Apparently so. I stated nothing about raw gain, or net gain, or any specific type of gain. I just passed along some numbers from multiple third parties, which reportedly came from Channel Master.
Just take a look at any simulated data. There are multiple examples of small variations like that. ...
No "warts"; but it could be that applying the mods "cured the warts".
Here is a chart made by me, based on the data in the table (which was reportedly originated from the manufacturer), showing the 4 CM422x antennas (4221, 4228 and their HD replacements):
The "old" and excellent 4221 and 4228 antennas show smooth gain variation across the usable band, while the newer ones have multiple peaks and valleys? For 4221HD, we are looking at 2.5dB gain difference from Ch.27 to Ch.43, and another good dB down and back up from Ch.43 to Ch.60. This should not happen (unless there is a problem, either with the HD antennas, or with the numbers). BTW, the gain for 4228HD also goes beyond "small variations", and the values shown in the table for 4228HD Beam Width (VHF section) look weird as well; which are more indications that this data should be looked at with caution; not taken for granted.
You should immediately adopt my definition and use it forthwith in all your posts. :thumb: You'll be more accurate. There's nothing in the dictionary about an obligation to publish repeatedly on demand.
I think there is overwhelming evidence that it works, yes. You have solid theory going in behind it. Then you have multiple reports from people on that site that it worked. Then you have rabbit73's hard data. Finally, there is this statement from well regarded simulation expert holl_ands...
It's safe to assume holl_ands did simulations with and without the mods. He had no reason to put his reputation on the line without that simple check. It's just a few parameters to change.
We drifted away from the topic, though. This conversation was about the Sigma6HD antenna. Based on the numbers that are available, I stated that it is somewhat better than the 4221HD. You dismissed the initial comparison I did (using the data obtained by holl_ands' simulation); suggested we should use the higher values shown in the table (reportedly from CM), also bump those values up (by an unknown amount attributed to the mods), and declared: "4221HD wins". My next points were:
- Do the numbers in that table look realistic to you? I showed why I think they do not;
- Do we know how much of an improvement the mods bring? The answer seems to be "not really".
I also like the 4221HD. It is more compact, less expensive, available from more than one source, which are all important advantages. But this thread is about a very unusual application, that involves reception under extreme conditions, where any additional dB can make a difference; therefore all my posts were based on documented performance data (not on my assumptions or personal preference).
I am not trying to beat a dead horse, just trying to make sure I am not misunderstood.