Ok, so I've been sitting for the past few minutes crunching some numbers trying to come up with a figure for the ERP of my "10M ham" station now, and how the ERP will change when I re-do most of the coax run in a few weeks. I'm unsure how accurate my math is, so for those who actually KNOW how to do this, please chime in and offer up your corrections/advice.
This is a rundown of my station now, as it sits. Listing each item and the approximate dB loss for each item.
10 coax connectors, -5dB
1 coax switch box, -1dB
1 low pass filter, -1dB
75' RG8X coax, -1.2dB
1 wattmerer, -1dB
Total of 9.2dB loss from the radio to the antenna. At a 9.2 dB loss, a 50W "10 Meter" radio should have an ERP of 17W getting TO the antenna.
The antenna is a Solarcon A99, which reportedly has a gain of 1.8dBi, and I'm calculating roughly a 1.6X increase in power due to the gain. Which should then put the ERP actually being transmitted at 27W.
Now, fast forward to my new setup. In which I'm upgrading coax, and taking out an item or two.
6 coax connectors, -3dB
1 switchbox, -1dB
100' LMR400 coax, -0.64dB
1 wattmeter, -1dB
New total of 5.64 dB loss (A 3.5 dB change over the old setup) from the radio to antenna. At 5.64 dB loss, a 50W "10 meter radio" should have an ERP of 27W getting TO the antenna.
Again, Solarcon A99, 1.8dBi gain would yield an ERP of 43W actually being transmitted. If I upgrade to an Imax 2000 which has a 2.9dBi gain, my transmitted ERP should go up to 54W.
So, in retrospect by changing coax and removing a few coax ends and a low pass filter, I'm gaining 3.5dB over my current "old" setup.
Does everything gee and haw?
