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

Puxing PX-2R

I recently ordered a Puxing PX-2R handheld and it arrived today.
This covers 400 - 470 MHz, with 2 watts RF power.
The battery is a 3.7v mobile phone type and charging is through a Nokia type 2mm power connector at 5 volts, so it will charge from a USB port (cable supplied) or Nokia phone charger.
It has a female SMA antenna connector (unlike other Chinese handhelds).
The manual has no information about how to store frequencies into the 128 memories or connect to a PC for programming, but there is programming software available on the Puxing website and the 2.5mm speaker/mic socket must be used for the PC connection. There is no mention of 6.25KHz steps either, the menu allows only 12.5 or 25 KHz channel steps, but if you type in a 6.25 KHz offset frequency (e.g. 446006) then it tunes in 12.5 KHz steps from that frequency (446.00625, 446.01875 etc.)
As usual for this type of radio, the S-meter is useless, taking about 2 seconds to respond to any change in signal and showing either full or nothing.
For £28 including postage this is worth the money though.
Forum discussion on this handheld
Instructions on storing memories

Nokia NetMonitor

I've got an old Nokia 3310 phone which I've had for nearly 8 years. I don't use it as my main mobile any more (not since December 2004), but after I got a new phone I unlocked it and enabled the Network Monitor functions. The unlocking was through a serial port cable which goes to a special connector underneath the battery.

The Network Monitor screens show lots of data about the phone's battery, software and radio transceiver. The best ones are tests 3,4,5,11 and 17. The current channel number and Cell ID are shown, as well as the channel and signal strength of nearby cells. Signal strengths are in dBm, how can a cheap mobile phone display signal strengths in 1dB steps but on the amateur bands we still have to have meters in S-units which may or may not be about 6dB per unit except when we're using FM?

Other phones often have some kind of Network Monitor screen (there's an Android app which can show the Cell ID but not the channel number, at least on my HTC Hero). On my Sony Ericcson K750 I could get Cell ID and channel numbers on a built in test screen.

The most interesting test of all is number 17, BTS Test. This locks the phone to a single radio channel, so it can't look for the nearest base station. The channel number is selected by storing it as a phone number at address book position 33 on the SIM card.
You can go up a hill and get a base station far away (over 50km), as long as there is nothing local on that channel. At home in an upstairs room I can get the Vodafone base station at Lancaster (the same site as the GB3LD repeater), which is on channel 77 (950.4 MHz).

The base stations are identified by the country code, network number, LAC and CID. LAC is the region of the country where the station is. This helps give a rough idea of where an unknown base station might be if there are none nearby.
For Vodafone, the LAC in this local area is 170.
The CID is the Cell ID. It could be used more than once in the UK, but with a different LAC. Different networks have different CID numbering systems. O2 has the most meaningful.
For O2, the CID is usually a 5 digit number.
The first digit is the sector (the direction of the base station antenna, where there are usually 3 different antennas on separate frequencies, spaced at 120 degrees round the mast). The sector number is 1, 2 or 3.
If the CID is less than 5 digits for an O2 site, an omnidirectional antenna is being used or only a single panel. This might be because it's an old site which has been around from the analogue days or it only has to cover a small area like inside a tunnel.
Sector numbers usually go clockwise starting with 1 as the most northerly pointing antenna. So a CID of 15432 would be base station 5432, beaming north. 30439 would be base station 439, probably beaming towards the south-west. If this was simply CID 439, it would probably be an old site with a single omnidirectional antenna.
If the last 4 digits are 0001 to 01499 then there's a good chance the site had been used for the analogue cellular system, but not always, some newer sites use numbers in that range.

Some older Vodafone cells use a similar numbering system but with the sector number at the end. If the last digit is zero then it is omnidirectional. Newer sites don't follow this system and the numbers mean nothing.
Example:
The Lancaster Langthwaite site I get at home has a CID of 1643. This is an old site, which was in use for analogue phones. On the Sitefinder website, this is shows as being site number 164. I'm roughly west of Lancaster, so sector number 3 will be mostly directed towards Barrow.
At the railway station in Barrow there is a Vodafone site with 2 omnidirectional antennas. This is site 3753 on Sitefinder and the CID is 37530.

Channel numbers on the 900 MHz band (O2, Vodafone) are 0.2 MHz offsets from 935 MHz. So channel 75 is 950 MHz.
O2 normally use 37 - 59 and 101 - 124.
Vodafone normally use 65 - 99
On the UK networks, only the odd channel numbers are widely used, except for channels 123 and 124 (for some reason channel 123 is missed out and 124 used instead).

At 1800 MHz, T-Mobile are using the channel 575 - 715 range and Orange in the 750 - 870 range, but that might change now it's the same company.

Some local sites:
O2
Morecambe Bay
CID 10439, channel 109 (North)
CID 20439, channel 101 (towards Ulverston)
CID 30439, channel 57 (towards Barrow)

Lancaster TV mast
CID 10210, channel 53
CID 20210, channel 55
CID 30210, channel 124

Vodafone
Morecambe Bay
CID 2930, channel 91
omnidirectional

Langthwaite
CID 1643, channel 77
2 other sectors unknown channel numbers

Dalton TV mast
CID 8334, channel 65 (Dalton town centre)
CID 8335, channel 93 (south-west)
CID 8336, channel 97 (north)

All except Dalton TV mast used to be analogue sites.
Old analogue control data channels:
Morecambe Bay Vodafone = 935.8375 (omni)
Morecambe Bay Cellnet = 943.5125 (omni)
Langthwaite Vodafone = 935.6875 (sector 1), 935.8625 (sector 2), 936.0375 (sector 3)
Lancaster TV mast Vodafone = 935.7375 (omni)
Lancaster TV mast Cellnet = 943.0875 (omni)

Nagoya UT-108

Don't buy a Nagoya UT-108 dual band mini magmount antenna. They're available on Ebay from a few places. There are a few other in their range of mini magmount antennas, which are smaller or have different connectors.
On my car roof, it was a lot worse on 70cms than the proper mobile antenna (Watson W-770 copy) which was mounted quite close to the ground on the tailgate. Probably the RG-174 coax being so lossy but it didn't seem to be resonant on any amateur band at all. Even when the car body was in the way, the W-770 was much better.
The mini magmount was OK around 165 MHz, compared to other antennas, but none of the others were meant to work on that frequency anyway.
Other mini magmount antennas are probably the same, but the last one I had (I think it was from Moonraker) fell apart soon after I bought it. Other stuff from Nagoya looks like it's a direct copy of the Diamond/Watson antennas.

Multi Ranger 200

Watson Multi Ranger 200 on the car. I've not tried this at over 30mph but probably won't be driving very far with a HF mobile antenna on.

RG8-Mini

RG8-Mini (or RG-8X) is the 50 ohm coax size which is somewhere between RG58 and RG213, 7mm diameter. You might use it where you need flexible coax but where RG58 isn't good enough. But is it really any better than RG58?
It seems to be sold more as a high power HF cable than for use where low loss matters, and I first saw it being used on CB. There were red and grey versions of this cable.
A few years ago I made up a cable of black RG8-Mini, about 11 metres long with PL259 plugs on and sometimes used it for portable operation. I thought it would probably be better than RG58 so wasn't too worried about the loss. But this week when I was on Muncaster Fell I had a listen around 433 MHz and didn't hear very much. I could hear more on my handheld's own antenna than on the 2m/70cm mobile whip that I had set up on a pole.
When I got home I measured the loss of this 11m of RG8-Mini on 2m and 70cm. With a very short piece of RG58 I was measuring 9 watts on 70cm. Replacing that with my coax cable reduced that to 2 watts! That's about 6.5dB loss or 0.6dB per metre. RG58 is supposed to be better than that on 70cm. At 144 MHz, the loss was about 2dB which is more like RG58 should be.
The official figures for RG-8X are better than this but it doesn't seem as much of a standard as RG58 or RG213. I think I bought mine at a rally and I had some on a 2m/70cm dual bander at home before I put decent coax on it so that might have been the same piece of cable.

70 MHz WSPR

There's some activity on 70 MHz WSPR now, on 70.0286 MHz. I can receive G0MJI from Liverpool, using my Icom IC-7000 and the dual band 2m/70cm colinear on my chimney. On the proper 70 MHz dipole in the loft, there is no improvement in S/N because there is more noise indoors. I've nothing to transmit on 70 MHz SSB though.
Alex G7RNX in Dalton was also on 70 MHz WSPR on Sunday and could be received by G0MJI and G3ZOD (Stockport).

Made a PC to radio interface for an FT-847 before finding out it wouldn't work properly because...
On the Yaesu FT-847 there are separate connectors on the back for FM and SSB data modes. The 6-pin mini DIN socket can only be used to transmit on FM (there seems to be receive audio on SSB through it though). On SSB, transmit and receive audio are through a 3-pole minijack socket. The tip of this jack is for transmit audio and PTT (ground through a resistor to transmit).
The 6-pin socket can be used for the PTT on both FM and SSB.
Connecting a cable directly between the headphone socket on a PC and the FT-847's SSB data socket made the radio stay on transmit. There needs to be a capacitor to block any DC current path which might key it up.
It seems a bit of a strange thing to have 2 data sockets but when the FT-847 was designed, people weren't using a PC sound card for data modes so would have had a standalone packet TNC.