Zenith DTT901 - Page 20 - AVS Forum
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post #571 of 2239 Old 07-18-2008, 10:17 AM
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First Hard Lockup

My DTT901 May build had a hard lockup today...

No response from remote control or front panel buttons
locked on CH 3-1.

I had to remove the power to get back normal function of remote or front panel buttons.

Has anyone else experienced this ?

arch 1
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post #572 of 2239 Old 07-18-2008, 11:40 AM
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Got 2 DTT901 (May builds) from watchdigitaltv.com. Both work great and pull in 15 stations at equal or better quality than analog. Using on old 20" set via rf input.
Remote found the on/off code for the ~20 year old TV.

Happy so far.
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post #573 of 2239 Old 07-18-2008, 01:11 PM
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Insignia NS-DXA1-APT includes with the instructions a separate piece of paper that reads as follows:


-----------------------------------------------------------
For the best picture and sound performance:

...If you only have an RF connection to your TV:

Connect the supplied coaxial cable to the To TV (RF) jack on the back of your converter box, then connect the other end of the cable to the Antenna IN jack of the TV. For the best performance with the connection,

1. Change the Audio Output option to MONO.
2. Set your TV volume at mid-level (half-way between the quietest and the loudest setting)
3. Use the converter box remote to control the volume.
------------------------------------------------------------


If Insignia suggests using MONO, it would appear that there is something wrong with STEREO when using the RF jack. I know with the regular NS-DXA1, the volume was reduced dramatically in STEREO. With the APT, there seems to be no difference in volume between STEREO and MONO. There might be a defect somewhere else, but my brief usage did not reveal it.

Apparently, there is no issue when connecting via RCA jacks.

If anybody knows how I can determine the defect, feel free to post the information. The manual from the Zenith 901 that I have never mentioned anything about switching to MONO. So to be cautious, it might be best to avoid the Insignia APT if there are Zenith 901's in your area.
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post #574 of 2239 Old 07-18-2008, 10:23 PM
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That is because (Sadly...) no CECB to date actually has stereo MTS output on It's RF output!

The sound needs to be combined if you use RF....

The fact that the level decreases indicates a cancelling effect is taking place. That can be caused if the Firmware is telling the Dolby Digital encoder to apply stereo widening enhancements while downconverting to two channel stereo. That makes the RCA line output sound better on regular amplifiers, and assists amplifiers that have surround sound imitation circuits that use phase to do It's job...

I'm open to others input because over the years there have been so many types of phase encoded "Quad" channel protocols I lost track...

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post #575 of 2239 Old 07-19-2008, 06:53 AM
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I have just installed my Zenith DTT901. I am not receiving any low power or translator broadcast. Do I understand correctly, that, to receive low power and translator broadcast, I have to turn off the converter box? Is this how other boxes with analog pass-thru capabilities work?
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post #576 of 2239 Old 07-19-2008, 07:33 AM
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Quote:
Originally Posted by Lamchop View Post

I have just installed my Zenith DTT901. I am not receiving any low power or translator broadcast. Do I understand correctly, that, to receive low power and translator broadcast, I have to turn off the converter box? Is this how other boxes with analog pass-thru capabilities work?

Powered Off or unplugged, DTT901 is 'passing through' any available analog signal.

Powered On, DTT901 is 'converting' any available digital signal.

The Zenith DTT901 provides this relatively easy method of dealing with analog signals.

On the other hand my Magnavox TB100MG9 is VERY klutzy and you do not want to go there!
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post #577 of 2239 Old 07-19-2008, 09:01 AM
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Lamchop, are you getting the major network channels in analog, or just not the low power ones? Are these channels you got OTA before before you hooked up the CECB?

If you have used cable recently, is your tv still set on CATV? For analog OTA, I changed the setting to Antenna (mine calls it "tv"), and did a fresh channel scan.

The way I have my box hooked up to VCR, I get the signal through the VCR, so I need to switch the tv to the Vid setting the VCR is hooked up to, and use the VCR to change channels. One more possibility. :-)
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post #578 of 2239 Old 07-19-2008, 10:27 AM
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Quote:
Originally Posted by WackyPacks View Post

Insignia NS-DXA1-APT includes with the instructions a separate piece of paper that reads as follows:


-----------------------------------------------------------
For the best picture and sound performance:

...If you only have an RF connection to your TV:

Connect the supplied coaxial cable to the To TV (RF) jack on the back of your converter box, then connect the other end of the cable to the Antenna IN jack of the TV. For the best performance with the connection,

1. Change the Audio Output option to MONO.
2. Set your TV volume at mid-level (half-way between the quietest and the loudest setting)
3. Use the converter box remote to control the volume.
------------------------------------------------------------


If Insignia suggests using MONO, it would appear that there is something wrong with STEREO when using the RF jack. I know with the regular NS-DXA1, the volume was reduced dramatically in STEREO. With the APT, there seems to be no difference in volume between STEREO and MONO. There might be a defect somewhere else, but my brief usage did not reveal it.

Apparently, there is no issue when connecting via RCA jacks.

If anybody knows how I can determine the defect, feel free to post the information. The manual from the Zenith 901 that I have never mentioned anything about switching to MONO. So to be cautious, it might be best to avoid the Insignia APT if there are Zenith 901's in your area.

I've had both the Zenith DTT900, and DTT901. Both manuals recommend switching the audio to mono when using the RF out of the converter. With the DTT901 that I have, the recommendation is made on pages 6 and 9 of the manual.

Bottom line--don't worry about it.
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post #579 of 2239 Old 07-19-2008, 11:32 AM
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Thanks for the clarification about the MONO issue.
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post #580 of 2239 Old 07-19-2008, 03:28 PM
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Quote:
Originally Posted by Lamchop View Post

I have just installed my Zenith DTT901. I am not receiving any low power or translator broadcast. Do I understand correctly, that, to receive low power and translator broadcast, I have to turn off the converter box? Is this how other boxes with analog pass-thru capabilities work?

It's most likely that your low power and translator stations are not digital. They do not need to convert to digital after Feb. 17th 2009. Yes, use the pass-through feature to watch them.
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post #581 of 2239 Old 07-19-2008, 07:00 PM
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Quote:
Originally Posted by Lamchop View Post

I have just installed my Zenith DTT901. I am not receiving any low power or translator broadcast. Do I understand correctly, that, to receive low power and translator broadcast, I have to turn off the converter box? Is this how other boxes with analog pass-thru capabilities work?

Make sure you use a good quality RG-6 cable for connecting the CECB to the TV. The cheap cable that comes in the box is not a good performer on weak analog. I noticed quite a difference when I switched the cable on mine. Just a thought
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post #582 of 2239 Old 07-19-2008, 11:11 PM
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Quote:
Originally Posted by Digital Rules View Post

Make sure you use a good quality RG-6 cable for connecting the CECB to the TV. The cheap cable that comes in the box is not a good performer on weak analog. I noticed quite a difference when I switched the cable on mine. Just a thought

Hmm, I have to try that. I didnt think the cable that came with it was THAT cheap looking.
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post #583 of 2239 Old 07-20-2008, 05:57 AM
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Quote:
Originally Posted by 300ohm View Post

I didnt think the cable that came with it was THAT cheap looking.

The supplied cable is fine if you will not be using the analog pass-through feature. You'll see the difference mainly on the higher UHF channels.(Look how thin the center conductor is compared to RG-6)
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post #584 of 2239 Old 07-20-2008, 11:12 AM
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Look how thin the center conductor is compared to RG-6

Hmm, thats not really a fair comparison because that pin is part of the gold plated plug assembly, not the cable. Printed on my supplied cable, it reads >>> Solutions >>> High Definition Video Cable >>>, and thats all. So I really dont know if its RG6 or RG59, but it makes it sound like its RG6.
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post #585 of 2239 Old 07-20-2008, 02:28 PM
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Quote:
Originally Posted by 300ohm View Post

Hmm, thats not really a fair comparison because that pin is part of the gold plated plug assembly, not the cable. Printed on my supplied cable, it reads >>> Solutions >>> High Definition Video Cable >>>, and thats all. So I really dont know if its RG6 or RG59, but it makes it sound like its RG6.

The "pin" is usually the actual center conductor of the cable. The connector (plug assembly) only connects electrically with the shielding and the center conductor extends out through the connector.
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post #586 of 2239 Old 07-20-2008, 06:32 PM
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Quote:
Originally Posted by DigaDo View Post

In the dark the Zenith's LED resembles the light appearing behind Gort's visor just before someone or something gets zapped. "Klaatu Barada Nikto!"

I have this unit in my bedroom. It's certainly creepy, especially in the middle of the night when I see the strange red beacon looking over everything.
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post #587 of 2239 Old 07-20-2008, 07:34 PM
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Originally Posted by Glados View Post

I have this unit in my bedroom. It's certainly creepy, especially in the middle of the night when I see the strange red beacon looking over everything.

The red beacon means that Gort is in standby mode. When the beacon is blue you will know that Gort is ready to act. You must respond saying "Gort, Klaatu Barada Nikto!"

Have a good night.

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post #588 of 2239 Old 07-20-2008, 11:54 PM
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So far my DTT901 (April build) is checking out good.

BTW in Hawthorne, CA the CC store now has May builds and all of the older 900/901s are gone! Likewise all of the older Insignia boxes at BestBuy across the street have been replaced by June builds of the new passthrough model. I wonder if LG recalled them....

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post #589 of 2239 Old 07-21-2008, 01:51 PM
 
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I already tested the Zenith DTT900 versus Dish DTVpal. Although both received 4 stations, the DTVpal had lots of macroblocking on the weak channels so there was effectively only 1 watchable station. 4 stations versus only 1.

Here are my results with Zenith DTT900 versus the Channel Master CM7000:

- Rabbit Ears = 4 stations versus 5 stations.

- CM4228 antenna = 8 stations versus 13 stations.

- Amplified settop antenna = Same number of stations but the Zenith experienced breakups, whereas the CM7000 was a solid 99-100 the whole time. No freezing or macroblocking.

IMHO the CM7000 is the better box, with the ability to display stations as low as 10 on the strength bar. At 10 the picture sometimes "smears" like a water-color painting, but at 20 it looks near-perfect. I was able to watch an entire episode of Cold Case from Philadelphia 50 miles away and it hovered between 20-40 on the strength bar. It appears the CM7000 has better error-correction.
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post #590 of 2239 Old 07-21-2008, 02:46 PM
 
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Quote:
Originally Posted by Digital Rules View Post

The supplied cable is fine if you will not be using the analog pass-through feature. You'll see the difference mainly on the higher UHF channels.(Look how thin the center conductor is compared to RG-6)

I'm not sure if the thickness or thinness of the wire makes any difference. Remember that a coaxial cable is a *waveguide*, and the signal is NOT carried on the actual wire. Instead the signal bounces back-and-forth between the center wire and the metal shield. Somewhat akin to this:

______________ <----- shield
/\\/\\/\\/\\/\\/\\/\\/\\/
---------------- <---- center wire
______________ <----- shield


In a waveguide what matters is the thickness of the *whole* cable, where a larger cable has less loss. The cable used for TV studios are often 1/2 an inch across so that they can travel ultra-long distances with minimal loss.
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post #591 of 2239 Old 07-21-2008, 08:31 PM
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Quote:
Originally Posted by rmcneil321 View Post

The "pin" is usually the actual center conductor of the cable. The connector (plug assembly) only connects electrically with the shielding and the center conductor extends out through the connector.

Hmmm, so you think theyre gold plating the entire center wire. I dont think so, heh. Plus the center pin is machined slightly where it attaches to the plastic. It has to be soldered/connected on the inside to the copper cable, which is worse than having it go straight thru.
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post #592 of 2239 Old 07-22-2008, 06:58 AM
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Quote:
Originally Posted by rrrrrroger View Post


Here are my results with Zenith DTT900 versus the Channel Master CM7000:

- Rabbit Ears = 4 stations versus 5 stations.

- CM4228 antenna = 8 stations versus 13 stations.

- Amplified settop antenna = Same number of stations but the Zenith experienced breakups, whereas the CM7000 was a solid 99-100 the whole time. No freezing or macroblocking.

Does your Zenith DTT900 have a Sanyo tuner or an LG one?
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post #593 of 2239 Old 07-22-2008, 07:24 AM
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The advertisement state "universal" remote control but all it will do is turn the TV on and off - no other functions such as volume or channel change when set top box is "off". Disappointed that the remote is not what is advertised.
The insignia has the same remote
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post #594 of 2239 Old 07-22-2008, 08:33 AM
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Quote:
Originally Posted by rrrrrroger View Post

I'm not sure if the thickness or thinness of the wire makes any difference. Remember that a coaxial cable is a *waveguide*, and the signal is NOT carried on the actual wire. Instead the signal bounces back-and-forth between the center wire and the metal shield. Somewhat akin to this:

______________ <----- shield
/\\/\\/\\/\\/\\/\\/\\/\\/
---------------- <---- center wire
______________ <----- shield


In a waveguide what matters is the thickness of the *whole* cable, where a larger cable has less loss. The cable used for TV studios are often 1/2 an inch across so that they can travel ultra-long distances with minimal loss.

This is not correct. The signal is carried on the conductors. The impedance of a coaxial cable is the ratio of the AC voltage to current flowing in it. It is determined by the ratio of the inner conductor thickness to the inner diameter of the shield and the type of insulator used to separate them. To reduce the loss in a cable, keeping the insulating material the same, the inner conductor must get bigger which forces the outer conductor to get larger as well to keep the impedance at 75 ohms. The inner conductor can be made larger without making the outer bigger up to a point by changing the insulating material. The ideal insulator is none at all in other words air but then a way must be found to keep the inner conductor centered in the outer. For large none flexible coaxial cable this is done with teflon pins spaced every so often down the cable.

Rory
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post #595 of 2239 Old 07-22-2008, 09:02 AM
 
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Quote:
Originally Posted by Rory Boyce View Post

This is not correct. The signal is carried on the conductors.

FALSE. The cable is a waveguide and the signal bounces between the outer conductor (shield) and the inner conductor (wire). The signal is NEVER carried "on" the wire. If such a feat was tried, using a piece of plain wire, the signal would die after only a few feet.

As for the thickness of the inner conductor, that does make sense. Thicker == less loss.
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The impedance of a coaxial cable is the ratio of the AC voltage to current flowing in it.

You could have just said R = Vrms/Irms. Simplify, not obfuscate.
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post #596 of 2239 Old 07-22-2008, 09:38 AM
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Originally Posted by Albireo View Post

Just picked up 3 DTT901's at the local CC in Mechanicsburg, Pennsylvania.

I sifted through the 3 layers of boxes and found the latest units based on manufacture month and serial number, and they happen to be consecutive serials:

806SHxx100617, 806SHxx100618, 806SHxx100619 (all June 2008)

All units are DTT901 (CUSALZK) 85E02561 models.

I finally decided to wave the cable company bye-bye and will be installing a combo VHF/UHF Winegard antenna soon. I've been paying $20 a month for Broadcast Basic Cable that is only providing channels I can receive over the air anyway. Just hoping that my subdivision homeowner's association doesn't bulk at the TV antenna... They can go pound sand as far as I'm concerned.

Your homeowners association CANNOT prevent you from installing an outdoor antenna. It's the LAW - Telecommunications Act 1996. Unless your homeowners association will provide you the signal you require - for FREE. Otherwise - go ahead and install the antenna up to 12 feet above your roof line if that is what it takes to achieve the necessary signal. Same thing applies if you are a renter.
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post #597 of 2239 Old 07-22-2008, 09:51 AM
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Quote:
Originally Posted by rrrrrroger View Post

FALSE. The cable is a waveguide and the signal bounces between the outer conductor (shield) and the inner conductor (wire). The signal is NEVER carried "on" the wire. If such a feat was tried, using a piece of plain wire, the signal would die after only a few feet.

Then the Paper Clip Antenna has a substantial relationship with the RF connector into which it's inserted; but if the broadcast frequency required an antenna of (say) several feet in length a Paper Clip (type) Antenna of the appropriate length would (then) lose its ability to deliver a satisfactory signal?

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post #598 of 2239 Old 07-22-2008, 11:40 AM
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[quote=rrrrrroger;14342767]FALSE. The cable is a waveguide and the signal bounces between the outer conductor (shield) and the inner conductor (wire). The signal is NEVER carried "on" the wire. If such a feat was tried, using a piece of plain wire, the signal would die after only a few feet. /QUOTE]

I assume that you have a degree in electrical engineering like I do?

How do you explain the fact that you connect to the WIRE to get the signal into or out of the cable? How do you explain the opertion of stripline or microstrip. How do you explain the operation of 300 balanced transmiission line which has less loss than coax and no outer conductor at all.

Rory
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post #599 of 2239 Old 07-22-2008, 12:19 PM
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[quote=Rory Boyce;14344061]
Quote:
Originally Posted by rrrrrroger View Post

FALSE. The cable is a waveguide and the signal bounces between the outer conductor (shield) and the inner conductor (wire). The signal is NEVER carried "on" the wire. If such a feat was tried, using a piece of plain wire, the signal would die after only a few feet. /QUOTE]

I assume that you have a degree in electrical engineering like I do?

How do you explain the fact that you connect to the WIRE to get the signal into or out of the cable? How do you explain the opertion of stripline or microstrip. How do you explain the operation of 300 balanced transmiission line which has less loss than coax and no outer conductor at all.


I agree with Rory.

At high frequencies the signal travels on the surface of the conductor, this is know as "skin effect". The higher the frequencis, the more the effect. In a coax cable the outer shielding provides the return ground path and also shields the inner conductor from outside interference. There is a relationship between the spacing of the inner & outer conductors and the dielectric properties of the insulating material which affects the capacitance of the cable which in turn affects how much signal is lost. This capacitance starts to short out the signal, and this loss increases as frequency increases. RG6 coax has less loss than RG59. For short lengths you will probably never notice a difference between the two.

A wave guide is used at even higher frequencies and the signal does bounce back & forth inside the guide.
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post #600 of 2239 Old 07-22-2008, 02:06 PM
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Quote:
Originally Posted by Rory Boyce View Post

For short lengths you will probably never notice a difference between the two.

I agree; but on a "very weak" analog channel 68; I can see a difference.
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