Jakeman3, why do you think you have interference from channel 6? According to your TVFool report (in another thread) channel 6 is quite weak (-55.7dBm). I suspect your problems lie elsewhere.

I believe I am getting interferance on channel 6 because... according to my TVfool report, both of the CTV stations in the area are showing significanltly lower signal strength than TVO on channel 6. Now that the 8200 is up an running, both CTV stations are crystal clear whereas TVO channel 6 is definately not. This weekend I will be looking closer at the interferance (what it looks like) to try and determine if it seems to be FM interferance.... If I still think it's FM, then I want to actually test what FM signals that I will actually be losing if I have to test/use the trap on the CM7777..

Oh. Interference on channel 6 not interference from channel 6. FM interference is the most common type of interference for channel 6 specifically. There are several other types of interference on VHF-LO as a whole that don't affect VHF-HI or UHF. The links stampeder provided are a great place to start.

Hey guys, I've been mulling about this type of setup:
https://lh4.googleusercontent.com/_UiD8F79jssM/TbhJlnzNC4I/AAAAAAAACNc/ZWeRWeGPXbE/s576/OTAConcept.jpg

But would like feed back. Basically Target 1 would be Toronto, Target 2 would be Buffalo, based on my TVFool report (viewed here: https://sites.google.com/site/maycreates/ota-setup)

Setup in the attic. Currently my two Hoverman's are combined before a single CM-7777 preamp. Just like some input as to what negative effects (other than the possible overload issue) I could run into if I ran each antenna group on their own preamp, then combined further down the chain prior to distributing to the individual tuners. I may not even require the CM-3414, but just a 4-way splitter (would also help tone down signals if over amplified by the pre-amps).

UHF Antennas would still be my Gray Hovermans, VHF antennas would be some yet to be determined types, but most likely some DIY flavor. I can conceivably see overload issues due to over amplification. Just want some feedback as to whether I'm completely nuts, or if this is conceivable.

Stampeder, if this is not the right area, please move to where it would adequately go. Not sure if this is an amp question, or a OTA area reception question, or a splitter question...maybe it's a little bit of everything.

Marbles_00 your logic looks fine, especially with making sure the power supplies are dedicated to each preamp, but the added boost of the CM3414 distro amp might be overkill.I may not even require the CM-3414, but just a 4-way splitter (would also help tone down signals if over amplified by the pre-amps).Yep, I would try your plan without the CM3414 first (1-to-4 splitter instead) and then if it seems to require the extra oomph go ahead and try the amp but have a few 3dB to 6dB attenuators or some variable attenuators on hand for trimming down the signal at each of the tuners (especially tuner 3!)

Ideally the best practice is to test the signal strength/quality of each tuner based on the total coax length to it. Start with the longest and then go one-by-one to the shortest, in that order. Get the tuner with the longest coax run set "just right" and then attenuate the others in order, as needed. For example, the next tuner might need a 3dB, the next tuner after that 3dB, and the one with the shortest length 9dB (again, just examples). In your diagram the testing order would be 2, 1, 4, 3.

Since not all ATSC tuners perform alike it might even be worthwhile to put your best (most sensitive) tuners on the longest lines if that is at all possible.

Thanks for your input Stampeder.

What about mixing brands of pre-amps (different gains and the sort)? Or is it best to keep as much common as possible to alleviate interference issues?

Marbles_00, my only word of warning is the noise from the two CM7777s will be added together so the results may not be any better than combining the antennas first.

The other thing is make sure the antennas are directional enough that the antennas facing target 1 don't receive any of the same signals the the antennas facing target 2 receives. Signals received by both antennas will likely be adversely affected by combining the antennas.

It would probably be best to test without any amplification at all in order to establish a baseline. Then you could experiment with variations on the theme (both antennas into one preamp, etc. etc.) to find the best solution.

Hopefully that would not entail a trip up a shakey ladder in the wind way up high! :eek:

Well my current setup is in the attic, UHF antennas combined to a CM-7777 preamp input, single antenna to VHF input, single lead down, through a CM-3414 to the four tuners. I have added a splitter to tone down the signal on the short cable. Not the best attenuator, but it is working.

I know from experimenting way back when in aiming the antennas, I connected each one individually through a 20' cable to my HTPC (moved it upstairs for testing, since it was the only thing at the time with an ATSC tuner). After aiming each one, then combining them with a splitter, I lost channels like CFTO, WUTV, and a couple other weak ones.

I was just thinking of this new setup to take out combining the antennas prior to amplification, so I may be able to gain back what I lost when combining, but doing what I can to keep my distribution. I'd also like to target a VHF antenna at WNGS, but at the same time target CFTO RF9, but i don't want to combine the VHF antennas prior before the preamp. I figure I'd knock to much needed gain, then I'd just be amplifying more noise.

if this is the right place

I want to add channel 6 from my vip delphi 302 sr to my almost all channel system based on a cm 4228 .

The pic below is how I think it should work with a join - a -tenna . Is this the way to go , or is there something better ? everything works great right now , just am greedy for 6 ....

4 does not matter as I have 4.1 digital that is really good


http://img.photobucket.com/albums/v493/twister55/antenna/channel6tenna1-1.jpg

GeoStar,

If all you're doing is adding a VHF 6 signal to a VHF 7 and up (including UHF) system, use an HLSJ. They only cost a couple of dollars (before shipping) and don't require any tuning or adjustment.

http://www.hollandelectronics.com/catalog/catalog.php?product_id=Highband-Lowband-Separator-Joiner
http://yhst-18278607509093.stores.yahoo.net/pico-0144.html

OTOH, if you have other low VHF signals to contend with, go with the Jointenna.

Also keep in mind that if, even after those measures, your Delhi VIP302 is still adding unwanted FM Radio interference an FM trap might be required. You won't find out if FM is a problem until you fully assemble your planned system.

In all-in-one solution is the cm7777 or any other dual input preamp which would replace your KT200 and do the antenna joining. In addition, many of those preamps, like the 7777, have an internal FM trap.

I think he's trying to get maximum leverage out of his Kitz 200 though. :)

While i am sure this is not the right thread to discuss it, many in my region have had to put an FM trap in front of the KT200 to get better reception. GeoStart is not exactly close but is in the same region and is likely even closer to the FM tower(s). The added insertion loss of the trap in front of the preamp, in addition to the perceived weakness to static, made the KT200 less attractive to me. So I ended up keeping my own KT200 and switching to the all-in-one, supposedly more reliable cm7777. Always good to hear all the options, even the greenfield rip and replace options even if they are hard to hear...

And when I say better reception, it's for getting better reception across the board, not just for channel 6. Must be an issue with FM stations overloading the KT200 in the Ottawa region.

GeoStar, first of all why use a VIP-302SR if all you want is channel 6? You would be much better off using a VHF-LO wideband Yagi. Alternately, why not use the VIP-302SR for VHF-HI as well, since it is better at it than the CM-4228HD and all VHF channels (Lo and Hi) will be from Camp Fortune post transition. You could then combine the two with an HLSJ.

If you are truly wanting to maximize the benefit of the Kitz 200, connect it directly to the CM-4228 and have a separate pre-amp for the VHF antenna (if needed since it looks like you will also have a distribution amp).

Similar to what roger is saying, except combine both antennas with a UVSJ. The UVSJ will transform your KT200 into a dual input preamp... the 302 would be used for VHF, and the 4228 for UHF, exactly what they are best at.
EDIT: I should also mention that I was getting way better reception on channel 13 on the vip302sr pointed at CF than the cm4228hd pointed to US stations

I was assuming he already had all that stuff in his original diagram. Is that the case, GeoStar, or is there some flexibility in the gear selection?

Given the option flavoie describes, an FM trap would be needed on the VHF side of the UVSJ. The VIP-302SR does have elements to try and reduce FM interference, but I am not convinced they will be enough on their own.

When choosing an FM trap, be sure and get a band shifted one that doesn't affect channel 6. The Winegard FT-7500 is NOT a good choice!