G/M: SINCE BEAM GAIN VARIES SO WIDELY REL TO FREQ, AS SEEN FROM
RECENTLY POSTED TABLES HERE, I STARTED PONDERING VARIATION OF GAIN ON
TRANSMIT VS. RECEIVE.
IN HIS BOOK "HF ANTS FOR ALL LOCS", MOXON STATES ".....INCREASING
THE NUMBER OF ELEMENTS FROM TWO, TO THREE OR FOUR WITH CLOSE SPACING HAS
COMPARATIVELY LITTLE EFFECT ON TRANSMITTING GAIN." AND ".....IN TERMS
OF TRANSMITTING GAIN, THE LARGER (3&4 ELE) BEAM IS SLIGHTLY DOWN EVEN
COMPARED WITH THE BEST THAT CAN BE ACHIEVED WITH TWO ELEMENTS,......".
FINALLY ".....FOUR-ELEMENT DESIGN IS QUITE POOR IN THIS RESPECT(XMIT
GAIN) SO THAT THERE SEEMS TO BE HERE A PARTICULARLY STRONG CASE FOR THE
USE OF SEPARATE TUNING UNITS FOR TRANSMISSION AND RECEPTION."
WOW, IF THIS IS TRUE, I WUD SURE LIKE TO SEE TRANSMIT GAIN FIGURES
FOR SOME OF THE MORE POPULAR BEAMS!
IF ANY PARASITIC GAIN EXPERTS CAN SHED MORE LIGHT ON THE ABOVE
STATEMENTS, I AM HUNGRY TO HEAR IT, HAVING RISKED MY LIFE AND WALLET TO
GET TO TOWER/BEAM COMBO I PRESENTLY HAVE.
WILL DEFINITELY ATTEND THE "ANTENNA TECHNOLOGY" FORUM AT DAYTON. WE
ALL NEED A BIG BREAKTHRU IN DIRECTIONAL GAIN, BOTH XMIT AND RCV.
73/DX, DOUG - NX4D
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