Every spring at this time I like to summarize the standard viewpoint held by KDX Worldround Radio regarding Part 15 AM radio transmitters.
Most persons contemplating to build a low power AM station begin to wonder which transmitter will give the most range. But two other questions should come first:
1.) What is the available budget?
2.) How much engineering experience do you have?
The trick to getting the most on a small budget is to build your own transmitter from sstran.com, the AMT3000 or AMT5000.
But without the skill to solder and build a kit part by part, a larger budget is required to obtain a ready-built transmitter from several suppliers in this category. In essence, one is paying for his own lack of skill; that is, paying someone else for having built and marketed a complete package.
For those having the choice of going either way the question of range depends of such factors as RF output efficiency of the transmitter and antenna design with good radial ground system.
The AMT5000 operates in the Class E mode achieving 98% output efficiency (manual p.26), well above the norm of other transmitter designs which more typically achieve perhaps 50% output efficiency.
Arguments abound regarding output efficiencies of the costly prebuilt transmitters, but their output efficiencies are only claimed but undisclosed, resulting thus far in mere sports-like "challenges" regarding range.
Even the least costly AMT3000 from sstran.com, designed for in-home use, can be upgraded to a serious contender in the range category by following the free instructions for improving the output/antenna system.
Here at KDX Worldround Radio we operate an AMT3000 with our own self-built loading coil/antenna, and an AMT5000 according to the manual instructions, and our only concern regarding range of either transmitter is to pull back so as not to trigger an "inspection" for excess field strength.
What's in your wallet?