Another country on the 70-MHz band

[i0jx]

Italy is the 34th DXCC entity ( 28 Europe, 2 Asia, 3 Africa, 1 North America, see http://www.70mhz.org ) now having an ham-radio allocation in the 70-MHz range (4-meter band). On July 12th the Italian Authorities released three 25-kHz segments centered around 70,100, 70,200 and 70,300 MHz respectively. The story began with the request of a few hams to carry out an experimental campaign under the technical coordination of a University, and concluded with a general authorization for all Italian amateurs ( see http://www.space.it/70mhz/ with an English summary at the bottom of the page ). Although the authorization expires on December 31st 2007, the perspectives of a permanent allocation to Italian amateurs appear good. The band offers opportunities of transatlantic contacts during the summer sporadic-E period ( you may listen the recording of the EI2IP signal as received by VE9AA on http://www.youtube.com/watch?v=bvob5IxAvc8 ), and intercontinental contacts via transequatorial propagation ( and F2 too? ) during high sunspot periods.
Tony I0JX

[N2RJ]

Which country in NA has a 4m allocation?

[n1ese]

Quote[/b] (N2RJ @ July 24 2007,14:11)]Which country in NA has a 4m allocation?
Greenland

- JT

[n3jbh]

Greenland is in North America? http://www.qrz.com/iB_html/non-cgi/emoticons/wow.gif

[N2RJ]

Yes, Greenland is an island associated with NA.

[n1ese]

Geography 101

http://go.hrw.com/atlas/norm_map/namerica.gif

[wa4gch]

Quote[/b] (n1ese @ July 24 2007,17:14)]Geography 101

http://go.hrw.com/atlas/norm_map/namerica.gif
VERY INTERESTING ......

Hey now THERE is a spot for wide band digital

[KI4MRU]

I tried to go to 70mhz.org and it says my IP address is banned. http://www.qrz.com/iB_html/non-cgi/emoticons/rock.gif

[N7PLC]

Doing my best Johnny Carson...."I didn't know that"

[K2PG]

In this country, 70 MHz is in the middle of TV channel 4 (66-72 MHz; visual carrier at 67.25, aural at 71.75). A lot of TV broadcast stations will vacate channels 2 thorough 6 when the FCC orders analog television off the air on February 17, 2009. Only a handful of stations will remain on those channels, as they are unsuitable for digital television. Most digital TV will broadcast on the high VHF channels (7 through 13, 174-216 MHz) or on UHF channels 14 through 51.

There will only be a few television stations left on channel 4 after February 17, 2009. That might be a good time to petition for an amateur allocation on a secondary basis in this country, with the band being unavailable within about 200 km of a channel 4 TV station. Channel 4 areas will be North Pole, Alaska; Rock Island, Illinois; Manteo, North Carolina; Crandon, Wisconsin; and Oak Hill, West Virginia.

The least-used VHF channel after the analog shut-off date will be channel 6 (82-88 MHz). That would be suitable for expanding the FM broadcast band.

[i0jx]

In Italy we also still use channel B in a few areas. As a matter of fact my 70-MHz antenna is a modified 4-element TV antenna originally resonating at 67.5 MHz. I am not sure how they will manage the interference cases. Anyway the number of active stations is here still quite low, mainly due to lack of advance notice and equipment operating on 70 MHz, The only suitable radio is the Yaesu FT-847 which however suffers from high receive noise factor and poor transmit efficiency (modifications have already been published). Until now I made about 120 QSOs, the very large majority of which with UK stations (G, GM, GW, ...) via sporadic-E propagation. I hope the US hams will get the band sometimes in the future! 73 Tony I0JX

[k4eez]

hi all
just thougt this might pose some intrest to the 70mhz band...

The History of the Four Metre Band

by Jack Hum G5UM

Historically, the British radio amateur had held an allocation in what before the war was known as 'the ultra high frequencies' meaning 56 M/C (yes megacycles in those days!). After the war when amateur transmission was resumed the British amateur was allocated 58.5 to 60MHz, but this was available to him for little more than three years, with the spectre of BBC Television looming on the horizon and requiring this band (the first TV station was on 45 M/C's but the second one, at Sutton Coldfield, was scheduled to go plonk of the middle of the five metre band. There was a commemorative 'Last Night on Five' on March 31st, 1949, when the small number of pioneers who used the band foregathered to see the curtain drop).

Very soon the National Society began to lobby for an allocation above the Band One television spectrum and made a point that there existed a long history of 'Ultra High Frequency' operation so couldn't something be found to replace 'Five'? Indeed it was, and it was called 'Four', initially a small chunk from 70.2 to 70.4MHz, but steadily widened as the years passed and as the national society made a case for more room at 4 Metres, and also asked for easement of the restriction on 'no operation within 50 miles of the Jodrell Bank Radio Telescope'.

The truncated 70MHz band became available to UK amateurs in November, 1956. The 200KHz then available amply accommodated the few who tried their hand at the new band, and today when it extends from 70.025 to 70.5MHz, there is more than enough room.

However, in the earlier days there wasn't, for much of the band was taken up with wide-band amplitude modulated phone transmissions (FM was years away). It was soon found that AM didn't travel far, and the CW ethic was always a strong feature of 'Four', enabling stations with modest power allowed to enjoy almost nation-wide range.

Part of the folklore of 'Four' was that the British were given it in order to provide some QRM to the military, who also shared it. Sometimes during Summer exercises by the military peculiar noises from them may be heard, but the radio amateur virtually enjoys QRM free use of the band for virtually all of the year, apart from Sporadic-E and Tropo manifestations from foreign broadcast stations which share the band.

The 'lifts' which became evident early on in the history of 'Four' raised hopes that overseas administrations would see fit to give the band to their nationals but none did. There was a modest amount of activity from British sovereign bases such as Cyprus and Gibraltar (there still is) but for most of the time the 70MHz band was 'peculiar to the British'.

Activity from sovereign bases has been fostered by Service personnel posted to them and inspired by an enthusiasm to try this unusual band. The results achieved under anomalous 'lift' conditions made many wish that other overseas countries could be permitted to use it. Although they weren't, it should be reported that several enterprising Continental operators equipped themselves with 4 metre converters and were able to enjoy cross band contacts with the British.

It is worth emphasising that because 'Four' is 'peculiar to the British' and is not a world wide allocation, the Japanese don't provide any of their 'world-wide' mass produced rigs for it. Result: much of the equipment used on 'Four' is home built. Transverters are also becoming increasingly popular as a means to get going on the band from an existing HF or 144MHz Transceiver.


Antennas are 'big bedstead like' compared with the more compact units used on 2m and 70cm. Several excellent commercial designs are available.


Meteor Scatter is sometimes easier on 'Four' than on 'Two' because reflections from meteor showers appear to last longer.

RSGB awards have been available for 70MHz since 1961. The first Four Metres and Down certificate for 70MHz was awarded to G3EHY in 1953. The first GM to win it was GM2UU in 1967. Requirement is 3 countries and 30 counties. The Senior award requires six countries (just obtainable within the British Isles) and 60 counties. Senior number One was won by G3SKR in 1966. The first GM operated station to win it was GM3KSU/P in 1972.

Firsts between GM and G on 'Four' are lost in the mists of antiquity. Sundry requests in the ham radio media for people to come forward to claim say 'first' between GM and G or whatever have been greeted either by stony silence or undue modesty.

Artical by
Jack Hum

G5UM

[WA3RA]

I did quite a bit of crossband (4 to 6 and 4 to 10) a few years back, and always found it to be an interesting band. I never did have much trouble with channel 4, because of the narrow bandwidth of the ham signals, and corresponding narrow receiver bandwidth. There was still a surprising amount of Es there, which made for some interesting effects when coupled with scatter!

[m0pme]

Its a nice band there are only simplex contacts and a great bunch of hams who will help you get on the band. I hope you will get a part of the band when your tv stations goes to higher bands. 73 DE Barry

[KD7YUF]

I think that the VHF low band is better for HDTV than UHF and possibly the VHF high band. One thing that proves this is that on another forum I read there was a huge thread on HDTV one person who lives 65 miles away from a city with UHF HDTV stations and a VHF low band one on ch 4 says that they cannot get the UHF stations despite the fact that they are 1 megawatt! and this is with a good long range VHF/UHF antenna which provides good analog reception this person only managed to get one HDTV station which is the VHF low band one on ch 4 and they are using about 60KW! The problem with the UHF band is that because of the short wave lengths transmissions are greatly affected by foliage such as trees and also terrain has a greater effect on UHF than on VHF.