-
You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
JO GUNN 8 + 8 "Killer" STAR
- Thread starter Robalo
- Start date
Nice job Robolo! I am impressed with your work and your willingness to actually "DO" some antenna work and experimenting!
The tower is missing 3 sections to get it to 100' unless it is some very unusual design that uses 3 real long tower sections. Also, the tower is using straight bracing which means it should be guyed. Just because you can crank them up doesn't mean they don't need to be guyed!
According to the math formula that recently came to light on these forums, that antenna should have 32db of gain (12 + 4 + 4 + 4 + 4 + 4)!!! Go get 'em! 8)
The tower is missing 3 sections to get it to 100' unless it is some very unusual design that uses 3 real long tower sections. Also, the tower is using straight bracing which means it should be guyed. Just because you can crank them up doesn't mean they don't need to be guyed!
According to the math formula that recently came to light on these forums, that antenna should have 32db of gain (12 + 4 + 4 + 4 + 4 + 4)!!! Go get 'em! 8)
Robalo said:
Let's review Robalo's picture here a minute......
First of all, you NEVER climb a crank-up tower when it is extended......BUT......this antenna system appears to be guyed (as suggested earlier in this thread by me) and he has positively LOCKED (mechanical lock) the sections using a wood block. Good job and that's the safe way to do it!
I also want to point out the the ground plane radials are NOT in line with the beam radials. Another good job and a huge mistake people make when stacking a ground plane over a beam. Had those elements been in line, they COULD have affected the radiation pattern of the beam! The ground plane doesn't care. There may still be some interaction, but it has been minimized. A longer mast would help by increasing the spacing between the two antennas. Using a iMAX 2000 (no ground radials) is also a good option.
All in all, a good job executed by Robalo and his friend! Robalo is the MAN!
^^ i dont think using a imax over a beam is a good idea. becuase there is a ground plane. the coax.
thanks for taking the time to review my pictures, im learning with each critique i get, we were experimenting with the p-500 on top of the jogun but it didn't work. it didnt affect the SWR on the Jogun at all but it did on the p-500. the weird thing is that the p-500 doesn't have interference but it doesnt reach far and the Jogun works well but it has alot of interference so we have to try with a different antenna for local
any other suggestions welcome
any other suggestions welcome
Just curious, if you have a motor drive on that sucker...why climb it at all extended?
Also, that beam has some really decent gain, the 'interference' could be due to the gain. Maybe try a radio with a decent attenuator and RF gain and spin it back a bit?
Also, have you tried hunting the source of the noise to make sure it isn't on the premises somewhere...like a sodium light or something else with a noisy power supply? Grab an AM radio and walk around with it or try shutting down the service panel so that only the radio power circuit is on. Then, as you turn each breaker back on, see what turned on to cause the noise.
Sometimes noise just means you can hear well. Particularly with the lousy band conditions these days.
Also you didn't mention the radio, the power supply and the station ground configuration.
Also, that beam has some really decent gain, the 'interference' could be due to the gain. Maybe try a radio with a decent attenuator and RF gain and spin it back a bit?
Also, have you tried hunting the source of the noise to make sure it isn't on the premises somewhere...like a sodium light or something else with a noisy power supply? Grab an AM radio and walk around with it or try shutting down the service panel so that only the radio power circuit is on. Then, as you turn each breaker back on, see what turned on to cause the noise.
Sometimes noise just means you can hear well. Particularly with the lousy band conditions these days.
Also you didn't mention the radio, the power supply and the station ground configuration.