Saturday, March 3, 2012


Bodo DL3OCH will be in Abuja as 5N7Q between March 7-14, 2012 for maintenance (work) of the broadcasting station based there.
Operating using one of the largest fully rotatable short wave antennas in the world. The antenna gain is over 20dBi on all bands from 10m-40m.

5N7Q QSL via DF8DX.

About largest fully rotatable short wave antennas in the world:

ALLISS is a fully rotatable antenna system for high power shortwave radio broadcasting in the 6 MHz to 26 MHz range. An ALLISS module is a self contained shortwave relay station that is used for international broadcasting.

Feed-line Construction:

Mechanical construction & Specifications:

Antennas type for high frequencies:
Three HRS array antennas types are available for broadcasting in the traditionalshortwave broadcasting bands.
For tropical and lower frequency shortwave broadcasting
HR 4/2/1 (using low band antenna)
HR 2/4/1 (using low band antenna)
HR 2/2/1

For traditional shortwave broadcasting
HR 4/2/1
HR 4/4/1

For highly directional shortwave broadcasting
HR 6/4/1
HR 6/2/1

Build-up ALLISS module antenna video (French language)

Same video from New Zealand (English language)

ALLISS allows a broadcaster to change the following shortwave transmission parameters:
direction (azimuths from 0 to 360 degrees, rate: ~1 deg / 6 sec)
broadcast frequency
antenna configuration (ie: HR 4/4/1 -> HR 6/4/1)

Typically ALLISS modules possess a 500 kW polyphase shortwave transmitter.

List of Broadcasters who’s using ALLISS modules
RFI, Radio France International
Radio France International

Additional info:

For example. the International broadcasting center of TDF (Télédiffusion de France) is at Issoudun/Ste Aoustrille. Issoudun is currently utilized by TDF forshortwave transmissions. The site uses 12 rotary ALLISS antennas fed by 12 transmitters of 500 kW each to transmit shortwave broadcasts by Radio France International (RFI), along with other broadcast services.

Price of one ALLISS module antenna is $10.000.000 USD

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