[hasan]

OK...I've played with it enough to come to some conclusions. (I only have UHF stations in my area on HD for the HR20...VHF is another can of worms, that I'm not commenting on in this post)

The internal tuner on my Sammy HL-R5667W is far superior in sensitivity to the HR20. It is also less "finicky" (sensitive to issues other than signal strength).

I have made dozens of measurements that:

1. Vary line length
2. Vary signal level
3. Do or don't include a "real" preamp


The quality of the signal reported by the HR20 (and the ability to display same) is VERY sensitive to things that it should not be. (and that the Sammy handles quite nicely).

Varying the line length produces WIDLY varying strength on the HR20 (it should be noted, that the HR20 is NOT measuring strength, but QUALITY. It is measuring a variant of Bit-Error-Rate (BER)) I see differences on the Sammy as well, but not the wild excursions that the HR20 shows. (with bad effects on the ability to display a picture)

Varying the amount of signal to the HR20 also shows that it has much poorer "dynamic range" than the Sammy. The HR20 drops picture sooner on the low end, and sooner on the high end of signal level (as set by an attenuator).

I have found a set of line lengths and gain distribution that "pleases" my HR20 and I am getting excellent performance from it...but it should NOT be as hard as it was for me...and I know what I'm doing with RF (if I do say so myself )

I can now watch the same number of channels on both the Sammy and the HR20. The picture quality and recordings on the HR20 are SUPERB!

I can't imagine the casual user (who expects to turn on the box and have it work properly for OTA) being all that happy with the OTA performance of the HR20. Once one gets it to work, fine...but getting there...I'm not sure how the non-geekie person is going to get optimum performance from the HR20 OTA.

Don't get me wrong, I'm SUPER GLAD I have OTA in the HR20. I use it CONSTANTLY...but it's not for the "faint of heart"...unless you're just blind dumb lucky.

Lots of work to be done on the OTA side of the HR20, BUT...given that I have it working just fine, I would rather D* work on the stability issues like the Black Screen (which I have never gotten). I wanted OTA really badly. I now have it and it works "fine" (the database for available channels needs to be corrected so we get them all, but that's a small matter for me, as I'm only missing non-major network channels)

Let's hope D* focuses the vast majority of their efforts on the stability issues and delays ALL feature enhancements until such time as the box becomes more bullet proof for those who are having major difficultions. Again, I'm not having them (16 weeks)..but it's very clear a signficant minority of users ARE...and we are ALL one HR20 failure from joining them.

 

[Spanky_Partain]

Good Work hasan...

Any chance you can share some kind of a table showing the preferred lengths?

I was only one of the dumb luck users that got very good signals with three different splits off of the antenna coax.

Spanky

 

[slam]

Just wanted to chime in on OTA.

I have not experimented with line length, etc., and I find OTA pretty much unusable so far. I *will* try a different, better antenna and see if that helps, but that's about all the tweaking I have planned.

I'd be fine with skipping OTA *if* D* had all my locals (Portland market) in HD. They have two of four, for some crazy reason. "In negotiations" they tell me. These broadcasters and the FCC and the media companies, with all their squabbles and rules and greed - it's just nuts. We live in a very anti-consumer time.

Anyone else only getting part of their locals? Any word on when this ridiculous situation will be resolved?

 

[hasan]

Good Work hasan...

Any chance you can share some kind of a table showing the preferred lengths?

I was only one of the dumb luck users that got very good signals with three different splits off of the antenna coax.

Spanky

I'd love to, but it just isn't possible. What you are varying is the overall line length from the antenna to the HR20 (including splitter cables), and since everyone elses's is different, I can't give you the "magic" piece. It really is trial and error, but use short lengths (less than 3'). If you can find some 18" jumpers, use them in combo, that would give you 18/36/54...and make sure to try different lengths on different channels, then select the length that gives you the best "distribution" of channel performance.

I would go to Radio Shack (or whatever) and get at least two, perhaps 3 double female F connectors, so you can make your "adjustable" line length. If I were doing it myself, I'd get some RG-6 and make a variety of lengths starting at 6 inches, 12 inches 18 inches, 24 inches, etc...and use them in combo to produce varying "test lengths". Then, when you find one that does the best job, use it.

This is purely experimental ...it's the only way you can do it at this time.

If I weren't going to make my own, I'd look around my "spares"....you're bound to have a few laying around that vary from 18 inches to 3 feet or more...use them in this same experiment.

I wish I could give you something more concrete, but it's just not possible...and we shouldn't have to do this....but...we do, if we want the best performance for the HR20 at the moment.

(and no, I don't have a multi-path problem, before someone suggests it). This appears to be an impedance problem.

 

[Ikari]

I've also had mixed results with OTA. The signal strengths fluctuate wildly and are inconsistent. I haven't played with it much since I don't really need OTA (I gain PBS HD only). It's more of a geek-curiosity for me.

I'm using a small powered indoor antenna which I realize is not ideal but it is the exact setup that I used with the H20 and it worked great with that box. I'll try varying the line lengths - thanks for the tip.

 

[houskamp]

is this a difference of inches, feet, or yards?

 

[jeffloby]

The HR20 receives every channels that my Sony HDTV tuner does. My former HR10-250 tivo didn't receive every channel. I would say in my opinion it is a very good tuner compared to the Tivo.