RF Choke with MTFT Broadband Balun
Transceiver: YAESU FT-817, max. 5W
Antenna: WiMo MTFT with 40m Longwire, 12m above ground
I fed the antenna via a Ten Tec ATU, about 10m RG58 coax, ending in a RF-choke and a MTFT Broadband Balun. The balun was connected to the huge metal construction supporting the water tanks, wich is connected to the mains ground and the armement of the concrete roof (water pipes are all plastic).
Despite the small distance between RF choke and balun to the TV antenna, I produced no TVI at all.
I could work 10m, 15m and 20m with much the same settings at the ATU, 40m and 80m needed considerable adjustments.
According to the suggestions of DL7AB I plan to insert a coil near the feedpoint, in order to get a better resonance on all bands. I hope either to get rid of the ATU at all or to have less to adjust for 40m and 80m.
For my adjustments I use an AEA VIA-HF Analizer .
Have a look at the Log:
Date Time Call Freq. Mode Prefix RST-Out RST-In Zone 10/01/02 1403 C98DC 21.298 SSB C9 59 57 37 10/04/02 0735 DL9HO 14.270 SSB DL 59 44 14 10/04/02 0735 UA3A11 14.270 SSB UA SWL 57 29 10/04/02 1413 IZ7DOK 21.251 SSB I 59+ 59+ 15 10/07/02 1028 HB9AAL 14.317 SSB HB 59 44 14 10/07/02 1917 PY3NZ 21.280 SSB PY 59+ 59 11 10/08/02 1522 DL1AAH 21.270 SSB DL 59+20 59 14 10/09/02 1532 LX2CL 21.265 SSB LX 59+ 55 14 10/10/02 1322 9K2ZZ 28.500 SSB 9K 59+ 59 21 10/10/02 1344 DJ1ZV 28.460 SSB DL 59+ 57 14 10/10/02 1520 9A2TD 21.247 SSB 9A 59 57 15 10/10/02 1547 G0JFM 21.246 SSB G 59 54 14 10/12/02 0459 SV3EXU 14.244 SSB SV 59 59 20 10/12/02 0534 EA5KB 14.260 SSB EA 59 58 14 10/12/02 1435 EY7AD 21.288 SSB EY 59+20 58 17 10/12/02 1454 SP5KP 21.242 SSB SP 59+10 58 15 10/12/02 1517 SM7CRX 14.281 SSB SM 58 56 14 10/13/02 0655 HB9CCL 14.248 SSB HB 59 56 14
I am aware of the privilege to work with the prefix 5B4, the "native" Cypriot OMs consider the bands to be dead, if their first CQ call is not answered and switch off..
