The AM Transmitter Challenge has arrived

Mr. Fry:

I've noticed this error in your posts for several years, but I'll mention it for the first time now: Engineering graduates may be excused for not knowing the difference between the words "affect" and "effect" because that is not exactly their bailiwick, but for those who have managed to earn a BA degree, it's simply not excusable.

Ermi Roos said:

... Engineering graduates may be excused for not knowing the difference between the words "affect" and "effect" because that is not exactly their bailiwick, but for those who have managed to earn a BA degree, it's simply not excusable.

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No technical rebuttals (let alone support) from you, we see. As for your attempted lesson about the use of the words affect and effect...

In my post #60 I wrote (underlines added), "There would be NO relative difference in the affect of ground conductivity on the fields radiated by, and (accurately) measured for any of the systems of this 'Challenge.' "

The word "affect" in that sentence is a verb, and was used correctly there. The electrical characteristics of the earth act on, or produce a change in the e-m fields traveling along, and just below the surface of the earth.

"Effect" would be the change (a noun) in the radiated e-m wave resulting from the action of its contact with the earth.

Is it really excusable for engineering graduates, or even high school graduates not to know this difference?

By the way, I learned the correct use of "affect" and "effect" in junior high school, if not beforehand.

Now, can we get back to technical matters?

I'll have to defer to you in grammatical matters, since your degree is a BA. Technical matters are something else, however.

Ermi Roos said:

... If the AMT-5000 were actually operating class E, it would definitely have had technical superiority over the Rangemaster. But the manufacturer said a scope "should" not be required for tuning. ...

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Would anyone care to reply to the comments below?

For Class E input power held constant at 100 mW, do peak output power and peak efficiency occur at the same setting (tuning)?

Would the mis-tuning suggested by Mr Roos when using the instructions provided for the AMT5000 account for the 3.3 dB reduction in radiated fields noted for the AMT5000 relative to the Rangemaster, in the "Challenge?" If so, this means that the AMT5000 setup radiated only about 47% of the power radiated by the Rangemaster setup -- but other factors may have contributed to the difference measured.

Class E operation was first clearly explained not by the inventors, Nathan and Alan Sokal, but by Frederick H. Raab, in "Idealized Operation of the Class E Tuned Power Amplifier" in IEEE Transactions On Circuits and Systems Vol. CAS-24, No. 12, December 1977, and the related paper, "Effects of Circuit Variations on the Class E Tuned Power Amplifier" IEEE Journal of Solid-State Circuits, Vol. SC-13, No.2, April 1978. The patent by the Sokals was issued November 11, 1975, but it is very confusing to read, and so the Raab papers should be considered to be the seminal papers on the subject. Fry might obtain copies of these papers if he thinks that his self-study has prepared him to comprehend them.

There are two tuning capacitors in the canonical circuit that have to be adjusted correctly for Class E operation to exist. One is C1 from collector to emitter, and the other is C0 in the output series-tuned circuit. These two adjustments interact with each other. Both have to be adjusted correctly for there to be Class E operation. The AMT-5000 tuning instructions only deal with tuning the output series-tuned circuit. No, Class E operation does not correspond to peak power output.

To be told that you can adjust a class E circuit with an unknown output resistance (which is the unknown ground resistance using the AMT-5000) without using a scope, is to be sent on a fool's errand. Without viewing the collector (or drain) pulse, you have no idea what is going on. The "fool," will not be aware that his operation is sub-optimal because the transmitter will seem to be working fine even with large misadjustment, unless he has the instruments needed for evaluating its performance.

There appears to be an implicit assumption that anyone who criticizes the Challenge is upset with the results. That IS an assumption, and it is wrong. I have no issues other than to see unbiased test results.

The results are what they are, within the parameters of the testing. However, no matter how much it is protested, the Challenge does NOT end up with a transmitter winner, i.e. the transmitter that generates the highest field strength. It is really testing the transmitter PLUS the antenna system, as the antennas are not all equal. Now, the Challenge was an interesting test, but I wouldn't use the results to choose the transmitter that I would want to use if I was starting all over again in Part 15 radio. As an example, even an AMT5000 that performed as well as in the test, but with a well-constructed external base loaded antenna would probably wipe the socks off everything else.

Further, if you were going to test everything as it was delivered by the manufacturer, then you wouldn't have included the AMT5000 in it, as you would be testing raw electronic components. So I wouldn't stick too closely to your argument that you were just using the transmitters as supplied.

I also understand that using identical antennas might have changed the transmitters that you were testing, but so what? That's the only scientific way to compare the transmitters alone (which IS the title of the test and the magazine article).

The reason that so many are keying into the AMT5000 as the 'oddball' in the Challenge is that the results don't make a lot of sense. It should have performed better, based on real, reported results. And in science, when something like that happens, you don't just staunchly defend your experiment or test, stating that IT couldn't have been done any better - you attempt to find out why you got the results you did (it could be the test that is at fault). There are plenty of potential reasons other than the antenna used why that could have happened that are not the fault of the transmitter. From the build quality of the kit, to the apparent issues with the documentation in tuning - all could have negatively affected the results for that transmitter.

Putting the antenna issue aside for the moment, one simple way to verify that particular showing of the AMT5000 would have been to test another example, although if the problem was tuning, then it just would have been repeated. The better way would have been to reach out to others who have used this transmitter and perhaps even gotten one or more involved. Ideally the manufacturer would have been involved, but I do understand that they declined to do so. The point is, you don't blame, but you endeavor to obtain the CORRECT results.

You want to see if the same results are obtained - that's just good science and engineering. And you would have gone a long way to silencing the critics.

I personally would like to see a showdown between the Rangemaster, the Grain and the AMT5000 (suitably verified, of course,preferably by the manufacturer, and armed with indisputable tuning information). All using identical antennas. If you were going to use a whip you could also throw in a Talking House with a whip as well. It would be even better to then test all with an external antenna, similar to the ATU/whip combination of the Talking House (maybe even that particular combination, but keeping the feed coax very short to eliminate the possibility of it radiating) - however, it's been a while since I've used the Rangemaster, and I've never used the Grain, so I'm not sure if they can accommodate external antennas. If not, then it might not be possible.

Then you would truly have a transmitter 'winner'.

The AM Transmitter Challenge has exposed the fallacy of the tuning method of the AMT-5000, which I had anticipated and posted about long before the Challenge was even proposed. Actually, it was the luck of the draw, because the circuit is capable of operating Class E, but you have to be lucky to tune it correctly with an unknown ground resistance without a scope.

I don't know how the manufacturer has cultivated the enthusiastic following that he has, with even Fry, to whom he has been very nasty, trying to defend him.

Why have I written so many posts in a row? It is because this website punishes long-winded posters by at first just requiring them to log in again, but finally crashing the entire post that took a long time to type. So, it is better to post a little bit at a time than to lose all of one's work by typing too much per post. A positive comment on this site is that the automatic spell-check, which I noticed just recently, is really nice.

@Ermi: I usually just compose my posts offline in Notepad or a similar program, then log-in to post. That should eliminate the time-out issue.

@Geets: I don't assume that all who criticize the Challenge are upset. I view it that many simply don't understand the basis of how the testing was conducted.

geets said:

There appears to be an implicit assumption that anyone who criticizes the Challenge is upset with The results are what they are, within the parameters of the testing. However, no matter how much it is protested, the Challenge does NOT end up with a transmitter winner, i.e. the transmitter that generates the highest field strength. It is really testing the transmitter PLUS the antenna system, as the antennas are not all equal. Now, the Challenge was an interesting test, but I wouldn't use the results to choose the transmitter that I would want to use if I was starting all over again in Part 15 radio. As an example, even an AMT5000 that performed as well as in the test, but with a well-constructed external base loaded antenna would probably wipe the socks off everything else.

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As stated before, all transmitters were tested in the configuration as supplied or described by their respective manufacturers in their product documentation. If a transmitter used a factory-supplied antenna or a whip antenna with or without an external tuning apparatus that was what was used. If the antenna supplied by the manufacturer was a simple wire lead then that was what was used. There is nothing mentioned in the product documentation for the AMT5000 for a "well-constructed external base loaded antenna," so that falls outside of the scope of the testing. It was tested with the wire lead as supplied by the manufacturer. Just to be complete, while there are switch settings available to accommodate an external coil it isn't available from the vendor as an included or optional accessory nor are any standard values or instructions supplied to arrive at a coil to provide any specific level of performance.

All transmitters were aligned and operated in the manner outline by the accompanying product documentation. It wasn't my job nor was it within the scope of the challenge to correct any mistakes made any manufacturer relating to their documentation or alignment procedure. The documented alignment and operating instructions were followed as a end user would do.

The AMT5000 would have benefited from a more detailed alignment procedure. I'm sure it would have performed better than observed if there had been more detailed information regarding jumpers S14 and S15, but in following the supplied documentation there were no other suggested setting for these jumpers other than the defaults indicated in Section 20 of the product manual. Of course, with only one sample there are variables that could have also affected performance such as tolerances in components,assembly variances, etc. This also could be said for any of of the test specimen since there were only one sample tested for each device.

The vendor for the AMT5000 transmitter kit supplies the raw components, a printed circuit board and instructions for assembling the transmitter. The only difference between this and a manufactured transmitter is that it the end user assembles the device themselves - they're still raw components assembled to a circuit board to provide some useful circuitry. As far as using an external whip antenna on the AMT5000, other than bypassing the internal tuning circuity to accommodate an coil of undetermined value there are no other accommodations mentioned within the product documentation so you would be operating in near-identical conditions of the wire lead antenna.

FYI: If you review the challenge text you may note that both short and long coaxial cables were tested with the i.AM.Radio's external tuner and no appreciable difference in signal was indicated so the factory-supplied coax cable was used.

RadioCityBill, I believe that most who are criticizing the Challenge do indeed understand the parameters of the test. Within those parameters, a fine job was done by all.

I just don't think that they are expressing their concerns all that well. If someone was starting up a Part 15 station and wanted the quickest and easiest way, you could use the results. And within the caveats described, the Rangemaster could indeed be considered the 'winner'. But that's it.

If I wanted to achieve the greatest possible range with my station, i.e., the OPTIMUM results, not worrying about who is to blame re documentation, and not worrying about what is delivered with the transmitters, then the Challenge is certainly open to question. Particularly since you are admitting that there may have been issues with the tuning of the AMT5000. And different antennas were used with different transmitters.

I do think that your analogy re the kit and your comment on testing multiple examples is open to debate. It is more likely you are going to generate errors assembling a kit than just using a factory assembled unit. Yes, there can be issues even with factor assembled ones (I know I've had widely differing results with different examples of the Talking House), but if you obtain a transmitter from a dealer or a manufacturer, say, they're presumably going to check it out before releasing it (particularly for something like the Challenge). And there are quality controls during the manufacturing process. It may have been that the AMT5000 used was assembled correctly, but then, it may not have been. One more variable.

geets said:

If I wanted to achieve the greatest possible range with my station, i.e., the OPTIMUM results, not worrying about who is to blame re documentation, and not worrying about what is delivered with the transmitters, then the Challenge is certainly open to question. Particularly since you are admitting that there may have been issues with the tuning of the AMT5000. And different antennas were used with different transmitters.

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From what I can gather, Geets, it sounds like you're more familiar with this type of transmitters where you would seek performance beyond a plug 'n' play result. The Challenge was presented for those who had contacted me via my web site seeking a transmitter comparison where they lack a certain familiarity with this type of equipment, perhaps even being more correctly defined as an "appliance operator." As such, they are not going to seek out other antennas like you've suggested several times - they are going to operate the unit in their unmodified, stock configuration.

These same people also going to take the product documentation as gospel and set up the equipment in accordance to that very same documentation. If the documentation presents shortcomings which prevents the end user from realizing optimal performance of the equipment that is beyond the control of the end user and as such those limitations reared their head during the Challenge.

geets said:

I do think that your analogy re the kit and your comment on testing multiple examples is open to debate. It is more likely you are going to generate errors assembling a kit than just using a factory assembled unit. Yes, there can be issues even with factor assembled ones (I know I've had widely differing results with different examples of the Talking House), but if you obtain a transmitter from a dealer or a manufacturer, say, they're presumably going to check it out before releasing it (particularly for something like the Challenge). And there are quality controls during the manufacturing process. It may have been that the AMT5000 used was assembled correctly, but then, it may not have been. One more variable.

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In almost 40 years of broadcast engineering I've seen a number of commercial broadcast transmitters, those assumed to have been fully tested at the factory prior to their delivery to the site, have problems grossly apparent upon installation. I do recall a 50KW station that had two brand new transmitters that were factory modified for a greater power level. One of them blew up upon power-up during its installation, which was totally unexpected. I wasn't involved with this other installation but I also recall hearing about a brand new transmitter being installed at a 6KW FM station where the transmitter similarly "soiled the linen" when fired up. So, factory assembly verses kit assembly doesn't really mean the factory is infallible to error.

The vendor of the AMT5000 was requested to provide either a short-term or long term evaluation unit for the challenge, but declined. With such I acquired a suitable substitute by other means. I have no reason to doubt the AMT5000 which was loaned to me wasn't assembled in a manner typical of a end user and the performance therefore followed what was expected.

RadioCityBill, it's my opinion that you're taking the parameter 'as delivered' a little too strictly. If there were holes in the documentation (I don't know what you had, how old it was, etc.), then why not just contact the manufacturer and get the correct information - the fact that you had to do so could be reported in the results of the Challenge? To just go ahead when you have pretty much admitted you didn't understand everything in the tuning process and complete the testing 'as is' invalidates the results for that particular transmitter. I'm sure that the manufacturer would have supported the product - there is a huge difference between not providing a free transmitter for a test, and product support (for all I know, he's been burned badly in the past with giving out free transmitters for 'testing' purposes). In fact, Phil has explained the tuning process for the AMT5000 on other Part 15 sites. And if the technical support did not do anything for the performance, then it would have indeed been fair to continuing the testing in the manner that you did. But I guess we can agree to disagree on that one.

Your argument re the build quality of the AMT5000 is fallacious. How could you know if there were errors or not in the construction if you only tested one example? And you obtained results that were somewhat surprising, at least compared to ancedotal information that is available elsewhere? There could have been errors with other transmitters tested as well, as you pointed out. My own experience with both Talking Houses and the ProCaster (of which I've owned over 3 of each) is that I've gotten wildly different results with different examples (the earlier ProCasters in particular were prone to breakdown of the tuning capacitor, with little evidence that that was occurring until it went completely - I had at least 2 fail in that fashion). That could have thrown ALL the tests out of whack.

So that I can be clear, within the parameters of the Challenge, I'm really not arguing with you at all (except for the AMT5000 results, for which, as I've indicated earlier, I believe that the parameters were interpreted too strictly). But I AM saying that within real world Part 15 broadcasting, unless you're a newbie, you're going to investigate other antennas. You're also going to use a modulated carrier and audio processing, which may affect field strength(may not either) but will certainly affect range. Some transmitters can use other antennas, some can't. Some can do assymetric modulation (or distort modulation, as the Grain site says - obviously they can't do it), some can't. Some just sound better than others. All these factors can play into a more experienced Part 15 broadcasters choice, governed, of course, by THEIR goals. In future tests, if there are any, it would be nice to consider some of those factors as well.

I know that I intend, in the near future, to finally get to testing my AMT5000 (mounted in a weatherproof box with a whip antenna), and I'm going to do it side by side with the Rangemaster, using identical grounds, identical audio chains, and identical programming. Unfortunately, I don't have a FIM, so I'll just do it by 'seat of the pants' driving around and listening.

geets said:

RadioCityBill, it's my opinion that you're taking the parameter 'as delivered' a little too strictly. If there were holes in the documentation (I don't know what you had, how old it was, etc.), then why not just contact the manufacturer and get the correct information - the fact that you had to do so could be reported in the results of the Challenge? To just go ahead when you have pretty much admitted you didn't understand everything in the tuning process and complete the testing 'as is' invalidates the results for that particular transmitter. I'm sure that the manufacturer would have supported the product - there is a huge difference between not providing a free transmitter for a test, and product support (for all I know, he's been burned badly in the past with giving out free transmitters for 'testing' purposes). In fact, Phil has explained the tuning process for the AMT5000 on other Part 15 sites. And if the technical support did not do anything for the performance, then it would have indeed been fair to continuing the testing in the manner that you did. But I guess we can agree to disagree on that one.

Your argument re the build quality of the AMT5000 is fallacious. How could you know if there were errors or not in the construction if you only tested one example? And you obtained results that were somewhat surprising, at least compared to ancedotal information that is available elsewhere? There could have been errors with other transmitters tested as well, as you pointed out. My own experience with both Talking Houses and the ProCaster (of which I've owned over 3 of each) is that I've gotten wildly different results with different examples (the earlier ProCasters in particular were prone to breakdown of the tuning capacitor, with little evidence that that was occurring until it went completely - I had at least 2 fail in that fashion). That could have thrown ALL the tests out of whack.

So that I can be clear, within the parameters of the Challenge, I'm really not arguing with you at all (except for the AMT5000 results, for which, as I've indicated earlier, I believe that the parameters were interpreted too strictly). But I AM saying that within real world Part 15 broadcasting, unless you're a newbie, you're going to investigate other antennas. You're also going to use a modulated carrier and audio processing, which may affect field strength(may not either) but will certainly affect range. Some transmitters can use other antennas, some can't. Some can do assymetric modulation (or distort modulation, as the Grain site says - obviously they can't do it), some can't. Some just sound better than others. All these factors can play into a more experienced Part 15 broadcasters choice, governed, of course, by THEIR goals. In future tests, if there are any, it would be nice to consider some of those factors as well.

I know that I intend, in the near future, to finally get to testing my AMT5000 (mounted in a weatherproof box with a whip antenna), and I'm going to do it side by side with the Rangemaster, using identical grounds, identical audio chains, and identical programming. Unfortunately, I don't have a FIM, so I'll just do it by 'seat of the pants' driving around and listening.

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What ever you do, don't post the results.

geets said:

RadioCityBill, it's my opinion that you're taking the parameter 'as delivered' a little too strictly. If there were holes in the documentation (I don't know what you had, how old it was, etc.), then why not just contact the manufacturer and get the correct information - the fact that you had to do so could be reported in the results of the Challenge?

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Hmm, a vendor ignores various communications from email to snail mail and registered snail mail and you suggest contacting them? I was more than reasonable in my attempts to reach out to him and it's quite obvious unless you're one of his cheerleaders you'd likely be ignored as well.

geets said:

To just go ahead when you have pretty much admitted you didn't understand everything in the tuning process and complete the testing 'as is' invalidates the results for that particular transmitter. I'm sure that the manufacturer would have supported the product - there is a huge difference between not providing a free transmitter for a test, and product support (for all I know, he's been burned badly in the past with giving out free transmitters for 'testing' purposes). In fact, Phil has explained the tuning process for the AMT5000 on other Part 15 sites. And if the technical support did not do anything for the performance, then it would have indeed been fair to continuing the testing in the manner that you did. But I guess we can agree to disagree on that one.

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I never stated anything about misunderstanding the tuning process for his transmitter. The adherence to following the factory supplied instructions for each tested unit was equally applied across the board to each manufacturer's product. It was beyond the scope of the challenge to re-engineer the documentation or perform additional tuning steps which weren't covered in the product's accompanying documentation.

If Phil did explain his tuning process on various web sites why was it conspicuously absent from the factory supplied documentation? If he could expound upon it to people who may or may not own the product why not include it so the people who actually spent their hard earned money on the product could benefit from it?

geets said:

Your argument re the build quality of the AMT5000 is fallacious. How could you know if there were errors or not in the construction if you only tested one example? And you obtained results that were somewhat surprising, at least compared to ancedotal information that is available elsewhere? There could have been errors with other transmitters tested as well, as you pointed out. My own experience with both Talking Houses and the ProCaster (of which I've owned over 3 of each) is that I've gotten wildly different results with different examples (the earlier ProCasters in particular were prone to breakdown of the tuning capacitor, with little evidence that that was occurring until it went completely - I had at least 2 fail in that fashion). That could have thrown ALL the tests out of whack.

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The Challenge made appropriate mention that with a single sample quantity of each unit it may prove difficult to show manufacturer variations, etc., which might allow for variances of a particular product's performance. Measuring of the unmodulated field intensity of each transmitter was intentional to not have any carrier shift compound the issue. Each transmitter was measured on its merits of taking the 100 milliwatt input power and evaluating how efficiently it would apply said signal to the factory intended and/or supplied antenna. With a single sample of the AMT5000 I had to trust that the assembler followed the factory supplied instructions and the demonstrated performance was typical for the device. Similarly, I had to do this with every other sample that was tested.

geets said:

So that I can be clear, within the parameters of the Challenge, I'm really not arguing with you at all (except for the AMT5000 results, for which, as I've indicated earlier, I believe that the parameters were interpreted too strictly). But I AM saying that within real world Part 15 broadcasting, unless you're a newbie, you're going to investigate other antennas.

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Which is the intended primary audience of the challenge. Anyone with more advance experience might experiment with non-standard configurations which was beyond the scope of the Challenge.

geets said:

You're also going to use a modulated carrier and audio processing, which may affect field strength(may not either) but will certainly affect range. Some transmitters can use other antennas, some can't. Some can do assymetric modulation (or distort modulation, as the Grain site says - obviously they can't do it), some can't. Some just sound better than others. All these factors can play into a more experienced Part 15 broadcasters choice, governed, of course, by THEIR goals.

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As I mentioned above, unmodulated carriers were used strictly to eliminate any carrier shift from compounding field intensity results.

geets said:

In future tests, if there are any, it would be nice to consider some of those factors as well.

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Discrete product reviews are intended to include modulation and measured frequency response. In fact, due to the graciousness of those who loaned two of the transmitters they will likely be the first to be evaluated in this manner.

geets said:

I know that I intend, in the near future, to finally get to testing my AMT5000 (mounted in a weatherproof box with a whip antenna), and I'm going to do it side by side with the Rangemaster, using identical grounds, identical audio chains, and identical programming. Unfortunately, I don't have a FIM, so I'll just do it by 'seat of the pants' driving around and listening.

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An excellent "seat of the pants" measurement could be made if you have access to a Grundig G8 or similar radio that uses the same chipset as it does (which I believe there are several other brands that do). A vendor of traveler's information service (TIS) systems sells the G8, which they sell as a compliance appliance for their TIS/HAR systems, along with their proprietary documentation that allows the radio's S-meter to approximate a rough value of field intensity. While I won't disclose their proprietary documentation I do plan on performing an in-field calibration of a couple of G8's against my FIM and publicly posting those results to allow other radio enthusiasts to use these radios within the realm of Part 15 signal levels.

@Bill, what I find amusing is that the person who lent you the SSTran did not post any complaints about the methodology of the test. Also amusing is that Rich's comment that he would not make a decision about purchasing a Part 15 transmitter based on the test results. That being said, what would make Rich happy enough to make a decision if and when he decides to purchase a Part 15 transmitter?

pascoradio said:

... Also amusing is that Rich's comment that he would not make a decision about purchasing a Part 15 transmitter based on the test results. ...

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That is not a statement I posted either here or elsewhere.

Please check your source for the correct author.

In Error Again!

rfry said:

That is not a statement I posted either here or elsewhere.

Please check your source for the correct author.

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Let the record show that once again (2 times this week) that I, Pascoradio was in error. It was not Rich but ArtisanRadio that made that statement. Rich simply quoted Artisan and I mistook it as a statement from Rick. My apologies Mr. Fry.

pascoradio said:

... Pascoradio was in error. It was not Rich but ArtisanRadio that made that statement. Rich simply quoted Artisan and I mistook it as a statement from Rick. ...

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Thanks for the clarification, John.

I'll be happy to answer your question, pascoradio. I wouldn't choose a transmitter based solely on the results of the Challenge because, in my opinion, there were too many issues in the testing. I still stand by my statement that anyone, even a newbie, would attempt to do the appropriate research and find out how to properly tune a transmitter if they didn't fully understand the documentation - and the difficulty with the AMT5000 documentation in the Challenge has been admitted here. According to them, it isn't the tester's fault that they didn't know what they were doing - it was the manufacturer. The only explanation I have for this attitude is that perhaps the fact that the manufacturer didn't respond to the Challenge was taken as a personal affront. It's certainly mentioned often enough.

So how would I choose that transmitter? The Challenge is ONE data point, but only one. There are many people actually doing Part 15 broadcasting on a regular basis who have used all of these transmitters (I myself have used many, as well as others) and reported their particular findings (that's why I have some doubts about the Challenge in the case of the AMT5000 - it doesn't match what others have said). I'd then choose one or more, and test them to MY requirements. If there's one thing I've learned in over 8 years of flea powered broadcasting is that you have to try things and see how something works for YOU.

I don't understand why any comments or discussion surrounding the Challenge are met with such resistance. Despite my own particular comments, I feel they did a good job. They obtained one set of data. There are some questions about that data. Further testing might resolve those questions. But not if it's raise-the-drawbridge every time someone doesn't just fall down before the Challenge and sing its praises.