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4 m PA design feature
Published on 26 January 2007 by G6GVI

As promised, Geoff GI0GDP has provided full details of his design for a simple solid-state linear amplifier for 70 MHz.

This can be viewed in the Technical Features section, along with a number of other articles on antennas and transmitter equipment.

GB3CFG interruption in service
Published on 15 January 2007 by G6GVI

GB3CFG has been off-air since the start of the year due to problems with the mains supply.

Please do not adjust your sets!

Four Metres Site Ten Years Old!
Published on 22 December 2006 by gm4aff

Yes, incredible but true! The Four Metres Website is 10 years old on the 27 Dec!


Conversion of old multimodes to 4m
Published on 14 December 2006 by admin

The Equipment section of the 4m Forum contains some notes on the conversion of old 2m multimodes such as the FT221, TS700 and FT225 into dedicated 4m transceivers:

FM telephony channels
Published on 13 December 2006 by Nige-G7CNF

The last four years have seen a large influx of new users on 4m FM, but the present bandplan prescribes ten channelised frequencies to 'digital modes' and only five for telephony.
As we move into the new solar cycle, the Es season will bring more activity on 4m FM: will five channels be enough?

A new Topic (with an online poll) has been started in the Digital modes Forum:
Please take a look at the thread and cast your vote.

David G4ASR, the RSGB VHF Manager, will be pleased to receive constructive comments and suggestions on this matter.

The history of the Four Metre Band
Published on 11 December 2006 by Stewart G1HHO
In the January edition of Practical Wireless there is a interesting article by David Butler G4ASR on the history of the 4 metre band.

New feature on FT-847
Published on 14 November 2006 by G6GVI
A new feature article provided by Nige G7CNF has been added to the Technical Articles section:

This includes some detailed measurements on an FT847 operating on 4 m, and suggests a modification to reduce the high-level spurious signals found.

More recent information indicates that the UK "C-2" versions do not suffer from these problems:

LX QRV on Four
Published on 4 July 2006

Jack LX1JX is currently the only station QRV on 4m from Luxembourg, and uses
a TS430S with and OZ-transverter and a small PA. His antenna is a 6-ele yagi (Eagle 4M6DX from Vine Antennas), but this is not yet installed on his 12m tower, but only a few metres above ground on a small pole.

In the first couple of days of July, Jack made a crossband 6m/4m QSO with Belgium, followed by 4m Firsts with Portugal and England. Bo has been updating the Firsts section:
with these new contacts, and you can see more details of these and other operations in the DX News section of the Forum:
Comments (1)

SV's on 4 m now
Published on 16 May 2006 by SV1DH

Since 12-May-2006 all SV HAREC level-A  and CEPT licensees are allowed to transmit on 4 m (70.20-70.25 MHz) using narrowband modes, up to 3 kHz bandwidth (i.e. no FM) for experimental purposes. The maximum output is 100 W PEP.

Active SV1 stations from Athens are: SV1OE, SV1AHX, SV1AHP, SV1DH (on SSB and CW at 25 W and 5-8 ele yagis) and few others soon. There are also some SV2s.

Hope to work you all soon

AKD 4001 back in production soon
Published on 30 April 2006 by M3SGC

According to the GAREX website, Peter Longhurst has stated that the AKD 4001 4 metre FM transceiver will soon be back in production!

Maybe this will encourage some more Foundation licensees onto the band?