Looking for CM7777 with Two Inputs

[BikingBrian]

I plan to have separate VHF and UHF roof mounted antennas (VHF and UHF signals from different directions) and would like to use the Channel Master 7777 preamplifier. But I wasn't happy to see that the new CM7777 only has one input instead of two. I know I can combine the VHF and the UHF with a UVSJ, but I'd rather not have to do that on the rooftop. Is the older version of the CM7777 with two inputs still out there somewhere?

[GroundUrMast]

I suspect Channel Master has opted to reduce the cost of manufacturing a penny or two... Hence the ad copy on their website "New & Improved". (... meaning improved profit margin for them??)

If you are set on a CM7777, my best suggestion would be to search the big online auction website(s).

CM product documentation has been getting harder to find over the last few years and what is available often leaves me unable to make a informed comparison to other vendors competing product. The spec. sheet for the CM777x (http://support.channelmaster.com/attachments/token/tqnyljazpdg4uhb/?name=CM777x%20Preamplifier%20Data%20Sheet.pdf) for example, does not offer any information re. noise performance beyond the ambiguous claim of 'low'.

The performance numbers of the Winegard and Antennas Direct products are available... If you must have a two input option, the Winegard AP2870 is available at: http://www.winegarddirect.com/viewitem.asp?d=Winegard-AP-2870-Chromstar-2000-Series-Pre-Amplifier-%28AP2870%29&p=SAP2870.

The noise figure of the Antennas Direct PA-18 is spec'd at less than 2 dB. Which makes it a very good choice if you need to use an external UVSJ at the antennas.

[BikingBrian]

It's too bad the Winegard AP2880 is discontinued. I don't think the extra VHF gain could hurt, given my TV Fool report:

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d134977ba17f9d9

The Winegard AP8275 seems like a good deal (price-wise at least), if I end up going with a UVSJ at the antennas anyway, would the AP8275 be OK?

http://www.winegarddirect.com/viewitem.asp?d=Winegard-AP8275-Chromstar-2000-Series-VHFUHF-Pre-Amplifier-(AP8275)&p=AP8275

[GroundUrMast]

Though I'm partial to the PA-18 for it's 1.8 dB noise figure, the AP8275 is only 1 dB worse... not much in the grand scheme of things.

Bear in mind that amplifier gain is not the same as antenna gain. The amplifier is not going to improve the reception 'ability' of any antenna. Amplifier gain can only 'push' the signal through the losses in the cable and splitters that are attached to the output of the amplifier. Any amplifier gain over and above the losses in your distribution cables and splitter is not going to improve your picture quality... unless you have a tuner with a poor noise figure.

100' of RG-6 and a 4-way splitter are going to have a total of 12 to 15 dB loss. My point is that while it probably won't hurt to have 29 dB gain, 17 dB is enough in your case.

[BikingBrian]

OK, gotcha. I'm looking at 100 feet total of RG-6 and one splitter. So for any of those amplifiers the gain will be enough, but it sounds like low noise would be best. I'm seeing conflicting numbers on the AP-18, 1.8 dB or 2.8 dB depending which website I'm looking at. I also share your frustration when manufacturers such as Channel Master do not list meaningful specs.

[GroundUrMast]

@ADTech was helpful, answering this question some time back...

http://forum.tvfool.com/showthread.php?t=905


All amplifiers are going to add some noise to the signal. Better amplifiers add less noise.

[Electron]

I recommend use a weather protected UVSJ = UHF/VHF Separator/Joiner from Antennas Direct.

Use the ->New<- Channel Master preamp.

[klw123w]

I don't know the noise specs (or anything else about this -complete newbie here), but I just got the RCA TVPRAMP1R Outdoor Antenna Preamplifier, (from Amazon) and it has separate VHF and UHF inputs, and a switchable FM trap ...