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This new unit appears to be functionally similar to the older government-regulated CECBs. It includes SD outputs (RF and composite) plus HD outputs (component video and HDMI outputs). I've been wondering if the tuner's RF performance is comparable (or better than) with the long-departed CM-7001 CECB, and if it would offer a performance upgrade (in terms of tuner reception and selectivity) for our remaining SD CRT televisions.

http://www.channelmaster.com/Digital_to_Analog_Converter_Box_p/cm-7003.htm

Theoretically, over the past eight years there would have been improvements in ATSC tuner performance, but is this just another el-cheapo Chinese-made tuner unit like the iView, Viewtv, Mediasonic and its ilk? There doesn't appear to be any recording functionality here, just a glorified HD-capable box which can function either in SD (with old sets) or in HD (with newer sets). I'd like feedback before shelling out money on this, as my aging Zenith/Insignia and Zinwell CECBs still function well. :)
 

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I found one of the images they show for the 7003 interesting. It might be a way to combine the signals from two antennas aimed in different directions by creating a mini-headend.
 

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Looks like this new Channel Master 7003 converter box could be a similar Chinese clone of the iView or Mediasonic boxes, but not really sure. But nice to have the HDMI connection, although the overall design is probably not the same as the original Channel Master CECB box, which had a very good tuner.

However there is also a new Channel Master 7002 Digital TV Hub box which allows for a Roku type box to also be connected, and it appears to have a nice program guide. It was on sale for $59 but the price has gone back to $89 again.
 

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I think tylerSC is right. The CM-7003 user manual is identical to the one for my HomeWorX, except for photos & drawings (e.g., of the remote) and the fact that they (belatedly) removed the two pages about scheduling recordings. The screen shots are also virtually identical to HomeWorX screens.

I don't know if they actually removed recording functionality from the firmware. (I'm not aware of anyone who has one of these yet.) But whether it can record or not, CM doesn't seem to want folks to know that recording is/was possible. I guess they worry it would compete with their DVR+.

Unless CM has made major improvements to the firmware, which I doubt, I'd say the HomeWorX is the better deal.

BTW, the CM-7002 is interesting, although it looks overpriced to me. The '02 appears to combine an ATSC tuner and HDMI switch into a single box. No recording, but it does seem to have a slick UI.
 

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I bought a CM 7003 to see what it would do. My primary interest is for a tuner to be used with a TV when you have two antennas aimed in different directions. The main antenna would be connected to the TV antenna input and the second antenna would be connected to the 7003. The output of the 7003 would be connected to the TV HDMI or component input for HD reception.

The 7003 is very small in comparison to earlier converter boxes; almost as small as the Cox mini box which is needed because the QAM cable channels are now mostly encrypted. The connectors on the back are very close together and the box is so light weight that it is necessry to tape the coax down to keep it from pulling the box off the table.

The coax jumper that comes with the box is a disgrace. The center conductor is smaller than the 18 gauge used for RG6 and is bent off center.



The illustrations in the manual are hard to read. The first impression is that this is a cheap piece of equipment that might not perform well and might not last very long.

In spite of this first impression, the 7003 seems to perform well with OTA signals and its tuner is just as sensitive as the tuner in my Sony KDL32R400A.

I removed the cover to take a look inside:

 

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I did some screen shots to see what the illustrations in the manual should look like.













 

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It is possible to add a channel after scan. I verified this by a double rescan with the antenna disconnected and then entered the real RF channel number in Manual Search.



If you press the INFO button on the remote this is what you see. The signal bar is not valid in the INFO bar.



If you press it a second time right away you will see Signal Quality:



The remote control is a little flaky. The aim and distance are critical and it often takes more than one press to activate a function. It reminds me of the remote for the Apex DT502. I wonder if teaching a learning remote would do any better.
 

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I've been wondering if the tuner's RF performance is comparable (or better than) with the long-departed CM-7001 CECB, and if it would offer a performance upgrade (in terms of tuner reception and selectivity) for our remaining SD CRT televisions.
I was also wondering about the tuner. My standard test for tuner sensitivity is to feed two tuners from a splitter and insert an attenuator before the splitter to see which tuner drops out last as I increase the attenuation, making it the winner. I didn't have my regular test equipment at this location, but I did have a 32" Sony that I had calibrated for signal strength with my signal level meter (SLM).

Sony KDL32R400A
GE 34792 Attic Antenna indoors at ground level
Antennas Direct ATT-1 20 dB Variable Attenuator
1 FAM Attenuator 10dB

ANT > ATT-1 > 10 dB fixed > splitter > tuners






The ATT-1 knob has 3-3/4 turns, so I put a mark on the knob with an ultra fine point Sharpie to count the turns. Clockwise rotation increases the signal; minimum attenuation at full clockwise rotation. I started there, and rotated the knob counterclockwise to increase the attenuation for the test.

I used the WTKR CBS, RF 40, virtual 3.1 signal for the test. It wasn't as stable as an LOS signal that I usually use because of trees, but it was what was available for the test.

These are the readings:

Code:
spacer
Tuner Sensitivity Test
Sony KDL32R400A vs Channel Master 7003

ATT-1       Sony        7003    Signal
Turns  Signal SNR dB  Quality  dBm  dBmV

  0      38     26       70    -70  -21
  1      34     24       63    -74  -25
  2      30     21       53    -78  -29
2.25     28     19       49    -80  -31
2.50     24     15       40    -84  -35
2.75             dropout
spacer
Dropout was at about -85 dBm, where you would expect it to be.

Thermal Noise Floor -106 dBm + 15 dB SNR = -91 dBm
and then adding tuner Noise Figure:
-91 dBm + 6 dB Tuner NF = -85 dBm



 

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I tried the CM-7003 and two TVs on Cox cable.

Sony 32" TV
2 analog, 5 digital
Channel
16 NTSC, 133.250 MHz, Color Bars
60 NTSC, 439.250 MHz, Color Bars
68.7431 QAM256, 489.000 MHz, Program Unavailable notice
68.7432 same
68.7433 same
76.5 QAM256, 537.000 MHz, Color Bars
85.7350 QAM256, 591.000 MHz, Program Unavailable notice

Samsung 19" TV
2 analog, 5 digital
Channel
16 Color Bars
60 Color Bars
68-431 Program Unavailable notice
68-432 same
68-433 same
76-5 Color Bars
85-350 Program Unavailable notice

CM-7003
5 digital
68.7431 Program Unavailable notice, Quality 96%
68.7432 same
68.7433 same
76.5 Color Bars
85.7350 Program Unavailable notice, Quality 96%

The 7003 does not tune analog NTSC, but will pass it through in standby. It will decode unencrypted (clear) QAM. This would make it suitable for users with an analog TV that is connected to cable that has analog and clear QAM signals.

It is also suitable for areas that still broadcast analog and digital OTA signals to users with an analog TV.

It is not suitable for users with a "TV'" without a tuner which is now called a display (AKA monitor) for cable systems with analog and clear QAM.

And of course, it is suitable for digital OTA signals with any TV, monitor, or projector, which is what I had in mind.
 

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Rabbit73, thanks for the review. This is the first review of this box I've seen!

Your screen shots are very similar to corresponding Homeworx and iView screen shots. I compared the CM-7003 screens with an old iView firmware version (20031213 aV13), and saw only a few differences:


  1. On the Program screen, iView has a Sort option, but it doesn't work. (Also, iView's second option is labeled EPG instead of Guide.)
  2. On the Picture screen, iView firmware has a TV format screen that can be set to NTSC or PAL. Pretty useless in N. America unless you have a PAL TV you bought overseas.
  3. On the Channel Search screen, iView firmware has an intriguing Antenna Power option that will send 5 volts to the RF input to power an amp. Obviously that only works with the few preamps that use a 5-volt power injector.
  4. Also on the Channel Search screen, iView has a Modulation setting that can be set to Ch. 3, Ch. 4, or Loop Through. If set to Loop Through, the RF signal is passed through when the box is on, not in standby (opposite the CM-7003).
  5. On the Time menu, iView lacks the Power On/Off option (but HomeWorx has it). This can be used to schedule a time for the box to turn itself on and/or off. Newer iView firmware versions have a 12/24 Time Format setting in place of the Power On/Off option.
  6. The Option, System, and USB menus are identical on both. I note with interest the CM-7003 does have a PVR Configuration menu, implying the recording feature does exist on this box (despite CM's efforts to conceal it)!
If it wouldn't be too much trouble, could you go to the System menu, select Information, and post what is displayed? Also could you post a screen shot of the guide?
 

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JHBrandt:

Thank you for the interesting comparisons between the boxes. I will work on your request and post the results.
 

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I have both the CM 7003 and the HomeWork PV150, the boxes look completely different, but the software appears to be exactly the same, with subtle changes.

The Menu looks exactly the same and EPG works on my PV 150 but gives no information for some channels...



DSC00012.JPG
 

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I have both the CM 7003 and the HomeWork PV150, the boxes look completely different, but the software appears to be exactly the same, with subtle changes.

The Menu looks exactly the same and EPG works on my PV 150 but gives no information for some channels...

View attachment 1825233
Thanks! Does the Book function work? Will it schedule a recording, then record the show if an HDD is attached?
Vice versa on the previous screenshots, sorry.

The grey cast is the CM 7003,

The blue cast is the PV-150

There's no edit function in this forum?
Edit: My HW-150PVR (V2.1 firmware) is definitely gray. I think you had it right the first time, because the screen with the blue cast shows colored buttons a la the CM-7003 remote. BTW, that's a big difference in signal (82% vs. 45%) for what appears to be the same channel on virtually identical boxes :confused:

You should see an "Edit" button at the bottom of each of your own posts.
 

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Rabbit, can you elaborate on this?

How would you set it up?

Thanks, Bob
That diagram shows a tuner and a QAM modulator for each channel to combine them into one coax system. Even if the modulators could do more than one channel, it would be expensive.



In your case with two antennas, each aimed in a different direction, the most cost effective solution would be to have two coax runs to each TV. For the TVs that have a tuner, connect antenna 1 to the antenna input of the TV and connect antenna 2 to the input of the 7003, with its output going to the aux input of the TV.

For your "TV" which doesn't have a tuner and is now called a display (AKA monitor), you would need two external tuners with their outputs going to the inputs of the display. If the tuners were both the same brand, there would be a problem with the remote control.

For reference, Bob did try to combine both antennas into one coax, but lost some channels.

There is a video that shows how to avoid the remote control problem with two CM DVRs. I have no idea if it will work with two 7003s.
 

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System Info
Thanks. The "7802" in the HW Version is the SoC. The newer HomeWorXes and iViews use the same chip. However, I'm not sure what that "148MM" is. I wonder if the CM-7003 uses a different demod chip? Edit: Nope - the pic you posted earlier of the circuit board definitely says 1237, same demod chip as the HomeWorX and iView.

Thanks! That shows the CM-7003 guide has the same Book function as the HomeWorX and iView. This is to schedule a program to be recorded. Someone needs to try this and see if it works.
For your "TV" which doesn't have a tuner and is now called a display (AKA monitor), you would need two external tuners with their outputs going to the inputs of the display. If the tuners were both the same brand, there would be a problem with the remote control.
Luckily he has a CM-7003 and an HW-150PVR, and they use different remotes. So as long as his monitor has two HDMI inputs, two component inputs, or one of each, he should be good.

There is a video that shows how to avoid the remote control problem with two CM DVRs. I have no idea if it will work with two 7003s.
Worth a try, but probably won't work (there's a pic of the CM-7003 remote at CM's web site, and it's different from the DVR+ remote).
 

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Someone needs to try this and see if it works.
I tried recording, and it worked for me after a little trial and error. I ordered some 8 GB USB drives, but they sent me 32 GB drives. I inserted one in the front and did a format and recorded a few minutes, but I couldn't figure out how to playback because the instructions were too skimpy for me. I finally realized I had to go into USB in the menu to playback.
 
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