Quote:
Originally Posted by Tower Guy
I'd say that your problem is caused by high losses.
The 8 way splitter has about 11 db loss, the two way splitter has another 3.5 db. The downlead has about 2 db and the interconnect cabling adds another 2 or so.
Total loss 11 + 3.5 + 2 + 2 = 18.5 db. The typical tuner has a noise figure of 10 db. The 4220 has roughly 6 db gain. The predicted NM in your installation is 22.5 db. KNSD has a NM of 25.4 db. There's about 3 db missing somewhere, but that doesn't really matter much.
I'd replace the 8 way splitter with 6 ports terminated with a two way splitter. You should gain about 7 db.
The next improvement to contemplate would be an antenna upgrade to an HD1080. That antenna is optimum for you because it has a VHF pattern that's backwards from the UHF pattern, which is exactly the direction of your VHF stations. The UHF gain is also a bit higher than your 4220.
Finally, consider a AP4700 preamp. That's a UHF only preamp that bypasses VHF. That's the only amplifier that is appropriate in your situation.
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Thanks for the detailed response. Would this antenna also work for UHF channels? It says it is "VHF antenna".
Also, why would I need VHF only pre-amp? I though channels 2-18 were VHF. The channels I"m having trouble with are at 23 (CW), 40 (NBC) and 51 (KBNT)