Originally Posted by sggoodri
I've been asked by others to re-post my following story to this thread:
I thought I'd briefly share my [edit: mostly - see bottom] successful experience integrating a Zenith DTT900 ATSC converter box with this DVR so that I can record digital TV off an antenna. Bye bye cable!
I chose the Zenith tuner box because I heard that it could be controlled using IR codes for an LG satellite receiver, which the DMR-EH55 knows how to control via an IR blaster. This worked! I configured the DVR setup for Antenna and DirecTV and connected the Zenith as if it were the satellite reciever, on IN3. I connected my antenna to the DVR and connected the RF antenna passthrough from the output of the DVR into the antenna input of the Zenith tuner.
I autoprogrammed the Zenith to find my local channels and went into the settings to disable auto-off. I stuck the IR blaster below its IR port.
The hardest part was configuring the channel numbering scheme. I found that the only workable scheme to make the DVR automatically change channels on the Zenith was to configure the DVR to always use three digits for the channel, and disable four-digit values. I selected 028 when the setup screen asked how the box wants channel numbers like 28 entered. This causes the zenith to treat the third digit as a subchannel number.
Note that the Panasonic sends the channel number out the IR blaster TWICE when it gets ready to record. This caused problems with the Zenith if I didn't use a numbering scheme that included the subchannel; otherwise, the Zenith would switch to the second subchannel number on the second time. For instance sending '4' would go to 4.1 and sending '4' again would go to 4.2; but 041 always went to 4.1 no matter how many times it is sent to the Zenith [edit -see bottom of post].
I spent a lot of time editing the Panasonic's TVGOS channel listings to show just the channels in my area, and selecting IN3 as the source connection. I then programmed the digital channels as follows:
For 4.1, use channel number 41
For 4.2, use channel number 42
For 17.1, use channel number 171
and so forth.
Since I have a wide screen TV, I set up the CECB to output anamorphic wide screen mode for the 16:9 HD stations. This plays back from the DVR as 16:9 full screen on my TV. It's only 480 lines, but it looks good, better than analog cable and way better than an analog antenna.
Edit/Update: I have been having problems with IR blaster control of the Zenith due to the way my Panasonic DMR-EH55 sends the channel command twice. Sometimes it sends the second command so soon after the first that instead of 171 tuning to 17.1 and then 171 tuning again to17.1, the Zenith sees 171171 and interprets this as 17.11 followed by 7.1 !
It looks like the commands are spaced apart better if the DVR is OFF when the recording is scheduled. Most of my shows have been recorded properly while the DVR was off and I wasn't watching, but when a recording started while I was watching another program the tuner control problem surfaced. I cannot find any way to turn off the double-channel-set behavior in the DVR settings, and none of the other numbering schemes I've tried work either. So, the way a DVR attempts to set the channel number remains a challenge for my own integration with a CECB and could certainly affect other people.
I have verified that the DVR has problems setting the channel when recording a second program immediately after the first due to the double-channel-set problem I described above. I can reliably record one program from any channel, in isolation, when the DVR is off. Multiple programs can be automatically recorded if there is an inactive period behind them, again with the DVR off. It is when the DVR has already tuned to one channel and attempts to change to another to record from it that the problem surfaces.
I wish I could program the DVR to send three digits followed by enter rather than just three digits; this would fix the problem, as would not sending the channel number twice when starting a recording. But I see no way to accomplish either with this model of DVR. Another DVR and another CECB would probably have different interaction characteristics.