I'm new to radio and I'm looking to accomplish 3 things (in order of importance)
1. Get OTA HD TV signals- I'm in Roseville-about 35 miles from the source in Sac
2. Receive 800mhz trucked local emergency services systems on my Uniden 436HP
3. Receive Ham traffic once I get my Ham license.
Dedicated TV antenna will be required if you want to get the most out of your TV. You don't need a lot if you have a clear shot into Sacramento and south. Important part is to get the antenna up in the air and away from surrounding structures. Connect it with RG-6 or RG-6QS cable.
For 800MHz receive, it really depends on how far off the tower is you are trying to hear. A dedicated 800MHz Yagi will often work very well if all the stuff you want to listen to is in the same direction. An 800MHz vertical will work if there are multiple locations you need to hear (different tower sites). A discone can be a good option, as they'll usually cover VHF, UHF, 700MHz, 800MHz and higher. Drawback is that they have zero gain, so they generally are poor performers unless you have strong signals to deal with. Coax cable is important, too. You need to get as much signal as you can down the cable to your radio. Cheap/low grade coax has a lot of loss, and can reduce the received signal so much that your radio will not decode. Higher grade coaxial cable is usually a must unless your radio and antenna are close together.
Considering your location, I would not limit yourself to just 800MHz. With a good multiband antenna, you'll hear a lot of VHF and UHF traffic. Add low band if you want to listen to CHP.
I don't know a lot about antennas, my question is-is there 1 antenna that can accomplish all these tasks i.e. One of those uhf/vhf channel master antennas.
No, you'll need separate antennas for TV and the scanner. While you can make them work, there are a few challenges you'd have to overcome, and personally, I don't think it's worth it. Separate antennas will serve you much better.
Is it best that I get a yagi style antenna for my scanner and get a separate antenna for the TV?
Yes. TV signals are horizontally polarized and so are the TV receiver antennas. The stuff you want to listen to on your scanner will be vertically polarized, and your scanner antenna will need to be also. There are ways to make a TV antenna work as a scanner antenna, however it requires turning them on their side, which would impact the TV receive performance.
I would like to mount these antennas in my attic-although there may be an option for a roof mount, but this would be less desirable. Thanks for your help!
Mounting in the attic can work, however there are some things you need to consider:
Any metal in your roof can block the radio signals. If you have a metal roof, mounting in the attic greatly reduce performance.
Even vapor barrier in the insulation can cause issues, but the insulation is usually below where you'd mount the antenna.
For antennas like these, height is key. The higher the antenna is, the farther it can "see". Since VHF, UHF, 800MHz, etc. are generally "line of sight", your antenna needs to be able to see the source to work well. The higher the antenna is, the farther off the radio horizon is. Lower antennas will not perform as well as one that is higher up.
When you get your amateur radio license, transmitting from an antenna in your attic can cause some interference issues if your transmitting antenna is close enough to phone wiring, power wiring, TV antennas, as well as appliances in your home. Again, getting the antenna outside is best.
Use high quality coaxial cable and pay very close attention to waterproofing outdoor connections.
