8589357289

Propagation Predictions

The months of June, July and August are the most unfavourable for dx conditions, especially on 28MHz.

On 28MHz even Africa and South America will not be heard with certalnty, perhaps mainly on days with above average F2 MUFs. Contacta with Norlh America and Japan will be impossible.

On 21MHz the unfavourable conditions will also be noticeable. Norlh America, Australia and Japan will only be heard on days with above average F2 MUFs. Contacts with the west coast of Norlh America will be poseible In the early hours of the mornlng, and with Japan and Australia In the latter part of the evening via the Indlrect path. Stations In Southern Europo will find betler conditions than lhose further north. Somo compensation for the poor dx conditions will be provided by $poradic-E short-skip conditions during the summer months for distances of about 500 to 2,000km. These short-skip contacts will be possiblo bocause of the exlstence of a Spor-adic-E layer at frequent intervals.

14MHz will offer excellent night-tłme dx conditions during the summer months. Thls band will be opon for trafne to North and South America during the tatter half of the night. The most favour-able conditions for trafflc to South Africa will be between 1900 and 2300gmL As it is now wlnter In the Southern hemisphere, atmos-pheric dlsturbances will be relatively Iow and trafflc sbould be good during the night.

On 7 and 3.5MHz the chances of dx during the night włtl be rela-tively Iow, as the nlghts are short and atmospheric dlsturbances will be strong.

The dead ione will not appear on 3.5MHz. even shortly before sunrise.

The provisional sunspot number for Aprll was 70*7 with the highest period of solar actlyity occurring in the middle of the month. The predicted smoothed sunspot numbers from the Swlss Federal Observatory for August. September and October are 61.59 and 57 respectively.

14MHZ    JUNE 1971

USA-East (W1-4)

USA-West (W6 7)

(6Y5/FM/TI BrazM Cpy)

South Africa (ZS)

SE Asia (HS.9M2J

Australia (VK)

Ja (JA)

21MHZ    JUNE 1971

USA-East (W1.4)

USA-West (W6 7)

6Y5/FM/T Brazil (PY)

South Africa (ZS)

SE Asia (HS.9M2)

MOBILE RALLY NEWS

Elvaston Castle Mobile Rally, 13 June

This will take place at Elvaston Castle County Park flve mlles south-east of Oerby on the B5010. Ali the usual attractions. Talk-in stations: G3EEO on 160m, G3ZBI on 2m. DF run In the afternoon— bring o/s sheet 121. Spedal car park. Facillties for caravans— book with Mrs Webb, Elvaston Caravan Park, Borrowash Road, Eivaston, Derby, tel Derby 73735. Further detalls from G3WFU.

Hanworth Mobile Rally, 27 June

Echelford ARS is organizing this event at Hanworth Air Park. approx three mlles south of London Airport along the A305 from London. Talk-in stations from 9am, callslgn GB3HCW, on 160. 80 and 2m. There will be a gymkhana, rabbit show. flower show, licensed bar and refreshments. Further info from A, G. Wheoler. 32 Fettham Hill Road, Ashford, Mlddx.

South Shieids Mobile Rally, 4 July

Taking place this yoar at Redwell County Secondary School, Prłnce Edward Road. South Shlelds. the rally site can be reached elther from Seaburn, along the A183 coast road, turning left at Mareden roundabout onto the 81300, or from the A1(M) vla the A158(M) then onto the A1055 and B1300. The school is half a mile from the coast on the right. Talk-in stations on 160m and 2m, trade stands, raffles, competitions, refreshments. Further info from F. Harrison, G3SFL 42 Woodlands Road, Sunderland. SR67UD.

Cornish RAC Mobile Rally, 4 July

Truro Rugby Club's ground will be the venue for this rally, and talk-in stations will operate on 160, 4 and 2m from 0900gmt. There will be refreshments and a licensed bar. Fuli detalls and a map are obtainable from G3UCQ QTHR.

Upton Mobile Rally, 11 July

Taking place at Hill County Secondary School. Upton-on-Severn, this rally will be arranged by Worcester and District ARC. It will open at 11am and there wiil be a talk-in statlon on 160.4 and 2m. Attractions Incłudod crystal exchange, trade stands, Raynet. fre-quency measuring senrice. and a youngsters* playground and refreshments at reasonable prlces. Further detalls from G3WUI. OTHR. Tel Malvern 3088.

Mobll«er’s Family Outing. 17 July

This event, arranged by the Winchester ARC in conjunctlon with the Montgomery of Alameln School fete, opens at 2pm and will have talk-in stations on 2m and top band. DetaUs from Winchester ARC. c/o Flowerdown House. Harestock Road. Winchester.

Scarborough ARS Mobile Rally, 18 July Taking place at Burnłston Barracks. Scarborough, attractions at this rally will include trade stands, bring and buy siali and raffles. Refreshments will be availabie and there is ample parking apace. Talk-in stations will bo on the air from lOam, G4BP/A on 1,980kHz and G3NRS on 1458MHz.

Australia (VK) Japan (JA)

28 MHz    JUNE 1971

tt»an{6Y5/FMrri>

Brazil (PY)

South Africa (ZS)

SE ASia (HS.9M2)

Australie (VK)

Time (GMT) 00 02 04 06 08 10 12 14 16 1B 20 22 24

S_

Short path 1__

Long path

1-5 days Openings on morę than 20 days

6 -20 days in the month

Vlsitors to Drayton Manor Park Rally on 18 Aprll induded (I to r) G6LD, G2CW (President, RSGB) and G3BA (past-

president. MARS)

409

RADIO COMMUNICATION June 1971