Channel Master converter box, out of the box

[wa2ise]

Bought another Channel Master CM7000. Fired it fresh out of the box, without an antenna, and took a look to see what stations were loaded into its memory. It showed 3 stations, a channel 6-1, and two KPBS channels. Looked up KPBS at the FCC web site, and it's a station in San Diego, channel 15 analog, 30 digital. Looking at tvfool.com, looks like there's a Mexican DTV station on 6.1, XETV near San Diego. Looks like Channel Master tests these boxes in San Diego. Probably after they get them off the ship, and before loading them onto trucks to send them to stores.


Fry's has them on sale Feb 14th for a penny less than $50 instead of the usual penny less than $70.

[Ed in Tx]

So is the CM a good one? I have a coupon I need to use, and a Fry's about 5 miles down the road...

Have you compared to the Zenith box by chance?

[wa2ise]

Originally Posted by Ed in Tx

So is the CM a good one? I have a coupon I need to use, and a Fry's about 5 miles down the road...

Have you compared to the Zenith box by chance?

It's pretty good, it gets a weak Seattle NBC channel 5 better than my Zenith box. And it has S video, so if you have a set with S video inputs, you can have really nice clear no NTSC cross luma-cross chroma artifacts. And if you collect old B&W sets you can grab just the luma (B&W) for it, without the checkerboard pattern chroma subcarrier. And the CM uses a prefilter on the composite signal before it hits the TV modulator, so the signal has proper group delay characteristics just like real NTSC stations had.

[Ed in Tx]

Well darn.. got to lookin', if it had pass-thru I would go get one tonight. I need that feature so I can tune in my satellite receiver on the TV that converter box will go on. (A '94 model 27" Sony with S-video input). I feed the satellite to other rooms in the house through the ant coax cable with a combiner, modulated with a MTS stereo modulator on Ch 3. Looks like a DTV coupon-eligible box with S-video and pass-thru may be hard to come by.

[Phil Nelson]

Heck, wish I had seen this post sooner, would have driven 15 miles to the nearest Fry's (in Bellevue) and picked one up. I have heard good things about the Channel Master. Already have a Zenith which works pretty well.

Are you located near Seattle? I thought I was the only collector in this desolate wasteland where no vintage TVs are to be found

Phil Nelson

[ChrisW6ATV]

My new CM7000 had that same list of stations when I set it up last weekend. I agree that this box is a good receiver, and the s-video output is a nice improvement on a monitor that accepts it. It seems to tune channels about as fast as the Zenith DTT900, and both are quite a bit faster than boxes from a few years ago. They are nearly fast enough to allow good old fashioned click-click-click-click mindless channel surfing.

[Duane]

Originally Posted by wa2ise

Bought another Channel Master CM7000. Fired it fresh out of the box, without an antenna, and took a look to see what stations were loaded into its memory. It showed 3 stations, a channel 6-1, and two KPBS channels. Looked up KPBS at the FCC web site, and it's a station in San Diego, channel 15 analog, 30 digital. Looking at tvfool.com, looks like there's a Mexican DTV station on 6.1, XETV near San Diego. Looks like Channel Master tests these boxes in San Diego. Probably after they get them off the ship, and before loading them onto trucks to send them to stores.


Fry's has them on sale Feb 14th for a penny less than $50 instead of the usual penny less than $70.

Yep..those are San Diego stations.

XETV actually broadcasts from Tijuana.

[wa2ise]

With the S-video output, I could see some NTSC luma-chroma separation artifacts on a program on some Spanish language channel. A game show that looked like a knock-off of the "Price is Right". The show must have been supplied as an NTSC videotape, and they had to separate the luma and the chroma before it got digitized and encoded into the MPEG ATSC DTV signal.

If all a DTV SD channel has is a composite NTSC video source, then it will never look as good than if the programming was available with separate luma and chroma, or YUV or YCrCb.

Most DTV stations use programming with clean luma and chroma (or more normally YUV or YCrCb). Live HDTV will always be clean, even when downconverted to S-video by the CM7000. When the S-video luma and chroma signals are merged together to produce composite NTSC, that's when cross luma/chroma starts getting yucky.

[Jeffhs]

With the DTV transition now set for June 12, I'm wondering how folks like myself, who do not have digital cable (I have expanded basic from Time Warner), will be able to see the digital stations when the analog ones go off the air. I fully understand that folks who do have any kind of cable service (including bare-bones basic, which is local channels only) will not notice any difference when the switch is made. What I am wondering is how the ATSC digital signals will be converted so that standard NTSC televisions can receive them, without a cable box. I spoke recently over the phone with a TW customer service representative, who told me that for subscribers with any level of cable service, the conversion will be handled by a box-shaped device on the roof. I live in a 12-unit apartment building; almost all the tenants, myself included, have cable (I think there may be one person here who still uses rabbit ears).

I don't know, however, how many tenants have flat panels with built-in ATSC tuners or are using cable boxes ahead of the sets; most of us have cable because OTA television reception in this area is terrible.

My question: How can one ATSC->NTSC converter be used with (for example) a dozen televisions, without signal-strength problems at either end of the line? I'm thinking the signal may be split among the sets by means of one or more signal splitters, of the type used with antennas serving several TVs, with an in-line amplifier to compensate for signal losses in the cable.


BTW (for wa2ise): When did you move from New Jersey to Seattle? I recently looked up your amateur radio callsign on Buckmaster's callsign server and found that your license still has your Oradell, NJ address. If you're in Seattle permanently, I'd change the address on the license ASAP. As you know, the FCC has very strict rules as to licensees keeping their addresses current. After the one-year mail forwarding order expires, the FCC may not be able to find you if you are 3,000 miles from the address they have in their database. This can cause real problems the next time you renew your license, or if the FCC tries to send you any type of correspondence. In fact, failing to keep your current address on file will in itself be a violation, and could cause the Commission to deny your next renewal.

[andy]

000

[3Guncolor]

Andy,
You are 100% correct. Where I work we are already using the 8VSB over the air signal if we don't have a studio feed from the station. And you are correct we don't use $50 coverters either. There is no 8VSB signal on the cable plant it's all QAM for the digital versions of the station. We have three versions of most stations SD analog, SD digital and HD digital. In other words we are no longer using any over the air analog signals from the television stations.

[wa2ise]

Originally Posted by Jeffhs

I spoke recently over the phone with a TW customer service representative, who told me that for subscribers with any level of cable service, the conversion will be handled by a box-shaped device on the roof. I live in a 12-unit apartment building; almost all the tenants, myself included, have cable (I think there may be one person here who still uses rabbit ears).


My question: How can one ATSC->NTSC converter be used with (for example) a dozen televisions, without signal-strength problems at either end of the line? I'm thinking the signal may be split among the sets by means of one or more signal splitters, of the type used with antennas serving several TVs, with an in-line amplifier to compensate for signal losses in the cable.

That box on the roof is essentially a miniaturized cable head end, several ATSC to NTSC converters inside, and each with a modulator to a (probably) VHF TV channel. Likely no pass-thru.

Originally posted by 3Guncolor:
You are 100% correct. Where I work we are already using the 8VSB over the air signal if we don't have a studio feed from the station. And you are correct we don't use $50 coverters either. There is no 8VSB signal on the cable plant it's all QAM for the digital versions of the station. We have three versions of most stations SD analog, SD digital and HD digital. In other words we are no longer using any over the air analog signals from the television stations.

You could probably just demodulate the 8VSB signal down to the MPEG bitstream, and then remodulate that into QAM onto a cable channel. So far as I know, cable uses the same MPEG 2 codecs as ATSC. No need to decode to just reencode, if they intend to keep it as HDTV. Else they do decode, downscale, then reencode if it's to be SD DTV or just go to analog NTSC.

Originally Posted by Jeffhs

BTW (for wa2ise): When did you move from New Jersey to Seattle? I recently looked up your amateur radio callsign on Buckmaster's callsign server and found that your license still has your Oradell, NJ address. If you're in Seattle permanently, I'd change the address on the license ASAP. As you know, the FCC has very strict rules as to licensees keeping their addresses current. After the one-year mail forwarding order expires, the FCC may not be able to find you if you are 3,000 miles from the address they have in their database. This can cause real problems the next time you renew your license, or if the FCC tries to send you any type of correspondence. In fact, failing to keep your current address on file will in itself be a violation, and could cause the Commission to deny your next renewal.

Not to worry, I'm only on a contract job in Seattle, and will be returning to Oradell, NJ soon. Just in an extended stay hotel in Seattle, and still paying taxes out of NJ. So the FCC and the IRS should be happy.