Corpus Christi, TX: Channel Master CM7777 OR CM7778 - AVS Forum | Home Theater Discussions And Reviews
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post #1 of 10 Old 08-11-2019, 09:35 PM - Thread Starter
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Corpus Christi, TX: Channel Master CM7777 OR CM7778

What happened to these preamps? Mine finally crapped out on me after 17 years. Now I can't find one, not even used!

It's like they all disappeared. Can't even keyword it on eBay. And they are out of stock everywhere!

Anyone have one hiding in their stash they want to sell me? 😂
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post #2 of 10 Old 08-12-2019, 05:44 AM
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Quote:
Originally Posted by bsr2002 View Post
What happened to these preamps? Mine finally crapped out on me after 17 years. Now I can't find one, not even used!

It's like they all disappeared. Can't even keyword it on eBay. And they are out of stock everywhere!

Anyone have one hiding in their stash they want to sell me? 😂
Hello, bsr2002

They are back ordered and hard to find.

Channel Master still shows the CM-7777HD Amplify in stock. It is a good preamp in a poor enclosure for outdoor use. I use it as an instrumentation amp for testing.
https://www.channelmaster.com/Amplif.../cm-7777hd.htm

The 7777 has gone through many design changes. Even if you could find one I would advise against it; it is too easily overloaded by strong signals. It has only one antenna input. The original 7777 was a good amp with two antenna inputs, one for UHF and one for VHF, if needed.

The best currently available preamp for your location would depend upon your signals. I would need to see a signal report for your location in the Flour Bluff section.

a TVFool report for Waldron Rd and Purdue Rd would look like this:
http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d903812cf2647e c

a rabbitears.info report for that location would look like this:
https://www.rabbitears.info/searchmap.php?request=result&study_id=4041


Very strong signals there; wouldn't think you would need a preamp with an outdoor antenna

but you might not live near there

if you do, I would suggest the Antennas Direct Juice preamp.

If you can not measure it, you can not improve it.
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Last edited by rabbit73; 08-12-2019 at 07:06 PM.
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post #3 of 10 Old 08-12-2019, 06:45 AM
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I heard there were some issues with them failing... Maybe they pulled them? I would hope they would return with the issues resolved if this is the case...
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post #4 of 10 Old 08-12-2019, 01:49 PM
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He my be referring to the original dual input versions of the CM-7777 and 7778 preamps. They were good preamps but unfortunately no longer available. But what is confusing, Channel Master used the same model numbers for the newer versions. The new 7777 has one input and 30db gain, and overloads very easily unless in a deep fringe application. But the newer 7777HD-Amplify is a good preamp with adjustable gain, although there is some concern about outdoor use. And their newest 7778HD-Amplify Pro Grade brings back the dual inputs and a good outdoor design. It also has adjustable gain and an FM trap. That would likely be the best replacement, although it is expensive at $99. The new Channel Master Pro Grade preamp is good, despite the confusing marketing and model numbers.
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post #5 of 10 Old 08-12-2019, 04:08 PM
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The 7778HD Amplify+ and 7778 are out of stock on the CM site. There is a US dealer that says they have a 7778HD for $130.

Some of the dealers in Canada say they have the 7778 with one input in stock.

If you can not measure it, you can not improve it.
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Last edited by rabbit73; 08-12-2019 at 04:39 PM.
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post #6 of 10 Old 10-15-2019, 07:11 PM
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Quote:
Originally Posted by rabbit73 View Post
The 7778HD Amplify+ and 7778 are out of stock on the CM site. There is a US dealer that says they have a 7778HD for $130.

Some of the dealers in Canada say they have the 7778 with one input in stock.



The 7777 is back in stock. I just ordered version 3 of the 7777 direct from the Channelmaster website.
I emailed SolidSignal about it and they said that CM revoked third party dealers(?!) and is only selling them directly now.



I am in a very signal poor rural location and I am not worried about any overload. Definitely I would be cautious if you are anywhere near civilization (unlike me)!
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post #7 of 10 Old 10-16-2019, 07:35 AM
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Originally Posted by ab8jh View Post
The 7777 is back in stock. I just ordered version 3 of the 7777 direct from the Channelmaster website.
Thanks for letting us know about the 7777V3. I'm glad they added "V3"; it was getting difficult keeping all the 7777 versions straight. I notice they are using the reviews for the previous 7777.

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I emailed SolidSignal about it and they said that CM revoked third party dealers(?!) and is only selling them directly now.
That's pretty weird, I wonder why CM did that.
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I am in a very signal poor rural location and I am not worried about any overload. Definitely I would be cautious if you are anywhere near civilization (unlike me)!
The 7777V3 is rated at a gain of 26 dB. The previous 7777 with the single antenna input (V2?) was 30 dB, but when I measured the gain of the one they sent to me, it was 25 dB. I think they made a silent design change because they had so many returned by unhappy users.

Yeah, you are in a poor location for OTA reception.
http://www.tvfool.com/?option=com_wr...903804dc8c8720

Can you receive WTRF?

report from rabbitears.info:
https://www.rabbitears.info/searchma...study_id=19715

extract from that report:



If I click on the Transmitter Distance for WTRF in your rabbitears.info report, I see there are a lot of hills in the signal path:

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If you can not measure it, you can not improve it.
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www.megalithia.com/elect/aerialsite/dttpoorman.html

Last edited by rabbit73; 10-16-2019 at 08:08 AM.
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post #8 of 10 Old 10-16-2019, 02:00 PM
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Yes WTRF comes in nicely with a Stellar Labs 30-2476 VHF-Hi yagi. WTOV is a little trickier and the report you generated confirms that. As is the case in bad terrain in fringe areas, tvfool and rabbitears are only rough approximations of actual signal reception conditions. VHF is much better for tv here due to the terrain in eastern Ohio.



I found a gap through the trees and hill to my due west, and am going to try for WCMH/WBNS. They both seem to be about -20dB down and between the gain of a dual bay Hoverman and CM7777v3 I may have a shot. In this part of Ohio hilly terrain and leafy green foilage are my biggest enemies besides the 80 mile distance to the transmitters.
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post #9 of 10 Old 10-24-2019, 08:24 PM
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I received the new CM7777v3 last week, and I tried it with my dual bay gray-hoverman for Columbus stations with no success. However, its doing quite well on my Stellar Labs deep fringe vhf-hi beam. It picks up the two vhf-hi stations in my area well along with a vhf-lo and two uhf stations nearby. I'm not sure about how it compares to the old CM7777, but I'm impressed with it so far.
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post #10 of 10 Old 10-25-2019, 05:55 AM
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Quote:
Originally Posted by ab8jh View Post
I received the new CM7777v3 last week, and I tried it with my dual bay gray-hoverman for Columbus stations with no success. However, its doing quite well on my Stellar Labs deep fringe vhf-hi beam. It picks up the two vhf-hi stations in my area well along with a vhf-lo and two uhf stations nearby. I'm not sure about how it compares to the old CM7777, but I'm impressed with it so far.
Wow, you are in a dead spot for sure.
Luckily WTRF's pattern tends to go further toward the west since decades ago the top of the tower got slightly bent to the east in high winds.
I was there for a stationmaster install at the 500 foot level and you could clearly see the top section slightly canted eastward above that level.
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