes pegs. The CD player will play MP3 discs.


Nagoya NL-77B 2m/70cm mobile antenna on magmount

Thursday, 3 March 2011

Kirkby Moor

Activated Kirkby Moor (SOTA G/LD-049) on Sunday 27th February.
Used Alinco handheld on 2m and Wouxun handheld on 4m, with Garex whip. Summit to Summit with Alex G7RNX/P who was on Cracoe Fell (SOTA G/NP-032).

Soldered a new PL-259 plug on my 2m/70cm antenna coax at home tonight, because the weight of the LMR400 coax had snapped the inside of the plug (the brown insulator bit). I only noticed when I unscrewed the plug and the centre pin stayed in the radio.

For testing serial port radio interfaces, try ComTest, which can be used to control the DTR and RTS lines on your serial port. The DOS/Windows MODE command is supposed to switch DTR and RTS but when I tried in in Windows XP, nothing happened.

Sunday, 13 February 2011

Shining Tor

Shining Tor SOTA G/SP-004
Friday 11th February
FT-817 into dual band mobile antenna. Also made 3 QSOs on my Wouxun 70MHz handheld.
Did this summit while on the way to Derby (carried on through Buxton and along the A6 into Derby)
It had started to get dark while at the summit (after 5pm) and was raining.

Thursday, 10 February 2011

SSTV

Some SSTV images received today on 14.230







Sunday, 6 February 2011

WSPR Stats

Site with WSPR stats for the last month, sorted by grid square, top spotter etc.
Overall in the world I was 187th out of 1856 WSPR spotters, with 341 stations received.
I was top spotter in IO84 grid square in January, out of 6 people. I'm also the top spotter with an M1 callsign (there are 9 of us).
I've been sending spots to PSK Reporter a bit too, mostly on 80 and 40m PSK31, using Digital Master 780.
It's interesting to look at PSK Reporter to see who is active locally, on HF, especially with the data modes it's not easy to tell what is a local signal and what is just a strong distant one. Also, someone in the next town might be impossible to receive directly but are still getting thousands of miles. In the last 24 hours, there were reception reports for 7 stations transmitting HF PSK from the IO84 square (mostly Cumbria and Lancaster). These were:
2E0ZYF
G0LWU
G6LSO
G6WLP
M0MOL
M0ZIF
M6DXD

Thursday, 27 January 2011

Antennas 2001


Antennas when I was in Dalton, looks like about April 2001. Watson W300 dual bander on a 12ft pole. Dipole for 50 MHz on the side of the pole. I had a 50 MHz dipole up for a few years but never once had that band while it was up. I usually just had it plugged into a scanner.
In the background there is the Solarcon A99 which was also on a 12ft pole round the back of the house.
The W300 was fed with Mini-8 coax at the time, and everything else had RG-58.
Scanned in from an analogue photo. Found the photo this week while going through some old boxes of computer bits.

Sunday, 2 January 2011

1st Chaser QSO of 2011

My first SOTA chaser QSO of 2011 was with 2E0OCC/P on G/LD-050 Gummers Howe, on 145 MHz FM.