The setup that I have at the moment isn't the setup that I'd be trying eme with, but only the antenna's and last run of cable will change. Currently for 2m and 70cm I have a pair of 'cheap yagi's' in vertical pol for sat work. The 2m yagi is 4el and the 70cm is 8el - I hope that the noise floor will reduce when I get the 7el lfa yagi up for 2m. The 70cm will change to a homebrew 15el yagi.
My full setup is:
TS-2000 for the radio - Cables for 2m and 70cm are separate cables, but identical - 30cm RG213 patch cable to a bias tee (to feed power up the coax) then a 10m run of LDF450 to switching relays (switch between a vertical antenna for repeaters and the yagi's for sat work), then 4m run of RG213 to the 2m and 70cm cheap yagis. When I get the 2m lfa and homebrew 70cm yagis in the air then the 4m run of RG213 will be changed to SCF12-50J cellflex to reduce cable loss.
Pre amps are boom mounted ARR units, MSP144VDG-160 for 2m (0.55dB NF and 24dB gain) and MSP432VDG-160 for 70cm (0.55 dB NF and 16dB gain).
With the TS-2000 pre amp on and the ARR pre amp on the noise floor is (just checked) S4 pointing west (S2 when pointing up 45 degrees), but when I swing the yagi around to the SE it climbs to S10+ (S7 pointing up at 45 degrees) !! I have a feeling the 'cheap yagi' is half to blame and (fingers crossed) the noise floor will reduce when I get the lfa up. Without the ARR pre amp on the noise floor drops to ZERO on 2m !! 70cm is all fine with the noise floor at zero or maybe S1-2 at the highest.
I haven't had a good play with the DSP on teh TS-2000 yet, do you narrow the filters right down? What cut off's do you usually run at for the filters?
Loooong term I might look at 2 x lfa's for 2m and 2x lfa's for 70cm. but that's loooong term.
Cheers
VK3DXE wrote:
Is that S6 in all directions? What antenna design are you currently using?
On moonrise I have up to S9 at the horizon, but that drops off rapidly above 30deg above the horizon. I think that's part of the reason there are so many Europeans on the moon, but none of the regulars are running dated yagi designs.
How much gain do you have from your preamp? Have you tried a different one? Could be simple front end overload. What's your noise floor without the preamp? Do you have DSP? Without the DSP in the IC-7000 I probably wouldn't hear much here either.