The AMT5000 Wintenna setup I used in the FORMAL TESTS is still hooked up exactly the same way, but I made a huge DISCOVERY that went unnoticed during the tests.
The AMT5000 Wintenna setup I used in the FORMAL TESTS is still hooked up exactly the same way, but I made a huge DISCOVERY that went unnoticed during the tests.
All the testing was made west bound because that’s the common path for me to come and go. But today I drove east and, HOLY RF IN HEAVEN, the signal in THAT direction more than doubled ANY wastward signal I’ve ever had with the AMT3000s. In fact that is the direction I was trying to reach by radio so a certain neighbor could listen, but the signal never before went far enough.
Now, at that neighbor’s address, the signal is strong with noise, so it’s a “grade B” signal. Then, the very top of the big hill, traveling south on the cross street there are continuous traces of my signal for several blocks. Definite in and out of the program being sent.
Is it riding the power lines? If so, why didn’t the AMT3000 do the same thing?
be sure you have the rf
be sure you have the rf output set right. the amt5k is very tricky and takes some getting used to. it greatly differs from any other transmitter out there.
Good Advice
You are so right kc8gpd.
I had one big time getting everything to work at first, because I was using an antenna whose Farad range (pF, nF) was out of range of the AMT5000.
But this is not a weakness of the transmitter. Fact is, the transmitter is optimized for the most typical 3-meter antenna situation, which is a perfect idea.
My antenna was very unorthodox and at first presented an obstacle, but even for that there was a solution.
Ultimately, the AMT5000 is exactly what the specs promise… EFFICIENT!
Right now I am building an outdoor test site where further tests can continue.
Please mark my words: the AMT5000 is a huge step in the Part 15 cause.
Equal Conditions Equal Concise Results
Indeed. You cannot expect one unit to have miracle performance over the other when the testing conditions…in this case the power output adjustment on the 5K, is different to the 3K pre set power level.
You MUST make sure that 5K unit is exactly the same in power input as the 3K unit. A 2 to 5 percent tolerance is not too far out of range, but nonetheless throwing a victory party over a unit that clearly can be adjusted way beyond the standard limits and the other cannot, is in my book not any fair test of any degree.
The claim is that the 5K has better efficiency to its little brother 3K. This can only be observed when the test conditions are the same for BOTH units through and through…including power levels.
And do not forget, loading characteristics on that “wintenna”, or any other for that matter, will in fact alter the coupling efficiency as well as power levels due to that loading characteristic.
So testing with a simple wire vs a wintenna or 3 meter stick is no assurance of better efficiency.
Set up the tests so they are identical to each TX, such as the power level setting and antenna being connected.
Then and only then will you even prove to yourself that it is not some odd ball weird effect your celebrating over..but true testing results from true testing conditions.
RFB
from a purely technical
from a purely technical standpoint and a design standpoint all else being equal the amt5k should outperform the amt3k and even the rangemaster by virtue of being able to be modulated 125%, having a larger tuning inductor than the 3k or rangemaster and its class e efficiency. if you can find a way to set it up to full class e to a manteca magnum over a good ground plane there is absolutely no reason why it wont outperform anything presently on the market. again this is from a on paper technical standpoint.
Prospective
Well any properly designed AM transmitter could be modulated out to 125% with the proper processing gear. Rangemaster cannot do this without external help.
But you bring up an interesting point..and one that would make a very good comparison test.
Test the 5K and 3K and Rangemaster with asymmetrical processing
and then without it. Then there will be the “both sides to the story” results.
RFB
The AMT3000 to 5000
The AMT3000 to 5000 comparison just doesn’t excite me; I found that the 3000’s performance was very wanting compared to the Rangemaster (and to the ProCaster, for that matter).
I will be very interested in a comparison, if it’s done, between the 5000 and the Rangemaster, using a 3 meter whip as an antenna. Ideally, the 5000 can be mounted in a weatherproof box at ground level with that whip, so fair testing can be conducted. I was actually disappointed when I found out that the form factor for the 5000 was pretty similar to the 3000; it would have been nice to have the board mounted directly inside a weatherproof box designed specifically for it, and the various holes and antenna mounts already there (like the Rangemaster).
I’ll do the testing myself if I can get hold of a built 5000 – I’m just not all that interested (nor do I have the time) to put the thing together myself.
I’d be very happy if the 5000 significantly outperformed the Rangemaster – it would just set the bar higher for other manufacturers, both in terms of efficiency/range and cost.
it gets mounted in a nema
it gets mounted in a nema enclosure that is exactly like the one used by hamilton.
in this case the horizontal rca jacks and pots are replaced with vertical ones.
all else hooks up just like the hamilton.
only difference is the compressor is onboard and the tune up is a bit more involved.
i own both. i have done rudimentary testing and found the amt5k to be far superior to the hamilton.
i will when able do a side by side with exact same ground / antenna setup for both and see how much difference there is under those conditions.
but i am impressed with preliminary tests and would recommend the amt5k to those not wanting to spend close to 1000 on a part 15 transmitter.
anything should kick the crap out of a procaster. my opinion (never owned one) from looking them over on the net and at the fcc site. they are like the old usi trans am or lpb. ***JUNK***
if you are not going to run a large air core coil/whip like that used in the manteca magnum or a large toroid like in the amt5k then you will get dismal performance.
it goes like this certifed transmitters = hamilton or the new i am radio with external atu/antenna, uncertified kit = sstran amt5000, want to stay under 100.00 then the amt 3000.
the hamilton is still the
the hamilton is still the best “CERTIFIED” p15am tx around the i.a.m. comes in second becuase it’s certified (and supposedly the sound quality has been improved) cheaper than the hamilton (including external atu) simple to setup and with the external atu can get good range (and the only tx i know of certified with a long coaxial lead between atu and tx so even mounted high on wood with no ground lead this thing should still perform well. the uncertified kit order doesn’t need explaining.
i wish phill b or someone
i wish phill b or someone else would submit an amt5k and amt3k to HB.net for comparison and testing