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  #1  
Old 07-25-2016, 05:27 PM
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Hawkwind Hawkwind is offline
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DTV Box

I need a good box for the Tampa Bay area. and one that would be good for DX'ing. I have a great outdoor antenna, a 7up with a channel 10 yagi...
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Old 07-25-2016, 06:38 PM
matt99 matt99 is offline
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Maybe a Zenith DTT901. But DTV dxing will be difficult, since the ATSC signal is well known to be "all or nothing" on reception. I don't have a DTT901 but they seem to be well regarded for reception and reliability. About 5 years ago, I did find one on the ground in the parking lot of a park. For whatever reason, I decided to smash it with a rock and dump it in the creek in a nearby wooded area. At least I can vouch for the solid build quality
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Old 07-25-2016, 10:33 PM
centralradio centralradio is offline
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DTV DXing LOL.I cant even get one bloody channel here and the TV tower is only 10 to 15 miles away.I still have my 2 $40 buck coupon freebies here somewhere which I got from Walmart when they did the switch.I think they are Magnavox or RCA,I cant remember at the moment.Also I have 2 Sharper Image 7 inch sets which receive some channels if I'm on top of the mountain in town here.
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Old 07-26-2016, 12:04 AM
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Electronic M Electronic M is offline
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The Zenith 900 series and the insignia and LG badged versions there of are real good. (can't believe you smashed a free one!) Out in Town of Barnes Wi (about as far from large populations as I've been) I was able to get 6-8 watchable DTV carriers and their sub channels with just an old 60's UHF bowtie on a Zenith. My Kworld ATSC tuner dongle on my laptop was only able to get 2 carriers.
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Old 08-11-2016, 11:33 AM
dieseljeep dieseljeep is offline
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The Zenith 900 series and the insignia and LG badged versions there of are real good. (can't believe you smashed a free one!) Out in Town of Barnes Wi (about as far from large populations as I've been) I was able to get 6-8 watchable DTV carriers and their sub channels with just an old 60's UHF bowtie on a Zenith. My Kworld ATSC tuner dongle on my laptop was only able to get 2 carriers.
On a side note, T-W cable in my area, totally discontinued all forms of analog reception. The last of the channels that were still analog, now have a screen that shows a message that states, "You need one of these", to get a picture. It shows a picture of the digital converter, that they furnish.
My 20" RCA, that everyone seems to hate, still gets the broadcast-type DTV channels from the cable. Same with jail sets, but they have to be re-scanned, as the ota, vs the cable frequencies are different.
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Old 08-11-2016, 03:49 PM
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It is the same here. There probably ain't much time left for the 'get a box' casts either.
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  #7  
Old 08-12-2016, 05:57 AM
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Robert Grant Robert Grant is offline
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Originally Posted by Hawkwind View Post
I need a good box for the Tampa Bay area. and one that would be good for DX'ing. I have a great outdoor antenna, a 7up with a channel 10 yagi...
The LG-designed Zenith and Insignia boxes have a good reputation for reception that does hold up well when comparing them to other DTV converters. DXers really love them because they have the manual tuning mode that allows one to go through the actual RF channels instead of having to do a scan (it will also scan if you prefer).

Note that not all Insignia boxes are of the LG design. Some later ones are not as good.

The Sansonic and Zinwell boxes have worked well for me. The Magnavox boxes, derided for their plastic construction, lack of manual tuning, and dependence on the remote control, actually are decent in sensitivity and multipath tolerance.

Multipath tolerance is a term you may have never heard before. In fact, the smart phone I'm typing this post on didn't even recognize multipath as a word! Yet, it is at the crux of ATSC reception issues.

Multipath occurs when a signal reflects off of a mountain, building, wall, or even a person, and interferes with the desired (usually direct) signal. In analog TV, this resulted in "ghosting", but in DTV, it turns the stream of octal numerals (from which a microprocessor assembles picture and sound) into gibberish - and no content is received at all. The consequence of this is that someone in a wood frame farmhouse may get reliable, perfect reception 50 miles away from the transmitter, whilst someone living downtown, a mile from the transmitter, gets nothing.

TV DXers have received ATSC DTV signals from distances in excess of 1400 miles, and one DXer recently logged his 700th DTV station.

There is a club forum where TV DXers have compared DTV converter boxes and TV sets and posted their observations.

Last edited by Robert Grant; 08-12-2016 at 06:33 AM.
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Old 08-12-2016, 11:33 AM
dieseljeep dieseljeep is offline
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DTV DXing LOL.I cant even get one bloody channel here and the TV tower is only 10 to 15 miles away.I still have my 2 $40 buck coupon freebies here somewhere which I got from Walmart when they did the switch.I think they are Magnavox or RCA,I cant remember at the moment.Also I have 2 Sharper Image 7 inch sets which receive some channels if I'm on top of the mountain in town here.
The Walmart units were Magnavoxes, made by Funai. Most of the units that are around are Magnavox, as they were only $10.00 with the coupon. The first ones came through with a poorly designed remote control, where the channel up-down buttons were in the upper right corner. Older users couldn't use them, as the buttons were too tiny.
The Mags were cheaper, as the video cable wasn't included, just the RF.
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Old 08-12-2016, 01:08 PM
centralradio centralradio is offline
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Originally Posted by dieseljeep View Post
The Walmart units were Magnavoxes, made by Funai. Most of the units that are around are Magnavox, as they were only $10.00 with the coupon. The first ones came through with a poorly designed remote control, where the channel up-down buttons were in the upper right corner. Older users couldn't use them, as the buttons were too tiny.
The Mags were cheaper, as the video cable wasn't included, just the RF.

Thanks.Yes .Thats what they were Maggie's .I do agree.The remote is a POS poor design.Good grief .Its a Funai.Wonder why they suck on reception here.
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  #10  
Old 08-13-2016, 12:51 PM
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Robert Grant Robert Grant is offline
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Thanks.Yes .Thats what they were Maggie's .I do agree.The remote is a POS poor design.Good grief .Its a Funai.Wonder why they suck on reception here.
Well, what are you using as an antenna, where is it placed (e.g., on the roof, in the attic, on top of your TV), and where are you.

There are websites (TV fool, for example) where you can enter your location, and it will show the direction and signal strength of TV stations in your area.

However, just because the signal is strong does not itself assure good reception. DTV favors outdoor antennas (actually designed under the presumption that a directional antenna 10m (33') off the ground would be in use).

To succeed with an indoor antenna, you almost need to have the indoor antenna behind a window that faces the transmitter sites. You may get away with going through walls if your exterior is wood or vinyl, but brick or stucco (because it has a metal wire mesh inside) will cause trouble, unless you can use a window facing the transmitters or put the antenna in the attic.

Last edited by Robert Grant; 08-13-2016 at 01:34 PM.
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Old 09-26-2016, 07:34 PM
centralradio centralradio is offline
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Originally Posted by Robert Grant View Post
Well, what are you using as an antenna, where is it placed (e.g., on the roof, in the attic, on top of your TV), and where are you.

There are websites (TV fool, for example) where you can enter your location, and it will show the direction and signal strength of TV stations in your area.

However, just because the signal is strong does not itself assure good reception. DTV favors outdoor antennas (actually designed under the presumption that a directional antenna 10m (33') off the ground would be in use).

To succeed with an indoor antenna, you almost need to have the indoor antenna behind a window that faces the transmitter sites. You may get away with going through walls if your exterior is wood or vinyl, but brick or stucco (because it has a metal wire mesh inside) will cause trouble, unless you can use a window facing the transmitters or put the antenna in the attic.
Thanks Robert. That what I got to do is put an attic antenna up.I would love to put an antenna up in the 90 foot pine here but it wont be safe when it gets hit by lightning .I see that BJs has DTV antennas there but dont know about the quality of them and same goes for the ones at Walmart.I need a backup in case the cable goes out for a long time.
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  #12  
Old 10-14-2016, 02:40 PM
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DavGoodlin DavGoodlin is offline
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I agree the Magnavox-Funai box is only so-so for sniffing out weak signals and some new HD sets are awful, Dynex comes to mind. My experiences with the Channel Master CM-7000 were great for DXing as for the Zenith DTT901, Tivax and Insignia boxes. Also the Digitalstream locks onto weak signals too because it also uses the LG chips, so it is similar. Good as these LG-chipped boxes are, some will crap out on you and flash red LEDs, etc- I have had to repair 2 Digitalstreams and it was just failed electrolytics (bulging tops - 470 mf@ 10v) on the secondary side of the switch-mode power supply. DT boxes will show up dead and minus remotes, as $1 bargains in the bins next to DVD players, etc at thrift stores.

Now the CM operates very differently but it is possibly even more sensitive. One thing you cannot do with the CM is pre-tune it for an RF frequency before moving your antenna around to "find" the channel. But it can be "update" re-scanned and just keeps adding channels onto what you have already received. You then can only punch in the virtual number or what was stored (that is the station name, not the RF frequency, which may have changed since 6/12/2009)



But one thing the CM-7000 did better than any other was to sniff out and STORE the most obscure stations' data, even if not stable or even lock in one day, but try it another day and if you get a steady 20% signal or more, it locks. I recommend just aiming the antenna, then scan. After that scan, fine-tune your antenna for the strongest signal on a received channel and scan again.
Do this each time you rotate the antenna and you will store all the channels

The CM unit has been revised to include a DVR but the basic unit was this.... http://www.channelmaster.com/Digital..._p/cm-7000.htm


The best antenna is another subject. I have tried many, old and new. I am not impressed with most of the ones you see online claiming "150 miles" and so on. Great UHF and VHF antennas were all figured out by the end of the 1970s. T

he best value I have seen yet is a "Gray-Hoverman" I have an example that Antennacraft made for Radio Shack in the 70s. It was cheap and it worked like a much bigger antenna. http://www.diytvantennas.com/sbgh.php it is like a 4-bay bowtie antenna, works as well and is easier to make with #10 or 12 bare, solid copper wire and chicken mesh for a reflector screen.
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Last edited by DavGoodlin; 10-14-2016 at 02:48 PM.
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  #13  
Old 10-14-2016, 02:51 PM
WISCOJIM WISCOJIM is offline
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The CM unit has been revised to include a DVR but the basic unit was this.... http://www.channelmaster.com/Digital..._p/cm-7000.htm
"revised to include a DVR"? How so? What model?

.
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Old 10-14-2016, 04:54 PM
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DavGoodlin DavGoodlin is offline
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"revised to include a DVR"? How so? What model?

.
I'm guessing C-M decided there is no money in a plain old STB, but this is another story http://www.solidsignal.com/pview.asp...(7500TB1)&c=HD
BTW-I have bought several antennas and amps from Solid Signal over the last 10 years.
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Old 10-14-2016, 09:53 PM
WISCOJIM WISCOJIM is offline
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I'm guessing C-M decided there is no money in a plain old STB, but this is another story http://www.solidsignal.com/pview.asp...(7500TB1)&c=HD
BTW-I have bought several antennas and amps from Solid Signal over the last 10 years.
That was never meant to be just a STB, it was a DVR all the way. Not at all a revision of the previous CM STBs. It's an entirely different platform, and the tuner works entirely differently.

(I have both, and several more.)

And BTW, CM does still sell a more pedestrian STB. http://www.channelmaster.com/Digital..._p/cm-7003.htm

.
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