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Channel Master TV CM 7400 HD DVR - OTA, Clear QAM, Internet Content - Page 49

post #1441 of 1996
Quote:
Originally Posted by MFOC32563 View Post

There's real voodoo (not VuDu) involved with getting all your OTA gear to work well. I went through three antennas and two or three amps (which now I don't need) before being satisfied with the reception.

I was so sick of dealing with expensive and ineffective antenna options that I went the do-it-yourself route and built one out of plywood and copper wire, and it's been the best antenna I've ever used. Many commercial antenna solutions are overpriced for the low-quality service they provide.

As long as none of your local stations still use the low VHF channels (most are UHF with a few in the high VHF range), a simple home-made antenna easily outperforms the kind of thing you can get at electronics stores. If you're in an area with weak enough signals to require a roof-mounted antenna, it may still be more practical to buy one, but areas with good reception can get by with a simpler approach.
post #1442 of 1996
Quote:
Originally Posted by Donald1800 View Post

Just a note to CM7400 owners from a PALdvr owner (same unit, different Brand) that the fan speed CAN be increased so that the heat felt disappears, increasing the lifespan of all components.....

I don't think the CM7400 has an internal fan . . .
post #1443 of 1996
Quote:
Originally Posted by WS65711 View Post

I don't think the CM7400 has an internal fan . . .

And I don't think the 7400 shares any genetic material with the DTVPal or 7000.
post #1444 of 1996
Quote:
Originally Posted by JoeKustra View Post

And I don't think the 7400 shares any genetic material with the DTVPal or 7000.

No, it is a completely different box with a completely different tuner. The tuner in the DTVPal/CM7000 was better.
post #1445 of 1996
Quote:
Originally Posted by WS65711 View Post

I don't think the CM7400 has an internal fan . . .

I did tear down and found none of them inside of the 7400 model.
post #1446 of 1996
Quote:
Originally Posted by Chuck44 View Post

The Pal and the 7400 are totally different.
The Pal was made by EchoStar. The 7400 I'm pretty sure by a different company.

After reading posts around #1000 and down you should be confident.
post #1447 of 1996
Sorry, you're barking on wrong tree.
Quote:
Originally Posted by Donald1800 View Post

Just a note to CM7400 owners from a PALdvr owner (same unit, different Brand) that the fan speed CAN be increased so that the heat felt disappears, increasing the lifespan of all components.

After more than two years of faultless operation, my PALdvr failed (F208) with the symptoms of alternating "Downloading Guide" and TV show screen, with non-response to Remote commands caused by the fan speed controller failure and resultant Hard Drive failure.

Besides upgrading to a 1T Hard Drive, I had to hard wire the still functioning fan. I located a GND eyelet on the board to the left of the fan and the fan +12V pin of the fan connector, soldered a wire to each point and connected the fan with small Wire-Nuts through a 200 ohm mini-potentiometer. Adjust the fan speed for the quietest operation that results in no warmth at the air outlet on the right side cover top.

This solved both the cause AND the failure with the added bonus of ~3.8 times the recording space. I am a very happy camper.

I understand that fan speed control is superior with PWM circuitry over the method I used, but I am currently not in a position to manufacture a suitable PWM circuit, and my method was used prior to the modern PWM circuits. Just be sure that the fan speed adjustment is not so low that non-start or erratic fan operation results. A little low fan noise but cool operation is better than system failure, and you won't hear it when the TV is ON.

Donald1800

You'll find pictures of the 7400 after post#1000 .. take a look.
post #1448 of 1996
Thread Starter 
Quote:
Originally Posted by Chuck44 View Post

The Pal and the 7400 are totally different.

Correct.
post #1449 of 1996
Now that I've been in possession of both a Tivo Premier and a CM7400 for a few days, I thought I'd post some comparisons on the two units for people trying to decide between the two. The main thing that I've been trying to compare is the tuners. They are about the same. I seem to get about the same amount of reception interruptions on both units. The main difference is that the interruptions seem to be worse on the Tivo. When the CM7400 has an interruption, it'll just kind of pixelate and keep going. The screen on the Tivo, on the other hand, will actually kind of freeze, so the interruption is more noticeable. This is really apparent on my local PBS channel. It has the worst reception on both units. It's still watchable on the 7400. It will pixellate every couple of seconds, but you still have a constant stream of video. The Tivo is unwatchable on this channel because of the screen freezes every few seconds. It's like watching a slide show. Good thing I don't watch PBS very often. Of course, this may be a YMMV issue depending on personal factors like location, antenna, amplifiers, and wiring.

Something else that I noticed that really surprised me about the two units is that the CM7400 has a smoother video transition in going in and out of the guide. The Tivo has a stutter when doing this. I was really surprised by this since Tivo has been around longer, I would have thought it would be a lot more polished than this.

A couple of good points for the Tivo is that it appears to have better video quality than the 7400. To my eye, anyway. It's hard to quantify this, but the colors seem deeper and richer. Also, of course, the Tivo runs much cooler than the 7400. I think that I'll keep both units through the weekend at least, before deciding which one to keep.
post #1450 of 1996
Quote:
Originally Posted by JasonR View Post

Something else that I noticed that really surprised me about the two units is that the CM7400 has a smoother video transition in going in and out of the guide. The Tivo has a stutter when doing this. I was really surprised by this since Tivo has been around longer, I would have thought it would be a lot more polished than this.

A couple of good points for the Tivo is that it appears to have better video quality than the 7400. To my eye, anyway. It's hard to quantify this, but the colors seem deeper and richer. Also, of course, the Tivo runs much cooler than the 7400. I think that I'll keep both units through the weekend at least, before deciding which one to keep.

Thanks for the objective comparison. I've had both. TiVo is bigger too, but my "polish" level is which would I expect my [sister, wife, mother] to learn faster? I don't know since they each have good points and bad points. I feel the video quality to be equal. The audio output of the TiVo might be a few db higher. Both units are worthy of a look by anyone interested in a DVR. I guess you have the HD interface on the TiVo. It's really slow changing modes and menu options. You can add features, but adding horsepower helps.
post #1451 of 1996
As far as which unit is easier to learn how to use, I would say that the CM7400 is more intuitive, because it behaves like any DVR or other video component that I've ever used, so it's really easy to figure out. The Tivo, on the other hand, seems like they are trying to be the Apple of DVR's and over simplify the controls. The remote doesn't have some buttons that are common on almost any other video component like Menu and Stop buttons, so it takes longer to figure out how to do what you want. Also, the Live TV button and swap channel button are the same button, so everytime that I wanted to watch live TV, I ended up switching the channel, so that was kind of frustrating.
post #1452 of 1996
Quote:
Originally Posted by JasonR View Post

The remote doesn't have some buttons that are common on almost any other video component like Menu and Stop buttons, so it takes longer to figure out how to do what you want. Also, the Live TV button and swap channel button are the same button, so everytime that I wanted to watch live TV, I ended up switching the channel, so that was kind of frustrating.

TiVo button equals menu. Press it twice and you go directly to recordings. Pause equals Stop. Actually Live TV and Enter (Last) buttons serve two separate functions. Having used both I found the interfaces similar to the remotes. With the peanut I could effortlessly bounce around without ever having to move my hand. On the 7400's remote I keep having to shift it to perform various functions. However these differences pale to the usability differences as far as DVR features and I think one would be misplaced to draw any real conclusions based on them.
post #1453 of 1996
Quote:
Originally Posted by JasonR View Post

A couple of good points for the Tivo is that it appears to have better video quality than the 7400. To my eye, anyway. It's hard to quantify this, but the colors seem deeper and richer. Also, of course, the Tivo runs much cooler than the 7400. I think that I'll keep both units through the weekend at least, before deciding which one to keep.

Switch cables to your TV between units and compare.
post #1454 of 1996
Quote:
Originally Posted by Charles R View Post

TiVo button ... Press it twice and you go directly to recordings. . .

Ya learns sumptin' every day around hear . . .
post #1455 of 1996
I recently decommissioned a TiVo Premiere due to poor OTA tuner performance. The CM-7400 locks on to the signal and deals with multi-path issues better, almost as well as my Samsung Plasma TV's tuner. I live in the Capitol Hill area of Seattle at the crest. Due west of me are the major networks blocked only by a couple of trees. Since my unit faces north the signals are bouncing off a neighbor's house and the trees. I have a Terk HDTVa indoor antenna, the amplifier is disabled. I've had the unit running now for a week through a variety of weather conditions and it's performance has been great. The CM-7400 breaks up probably about 95 percent less than the Premiere.

I subscribed to the premium guide mostly for the new/repeat episode data. The DVR portion produces excellent quality recordings. The playback looks like live TV, most of the channels I receive are HD so this was an important issue for me.

The box does run warm but no warmer than my Apple Time Capsule or Airport Extreme neither of which have fans. The former does have a hard drive and both work on the same passive cooling philosophy.

I like the UI, it's simplistic and well laid out. One great difference is the lack of advertising. TiVo is overloaded with ads and CM has none. I get enough advertising with the commercials, I don't need more interjected into the UI.

The remote is awkward for some functions, I would use it more if I could get it to control the volume on my AVR but even after a full search of all codes it was a no go. I do have a Harmony 900 so thats not a big deal.

The only oddites I've found so far is the skip forward function will sometimes advance to the end of the recording after a couple of presses. Also the unit is slow to respond to the dot key. 7.1 and the like often sends the tuner to 71 which I don't have so I end up on a Spanish language channel.

Overall I'd rate the CM-7400 a 9 out of 10.
post #1456 of 1996
I have to agree with you about liking the clean, simple UI of the CM7400. The Tivo's UI just seems too busy. Also, a tip on the dot button. I've found that you have to press it twice for it to register. So once you get used to that, you shouldn't have any problems going to the channel that you want. Also, in my comparison of the Tivo and CM7400, I've found another point in favor of the 7400. It boots up a lot faster than the Tivo. I was re-arranging the plugs on my surge protectors and plugged them in at about the same time. The 7400 was up in just a couple of minutes, but the Tivo took at least 10-15 minutes to boot. I didn't time it, but once the 7400 came up, I would watch it for a few minutes and then switch over to the Tivo to see if it was ready and then have to switch back to the 7400. I had to do this several times before the Tivo was ready. That would be really annoying if you were trying to watch something on Tivo and the power got knocked out during a storm.
post #1457 of 1996
Quote:
Originally Posted by JasonR View Post

A couple of good points for the Tivo is that it appears to have better video quality than the 7400. To my eye, anyway. It's hard to quantify this, but the colors seem deeper and richer. Also, of course, the Tivo runs much cooler than the 7400. I think that I'll keep both units through the weekend at least, before deciding which one to keep.

Switch cables between units (ends connected to each DVR) and see if any difference... to eliminate any effects from connectors and TV settings.
post #1458 of 1996
Quote:
Originally Posted by JasonR View Post

That would be really annoying if you were trying to watch something on Tivo and the power got knocked out during a storm.

Can you spell UPS? They cost so little for the amount of frustration they eliminate.
post #1459 of 1996
Quote:
Originally Posted by hdfatboy2003 View Post

I recently decommissioned a TiVo Premiere due to poor OTA tuner performance. The CM-7400 locks on to the signal and deals with multi-path issues better, almost as well as my Samsung Plasma TV's tuner. I live in the Capitol Hill area of Seattle at the crest. Due west of me are the major networks blocked only by a couple of trees. Since my unit faces north the signals are bouncing off a neighbor's house and the trees. I have a Terk HDTVa indoor antenna, the amplifier is disabled. I've had the unit running now for a week through a variety of weather conditions and it's performance has been great. The CM-7400 breaks up probably about 95 percent less than the Premiere.

I subscribed to the premium guide mostly for the new/repeat episode data. The DVR portion produces excellent quality recordings. The playback looks like live TV, most of the channels I receive are HD so this was an important issue for me.

The box does run warm but no warmer than my Apple Time Capsule or Airport Extreme neither of which have fans. The former does have a hard drive and both work on the same passive cooling philosophy.

I like the UI, it's simplistic and well laid out. One great difference is the lack of advertising. TiVo is overloaded with ads and CM has none. I get enough advertising with the commercials, I don't need more interjected into the UI.

The remote is awkward for some functions, I would use it more if I could get it to control the volume on my AVR but even after a full search of all codes it was a no go. I do have a Harmony 900 so thats not a big deal.

The only oddites I've found so far is the skip forward function will sometimes advance to the end of the recording after a couple of presses. Also the unit is slow to respond to the dot key. 7.1 and the like often sends the tuner to 71 which I don't have so I end up on a Spanish language channel.

Overall I'd rate the CM-7400 a 9 out of 10.

Sounds like you would really benefit from a decent outdoor antenna, if possible in your situation. I was having all kinds of difficulty with my indoor antenna reception untl I bought a Channel Master 4228 panel antenna. Now i get perfect reception (except in heavy weather-rain/snow/ice).
post #1460 of 1996
Quote:
Originally Posted by qz3fwd View Post

Sounds like you would really benefit from a decent outdoor antenna, if possible in your situation. I was having all kinds of difficulty with my indoor antenna reception untl I bought a Channel Master 4228 panel antenna. Now i get perfect reception (except in heavy weather-rain/snow/ice).

One of that size is not a possibility. I live in a condo, my front door is on the north side of the building with a fenced in yard. The signals come from in between our bldg and the house next door - maybe only 15 ft separate us. I tried mounting an outdoor antenna on the fence temporarily but the signal was almost non-exsistant.

I truly get a better signal from an indoor antenna ... who da thunk ...
post #1461 of 1996
Quote:
Originally Posted by wajo View Post

Switch cables between units (ends connected to each DVR) and see if any difference... to eliminate any effects from connectors and TV settings.

I thought about that, but I'm actually using the cheaper quality cables on the Tivo, so I don't know if switching them would make any difference, other than making the Tivo look even better than it already does.

Quote:
Originally Posted by JoeKustra View Post

Can you spell UPS? They cost so little for the amount of frustration they eliminate.

That's a good suggestion, although I would have to weigh the benefit against the cost. Off the top of my head, I don't think that my power goes out often enough to warrant having one. Maybe just a couple times a year, but out of curiosity what UPS would you recommend? Also, what is the cost, how many devices does it support, and how long can it sustain power during an outage?
post #1462 of 1996
Quote:
Originally Posted by JasonR View Post

I thought about that, but I'm actually using the cheaper quality cables on the Tivo, so I don't know if switching them would make any difference, other than making the Tivo look even better than it already does.

I guess you'll never know then. Lots of "cheap/bad" cables have been the "BEST" when people compare them. I remember one user who found his $1.97 cable was best of 5, including an expensive Monster cable.
post #1463 of 1996
Quote:
Originally Posted by JasonR View Post


That's a good suggestion, although I would have to weigh the benefit against the cost. Off the top of my head, I don't think that my power goes out often enough to warrant having one. Maybe just a couple times a year, but out of curiosity what UPS would you recommend? Also, what is the cost, how many devices does it support, and how long can it sustain power during an outage?

It would be easy to say APC makes the best. I don't know if that is true anymore since there are many good ones out there. For small outages, and most are, you can easily power the DVR (either one) and your TV for several minutes with 450VA. Of course you turn off the TV when the power fails. The DVR, if recording, may finish. I would also have my network devices on a UPS since the power up sequence from modem to router might be important. Same with any rf amplifiers.

If you have everything fed from a UPS, you can stop using a surge strip since the UPS handles that issue. So that $30 surge strip drops to under $10 for a plain outlet strip.

You can get a feel by using walmart.com and browsing the units. Their return policy could be important. Some UPS units have fans that don't shut off. Some are too sensitive and can't be adjusted.

I have one Minuteman $50 unit that runs my 2160A, and small TV. For my computer and network equipment I have a Cyberpower 1500VA that gives me over 20 minutes. My power company has a great web site. I can use my laptop to get updates when the power fails if my DSL modem or cable modem and router don't die. For my main system I have an APC 1500VA unit with extra battery pack. It powers my AVR, TV (LED-LCD), 515H, Tivo, Blu-ray and three Sony DHG DVR units. I added my 7400, BV-980H and TViX but they are off line right now.

I have bad power. My power company has told me anytime they detect a problem I should expect a six second outage while they test the lines. All of my power lines are on poles and my OTA is just FM. Should I have an outage over 30 minutes I can feed my fridge or heat from a 1500w inverter. It has already paid for itself.

So check out walmart.com and see if anything fits your budget. With free shipping to store you save money since these things are heavy.
post #1464 of 1996
Quote:
Originally Posted by JoeKustra View Post

I have bad power. My power company has told me anytime they detect a problem I should expect a six second outage while they test the lines. All of my power lines are on poles and my OTA is just FM. Should I have an outage over 30 minutes I can feed my fridge or heat from a 1500w inverter. It has already paid for itself.

You gave some good advice, but I have to question the OT bit above. I think a fridge's compressor motor might need a lot of startup current, and anyway a fridge should be able to go without power for several hours (maybe even a whole day) without anything spoiling, if you avoid opening and closing the doors. And do you mean that you can power your gas furnace (blower, etc) from an inverter? I'll have to think about that possibility in case I have an extended outage in the dead of winter. But I can't imagine being able to generate enough heat to keep pipes from freezing, etc, by powering an electric heater from a UPS. Maybe you could get by if you had several big UPS units powering several heaters. Even then I would think the time would be very limited.
post #1465 of 1996
Quote:
Originally Posted by JasonR View Post

I thought about that, but I'm actually using the cheaper quality cables on the Tivo, so I don't know if switching them would make any difference, other than making the Tivo look even better than it already does.

I guess I missed the part as to how you are connected. Is it via digital HDMI or analog cables. If it's through HDMI, as long as it works switching cables would have little impact on PQ. Analog is another story.
post #1466 of 1996
Quote:
Originally Posted by L David Matheny View Post

You gave some good advice, but I have to question the OT bit above. I think a fridge's compressor motor might need a lot of startup current, and anyway a fridge should be able to go without power for several hours (maybe even a whole day) without anything spoiling, if you avoid opening and closing the doors. And do you mean that you can power your gas furnace (blower, etc) from an inverter? I'll have to think about that possibility in case I have an extended outage in the dead of winter. But I can't imagine being able to generate enough heat to keep pipes from freezing, etc, by powering an electric heater from a UPS. Maybe you could get by if you had several big UPS units powering several heaters. Even then I would think the time would be very limited.

Yeah, it's not too relevant [even though the 7400 would make a nice foot warmer].

A UPS cannot power a fridge or house HVAC due to high startup current. For an inductive load you must have a pure sine wave inverter. For a resistive load (area heater) a cheaper modified sine wave inverter is fine. One marine deep cycle battery comes in at 70 pounds. I have a smaller one too. Also, I can heat my house with a gravity valve override, so no circulator motor needed. I have radiators but expect to move soon and will have to contend with hot air issues.

I guess I'm nuts about good power for my entertainment stuff. I never have to content with those nasty micro-outages that seem to cause people to search for the reset commands. I was not pro-active in this area until 1989 when I was in SF during the World Series. Loss of power due to an earthquake seems more of us will need to prepare for in the future. I like my stuff so I give it all the protection I can. The 7400, like most DVRs, is always running.

As for pipes, remember that heat rises. A pipe with warm water doesn't freeze. Before we get smashed, I use gmail mostly. And sorry, but I can't go 12 hours without opening my fridge/freezer. Benchmark: pure sine wave feeding 500 watt resistive load lasted 90 minutes. It took 8 hours to recharge the battery. This was just a test.
post #1467 of 1996
Quote:
Originally Posted by JoeKustra View Post

I guess I'm nuts about good power for my entertainment stuff.

Me too. Having worked many years installing and setting up home theater systems and related gear, I've always been surprised at how many folks are willing to spend thousands on excellent gear but are reluctant to spend a little more on Uninterruptable Power Supplies. IMO there's no better surge protection than a UPS, and the added benefit of having no recordings lost or interrupted is just icing on the cake.

With my TV and AV receiver turned off, a 650w unit on the EC will power everything else up for days. I'm a big fan of APC UPS's, but surely others also make quality units.
__________________________

As for running temperatures on the 7400, after what several posted here about laptop coolers I went looking for one but didn't find any that had their own separate power supplies -- USB only. Then I remembered I had a 6" fan with a clamp at home, and since my EC isn't enclosed I was able to clamp it onto a shelf and aim it at the 7400.

Before I did this I used an accurate IR temp gauge to measure temps. My 7400 was already sitting raised up ¾" on blocks. Highest temp seen was 118F, around the middle-left side of the top of the case. With the 6" fan running at the lowest speed, case temps dropped to ambient room temp, about 74F.

Performance differences I could perceive are minor, but they're there, mostly amounting to a slight improvement in response to remote inputs on nearly all menu screens. Time will tell if other issues show themselves improving.

The differences are minor enough for me to be unconcerned about a customer having one run at 118F, but when a small fan improves performance even a little bit -- and considering that virtually all electronics would choose to run cooler if given the choice -- what the hey... the fan stays.
post #1468 of 1996
Quote:
Originally Posted by BenCartwright View Post

I remembered I had a

Well, at least you thought you remembered.
post #1469 of 1996
Quote:
Originally Posted by Rammitinski View Post

Well, at least you thought you remembered.

Lost me interwebs for a few.
post #1470 of 1996
Quote:
Originally Posted by BenCartwright View Post

The differences are minor enough for me to be unconcerned about a customer having one run at 118F, but when a small fan improves performance -- and considering that virtually all electronics would choose to run cooler if given the choice -- what the hey... the fan stays.

I started to design a cooler for my 7400. Fans, almost all, run on 12vdc. Power can be found using wall warts on equipment you will probably never use again, like cat5 hubs. Sometimes an AVR will have a "trigger" output of 12v. Radio Shack sells the cable and the female two wire connector. My AVR lets me keep the trigger always active. The small 12v power supplies are better and you just need to cut the end off to have a source of 12 volts. I was looking forward to making an enclosure or pedestal to keep the 7400 happy and add some warmth to my room. My last TV used ccfl and was pretty warm. Now the LCD-LED TV is almost cold. A temp of 118F is not that warm, but I would rather see 95F. My youngest Sony DVR HDD is 102F and has over 30k hours on its hard disk.

There are thousands of fans on ebay for under $10. A laptop cooler is good too, just not as much fun.
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