I would like to be able to control my antenna rotator the same way I control my satellite receiver.

Does anybody have any idea on where to start? I'm looking over at lirc.org to see if anybody already has a config file. It's not looking too good.

I have an XG91 Yagi antenna (almost 100" long) with a pre-amplifier. I live in a fringe area, nearest tower is 15 miles & it's LP PBS. I get that unamplified w/ an indoor antenna. Everything else is blocked by hills or is 40+ miles away.

So I have multiple markets that my antenna can receive signals from.

I have 2 ch 3's, 2 ch' 44's (both different networks), etc.

Any idea how to program schedules direct & my listing data such that if a show on ch 3 at 300 degrees has a show I want recorded it will turn the antenna accordingly? And when that program is done to turn the antenna again for ch 32 at 41 degrees for another program?

I understand that I'll only be able to record in 1 ota direction at a time. I have FTA satellite and I do have 1 antenna pointed at my preferred location, but I still like to have other programming.

ATSC makes for great quality recording.

Please let me know if anybody has any ideas or know's where I should start looking.

Thanks,

~ryan

I found the manual on-line for my channel master rotator. Basically, it will respond to codes issued to it as a pioneer device (HH1 (cable box) or HH2).

What I need to do is pre-program the box for the azimuth of each channel.

I can pre-program upto 68 channels.

I can make ch3 @ 300 degrees programmed ch 1 and ch3 @ 141 degrees programmed ch 2, and etc. I have to do this via the factory (or universal remote).

Once my channels are programmed, I then have to edit my channel lists so that when ch1 is selected from the guide, it sends a 01 signal to the irblaster & then it will move the antenna to the correct azimuth.

I'll make a chron job to manually sync the rotator (full CCW turn) once weekly or something like that. It's a matter of sending a 00 down (have to figure out what the down button corresponds to, but that's easy according to the LIRC documentation.

It looks like I'm all set for this. I'll let you know how it goes once I get a few hours to mount the new mast & motor & run the cable for the antenna.

Yet another great thing about mythTV, being able to control antenna rotators ... next project is to get it to control a custom made tilter .... that way I can compensate for the curvature of the earth at 60+ miles for super long distance channels.

~ryan


next time i won't ask my questions outloud before doing research .... but then again ... if I didn't ask my question .... my answer may never have made it here for others ....

ryan,

I don't mind you thinking 'out-loud,' as I'm getting to the same point as you... I need to find a way to get the rotor to 'tune in' stations on the fly.

I'm in a REALLY fringe area, and without a rotor, I can only get ONE ATSC station. Using a rotor will let me pull in five more. I was thinking that the rotor control would have to be combined with the channel changing scripts...seems like you're on the same track.

I asked over on avsforum about using a tilter, too, but was told that it's not worth the investment based on my location. The XG91 should catch whatever is out there. A good amp on the mast is a must. I don't have the XG yet, but I'm hoping to upgrade this summer.

I currently have the old RadioShack rotor, and was looking online for the IR controlled base. There's one out there, and it's probably the same as yours.

larry

yeah ... i've had a few babble the tilter is not worth it. I might just take a rotator, mount it horizontally & attach an arm to it & to my antenna and use 180 degrees of it for up & down ... I have tall hills in my way of the signal .... i'll manually tilt the antenna to see if it makes a difference using online antenna tilters.

the channelmaster IR controller will control the radioshack rotator. http://www.pctinternational.com/channel ... 521_37.pdf is the manual for the rotator

treat the channel changing scripts like you're changing the channel on a satellite receiver ..... but then again that's usually on s-video input :-/

I'll have to give it more thought on how / what to do

i won't be able to do anything for a few days / week or so .... we just got another foot of snow so the roof isn't exactly ideal. We had a warm spell & I was too busy to get up there & do stuff.

keep me posted

More out loud thinking...

My ATSC tuner is the Air2PC card, that's IN the computer. I was poking around the setup screens, and saw the external channel script location IF you're using an S-Video input, but nothing for the internal DVB card. I'm wondering HOW I'll be able to change the intenal tuner card AND external antenna rotor at the same time?

Thinking about it a bit, I may have to move the antenna FIRST, then tune the card, otherwise Myth will display the message about not receiving a lock on the station.

I ordered the IR Rotor controller from Solid Signal. I'll have to figure it out when it shows up.

To follow up this conversation and document my progress...

I have the CM ir rotor controller and have an irblaster setup to send signals to the box.

After poking around in the Myth databases, I attempted to hack an 'external channel change command' into the DVB-T card setup. The table was cardinput. It's initially set to NULL, but I just changed that and added my script, using the full path name (/usr/local/bin/chgATSCchnl.sh). Just to make sure, I changed the permissions on it to allow world execution (chmod 777).

After linking that and creating a dummy script to at least tell me that it was run shows that it's NOT being called from within Myth.

It appears that the Myth code needs to be patched to allow DVB-T cards to send external channel change commands. It seems that DVB cards can issue Diseqc, but that's only useful dish type controls. With the current setup, us OTA folks need multiple tuner cards and antennas. Ugh!

I'd like to try and hack this in...somewhere.

Edited 3/9/08 for more details

More followup...

After searching the net and browsing the Myth code, it appears that the external tune script is only allowed for S-Video and Composite input cards, and it's expected that the external tuning script does ALL of the tuning work.

This code is in the /mythtv/libs/channel.cpp and channelbase.cpp files.

The relevant code is SetChannelByString function in channel.cpp.

The above code ONLY controls NTSC tuning. The code for DVB tuning is located in dvbchannel.cpp

I've done some hacking to the NTSC tuning portion, and I believe that it will work. Just some code cleanup.

The ATSC portion is buried around code for channel numbers, like '12-1,', and I'm trying to have the rotor controled via channel frequency, NOT the channel number, since some ATSC towers are not at the same location as the NTSC tower for the same channel. This may help out others, too.

IF I can get this to work, the code will need a LOT of polish, and some linkages for the setup GUI to expose the new functionality.

Hi Larry,

Sorry about the extended delay. I've been swamped with service calls lately.

Thanks for making some progress with this project. I'm still thinking it over, but I'll look at it some more in the coming weeks when work slows down. The snow is still here for a couple more weeks, so I can't get outside to install the new antenna's & rotator.

Looks like I'll have 2x 91Xg's. 1 on the rotator, and 1 pointed at a static location. I also have a VHF antenna for 1 channel that will remain VHF after the conversion & 1 smaller directional UHF pointed to Canada for the Wife & Kid's.

Now I need to figure out how to have schedules direct work with it all in different media markets.

Gotta love having some low power transmitters that will remain analog after 2009. So I'll have to split one of my 91xg's so it can feed an analog tuner & the digital tuner when it's pointed at a mountain that will have some analog signals and the digital signals.

~ryan

Slightly off-topic: is there a list somewhere of which channels are staying UHF and which are moving back to VHF after the conversion? I've got just a UHF antenna on my roof and need to know whether I need to get a VHF/UHF antenna instead.

Also, thanks to you two for doing this, it'd be great to have a channel rotation script (sadly I have zero scripting ability so I can't help other than maybe testing).

Hi,

I have been using this method:

in Google, search " <your state> digital channels " (no quotes) which will render a link that looks like:

http://en.wikipedia.org/wiki/List_of_te ... ations_in_<your-state>
It has most of the grusesome details.

Mike

Crap. I'm going to need a VHF/UHF antenna. <sigh> I was hoping to get away with my UHF only.

http://en.wikipedia.org/wiki/List_of_television_stations_in_California

_________________
Mike
My Hardware Profile

Follow up...

I did some hacking in the code, and I can get the calls to an external change script to work...

BUT.... (always a but)

It seems that the tuners (atsc and ntsc) are 'tuned' to a station immediately after the backend code is started. After that, the atsc section is only called again IF it needs to change the channel.

That makes initial tuning on the atsc card a problem. I was hoping that the code was more OO, and there was a central 'tuning' section regardless of tuner type, but it's not that way.

Other issues I've determined:

The external tuner script (that would turn the rotor) needs to delay the backend so that the station will be properly tuned. There's a brief delay in the code, but that is too short (30 seconds). My rotor needs about 70 seconds to do a full turn of the anntenna. This external script would have to track where the antenna is, where it needs to go, and how much time it'll take to get there.

It's getting complicated. Ugh.

One last point: try http://www.tvfool.com The site can map your reception as of now and AFTER the NTSC shutdown. Lots of good info there![/url]

Hi Larry,

Just checking in to see if you've made some headway.

~ryan

No, not much progress here.

I'm waiting for some time off work so I can install my new 91xg with an old rotor. That controller works well with the CM IR controller. It works the RS rotor that I have installed, but It can't do a complete 360 turn since the timing is slower.

I haven't touched the code in over a month. Having other issues that are consuming most of my free time.