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Discussion Starter · #1 ·
I get a decent signal on MOST OTA channels in my area (around Chicago). But there are a few that can be iffy. Use a Bolt, couple Roamios and a Premiere. Am curious about adding an amp/preamp to my antenna (it's an outdoor antenna that I use indoors, not one of those flat indoor window things). Will be using a 3-5 way splitter somewhere along the line (maybe the type/brand of splitter makes a difference too, different for OTA vs cable or satellite?) Any reasonably priced methods? I've seen talk about preamp which goes right at the output of the antenna, then amp and power inserter (not sure about amp/preamp terminology either, the units I see for sale just say in-line amplifier). Not one of my areas of expertise. Here is something one seller at ebay has with a picture of how to hookup (40db total, maybe I don't need that much?) Power inserters, there seems to be cheap DirecTv power inserters for sale, would they work ok for OTA antenna even though DirecTv stuff is for satellite, that part seems to add power to the setup only? Any recommendations would be appreciated. Maybe try the 10db preamp at the antenna output with the power inserter near the splitter by the Tivos, then add the other amp if that is not enough? Oh, no I don't want to move the antenna outside, too many wiring issues.

40dB EXTREME GAIN TV ANTENNA PRE-AMPLIFIER & SIGNAL BOOSTER | eBay
 

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There's a lot to take into consideration. How far are the broadcast towers. Are they all in the same general direction. Do they broadcast on UHF 14 or higher, VHF 2-13. Be aware that legacy channel numbers, ie NBC4 may actually be broadcasting on ch22. Too bad you can't move the antenna outside so you have the clearest possible view toward the broadcast towers. You are at a disadvantage immediately. Building materials, tree foliage etc reduces signal strength greatly. A pre amp cannot make up for a signal that isn't there because of antenna location. The purpose of a pre amp is to make up for signal loss due to long coax cable runs (6dB loss for every 100') and also signal loss from splitters. Two way splitter -3.5dB, four way splitter -7dB. Cheap pre amps may be very noisy and actually make the reception problem worse. A pre amp that is too strong can also make things worse. 40dB pre amp is probably huge overkill. Again, your signal chain starts with the antenna and relies on every single connector, length of coax, device to handle the signal properly. One mistake and you can have problems.

You asked specifically about pre amps. I am using an Antennas Direct CPA19 pre amp, (17dB). The pre amp is located within three ft of the antenna. The power inserter (puts 12-15v DC on the coax to power the pre amp) is located at the main TV 40' from the antenna. Also at the main TV is a three way splitter to feed my TV tuner and my Tivo. Those two ports are marked -7dB. The third port feeds another TV 70' away and is marked as -3.5dB. So the signal loss for my furthest tv is roughly -10dB. (3.5 splitter loss + signal loss for 110' coax 6.5dB=10dB) The 17dB pre amp is a good match and not too strong.

Rabbitears.info is a great website for finding more info about your broadcast towers, actual broadcast channel numbers, compass headings, signal strength etc.

What is the model number of your antenna?
 

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Discussion Starter · #3 ·
There's a lot to take into consideration. How far are the broadcast towers. Are they all in the same general direction. Do they broadcast on UHF 14 or higher, VHF 2-13. Be aware that legacy channel numbers, ie NBC4 may actually be broadcasting on ch22. Too bad you can't move the antenna outside so you have the clearest possible view toward the broadcast towers. You are at a disadvantage immediately. Building materials, tree foliage etc reduces signal strength greatly. A pre amp cannot make up for a signal that isn't there because of antenna location. The purpose of a pre amp is to make up for signal loss due to long coax cable runs (6dB loss for every 100') and also signal loss from splitters. Two way splitter -3.5dB, four way splitter -7dB. Cheap pre amps may be very noisy and actually make the reception problem worse. A pre amp that is too strong can also make things worse. 40dB pre amp is probably huge overkill. Again, your signal chain starts with the antenna and relies on every single connector, length of coax, device to handle the signal properly. One mistake and you can have problems.

You asked specifically about pre amps. I am using an Antennas Direct CPA19 pre amp, (17dB). The pre amp is located within three ft of the antenna. The power inserter (puts 12-15v DC on the coax to power the pre amp) is located at the main TV 40' from the antenna. Also at the main TV is a three way splitter to feed my TV tuner and my Tivo. Those two ports are marked -7dB. The third port feeds another TV 70' away and is marked as -3.5dB. So the signal loss for my furthest tv is roughly -10dB. (3.5 splitter loss + signal loss for 110' coax 6.5dB=10dB) The 17dB pre amp is a good match and not too strong.

Rabbitears.info is a great website for finding more info about your broadcast towers, actual broadcast channel numbers, compass headings, signal strength etc.

What is the model number of your antenna?
Thanks for info. I'm about 35 miles SW of Chicago. Towers are on Hancock and Willis. Two of my problem stations are VHF high 11 and 12, one of those is CBS. The other two are UHF but 45 to 55 and 32 to 42 signal strength. The 32 to 42 station records ok when 40-42, below that does not record or a load of tiling. My antenna is a Monoprice HD8. I may try something like what you do, or maybe 20dB. Antenna wire about 30 feet to main TV, another 70 feet to 2nd TV. My main concern is most of my other channels have a very strong signal. And I heard using amp can screw that up. Not sure if worth it to possibly gain better reception on 4 channels.
 

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The Monoprice HD8 appears to be a UHF only antenna with no VHF dipoles so I'm not surprised hi VHF is a problem. Antennas Direct makes an add on VHF antenna for hi VHF. It comes with a coax combiner and may give you improved reception for ch11 and 12 or you might want to replace your antenna with one that is specifically made for UHF and hi VHF.

I took a wild guess and pulled this rabbitears.info report for Joliet. It looks like all the channels you'd be trying to get are in one general direction.
RabbitEars.Info

I am 40-45 miles from the broadcast towers. All in the same direction. The antenna I'm using is a Channel Master 4228 which is UHF with hi VHF capability.

Channel Master 4228

I have one VHF on ch12, it comes in great. The current version of this antenna is called the Extremetenna 80. Lots of marketing hype, LOL. It's pretty much the same 8 bay bowtie style antenna. The antenna is outdoor above the roof with a fairly clear view toward the broadcast towers. I am in a valley with two edge reception, meaning the signal has to cross two ridges before it reaches my location. My signal strength on the Premiere is generally above 80 and some channels are almost 100 for the major networks. The Sony TV gives signal strength on a very different scale but the important part is, the Tivo Premiere receives everything the Sony tuner does. And when there's a weird atmosphere event that causes a weaker independent channel to drop out, it happens on the Premiere and the Sony. I have no experience with Roamio or Bolt.
I really think you need to consider a better antenna and place it outdoors. A 20dB or less pre amp for your coax length sounds like a good idea. If you had a very close broadcast tower, the preamp might overload but it sounds like it should work OK. If you have unused splitter ports be sure to terminate them with a cap or you'll lose signal unnecessarily. Ideally, use a splitter exactly the the size for your application.

This is a Clearstream 2 mounted to my camper. The upper horizontal portion is for hi VHF, the figure 8 is the UHF antenna. 45-60 mile reception. Antennas Direct makes an indoor verson of this antenna.
 

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Discussion Starter · #5 ·
Again thanks for all info, very detailed. For now I will try the easiest possibility, a preamp and power injector. Ideally a better antenna and outside but could be moving within a few years so don't want to do anything too much, running wires through walls etc. Plus the majority of the channels I get fine, less than a handful (including locals) that can be suspect.
 
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