Power amp recommendation

[comfortably_numb]

Do you guys think I should forget about the CM-777 and get an in-line amp instead ?
Maybe the CM-7777 is overkill and is causing some of the problems?
Also I have heard the because the BOLT splits signal over 4 tuners that it weakens it.
Is there a way to avoid that?

Mark

The CM-7777 is a preamp for extremely deep fringe reception. Even one high power station in your area can cause noise on your target station(s) when using that preamp. You have many high power stations in your area, so that preamp is going to cause problems. As others have also mentioned, you really don't need it. If picking up San Francisco stations is the goal, point a directional antenna toward that area, try it without a preamp, then with a medium-power preamp, like the CM-7778 or the RCA TVPRAMP1Z ($25 at Walmart).

 

[David Taber]

The CM7777 is one of the hottest amps around (yes, you can do 6 dB better...but I'm not sure signal strength is your real problem).
The BOLT has an internal splitter that will reduce the input at each tuner by around 6 dB. But I'm not sure weak signal is the problem.
Try removing the preamp and see if it helps any. If that is way worse, leave the preamp in place but add a signal splitter to attentuate the signal (a 2-way splitter reduces the signal 3.5 dB)--may solve the problem.
I suspect that your real issue is interference from Sacto stations...and what the points to is a poor front/back ratio in your antenna. You say you've got an "advantage" -- is that the Channel Master? You might want to call them up and ask if there's anything you could add (wire mesh?) to improve that.
You didn't mention an antenna rotator: I'd add that right away, given how crowded your TVfool map is. Also, there may be some other powerful non-TV sources of interference that are swamping the TiVo. Consider getting a low-pass filter (they're cheap) that attenuates everything above 700 MHz (like, cell towers...poice/fire/aircraft radios...). If there is a really big FM transmitter within a couple of miles of you,you should look into an FM or other low-pass filter (everything below 174 MHz)

 

[harshness]

Somewhat random thoughts:

• If you plan on using the TiVo, it doesn't really matter what your TV tuners are telling you.
  
• Unlike TiVos of yore, the newer (HD capable) models can't use external sources.
  
• Sometimes when the signal is split too many ways, a distribution amp may be of more help than a preamp as they are designed more to compensate for losses than radically boost the signal.
• The only way to get around splitting the signal so many ways is to use a DVR with less total tuners as all TiVos have only one input for OTA.
• Using a DVR in conjunction with DXing is typically not going to yield a stellar result. The fact that you're dealing with one or more edges (electromagnetic speed bumps) only makes it worse (more weather and environment dependent -- generally unpredictable).

 

[comfortably_numb]

• Using a DVR in conjunction with DXing is typically not going to yield a stellar result. The fact that you're dealing with one or more edges (electromagnetic speed bumps) only makes it worse (more weather and environment dependent -- generally unpredictable).

This couldn't be more on-point. While I have been able to (rather) successfully tune some deep fringe VHF stations on a regular basis, they aren't reliable enough for recording purposes.

If the OP wants to try and receive SF stations for sh*ts and giggs, then more power to him. But I think those of us who have gone down the road of trying to receive extremely distant stations reliably on a regular basis know the challenges associated with that.

 

[Jim5506]

Update:
My antenna is exactly 35' above ground. clear sight with no trees etc.
My issue is that I get a local channel KCRADT just fine of course.
But another bay area channel KGO35-DT comes in at the same signal strength but no video.
I realize that there is a great difference in distance. Just wondering if the signal strength is the same why I am not getting the video.

Here are pics of both:
View attachment 130727 View attachment 130728

3-1 and 7-1are on the same frequency channel, so if you receive one the other is also received.

It appears the station is not providing signal to the 7-1 sub channel.