Server maintainence

Saturday 20th September 2014 will see the site down for a few hours while our server is relocated. I would advise that even if you can get on the site Saturday, do not make any posts. Hopefully this change to a new data centre will improve things behind the scenes. I will post a update once the relocation and testing is complete.

All work, text and images © GB7MB

Digital diversity !


Motorola Astro Spectra
Motorola Astro Spectra

Here ’round the Bay area, we don’t just stick with DMR/ MotoTrbo, In fact we’re interested in all commercial digital voice modes. If you’re into getting your ‘hands dirty’ and hacking on old Motorola digital gear for fun, here’s a glimpse of what we play with on dark sunday evenings. It used to be that most PMR conversions were hours of painstaking research, winding coils, doing mathematics, and  actually burning your fingertips with a soldering iron, but now its in mainly  about swapping that soldering iron for a keyboard, so onward with the learning process, and remembering the ‘experimentation in wireless telegraphy’ bit, (remember that ?) and do it just for the hell of it.

Its an Astro Spectra above, one of many different sorts we’ve collected over the last couple of years, nice old sets, 1990s vintage, heavy as a paving stone, no light alloys and thin parts, it really is a solid lump of metal with a radio inside, don’t drop it on your toe. there are portables, more recent versions, but these are just right for hacking on.

The more geekier of you out there may be thinking ‘ oh, p25 ‘ well, its not.

its pure ASTRO – Its what Motorola made before p25 was the standard, its got alot in common, and most Astro Spectra’s ARE p25 – but these are an earlier iteration, and the codec is actually VSELP as opposed to IMBE/p25 sets which most are. We use Astro digital, Astro 25 digital (Motorola’s name for P25) and DMR. for now.

Plenty of these sets are all over Ebay, i got a headless one for a penny,  but they go for about 30 ukp and up.

when buying a Astro Spectra there are several things to think about.

1:) there is a Analogue version just called ‘Motorola Spectra’  avoid unless you want a FM only set.

2:) there are VHF, UHF and 800/900mhz versions and can all have different & software-upgradable features.
3:) the sets are ‘banded’ so a 450-482mhz set needs more work to convert than a 403-440mhz set.
4:) there are 15w-25w  25-40w  and 110w versions, dual head and portable versions (Astro Saber)
5:) there are different front panel versions and they have plenty of channels too.

6:) they are FM and digital, they scan,  have high/low power, are a solid TX, a good sensitive RX.
7:) plenty of well documented information and the community has done much research already
8:) it stops you getting bored with Amateur radio.

9:) professional quality radio and codec, making other ham stuff look like cheap plastic Argos PMR 446 toys.
10:) will make you more attractive to the opposite sex
11:) become an 1337 experimenter again !

 All work, text and images © GB7MB

Get your DMR-MARC ID

If you want to use Amateur DMR-MARC repeaters, you need a ID number, its free, easy and just identifies you to the network,

so go here, agree you wont use AGC (or we’ll send the boys ’round) or ARS, and its upto you what to type when it asks what is your nearest DMR repeater, you can ‘try’ to put GB7MB, but as the repeater isn’t on-air yet its probably better to put  ‘GB7HM’- in N. Wales, (same site as GB3CR up on Hope Mountain) if you get a query, as the DMR-MARC network wont know us yet.

All work, text and images © GB7MB

Weather station


weather station
weather station

We have now installed a weather station at the GB7MB site. This can be found at until we manage to get the links up on the site.

All work, text and images © GB7MB

Site has been reset

Due to the site being compromised, and there only being a few registered members we have decided to start from scratch. Hopefully this will give us the chance to sort things out. It will take us sometime to get things working and to add the downloads back. I can only apologize for the inconvenience this  has caused our members. I hope that when the time is right you will decide to re-join us. No data was compromised and the intrusion was detected within a few minutes.

We will of course post any updates on the application for GB7MB as we get them.

All work, text and images © GB7MB