"There's no doubt that the 5000 has greater range than the 3000."
NO, there is the "assumption" that it will have greater range. An assumption is NOT good enough nor is it conclusive.
Until that 5K unit is put onto a 3 meter outdoor antenna system, such as the "Ultimate Part 15 AM antenna" found on the very same maker's website, then and ONLY THEN can the assumption be either validated, or proven otherwise. But UNTIL that happens..ie the testing of this thing on an outdoor antenna system...assuming won't prove or be accepted as proof of performance, at least not in my book.
Proof is in the pudding...er transmitter/oudoor 3m antenna.
RFB
An eye doctor might help those rolling eyes.
My logic isn't connected with anything, the main thing to me is procrastination, the greatest nation in the world.
I will build an outdoor vertical with radials. True.
It will take a long time to clear the area. True.
It's been too cold to work out there so far. True.
I am busy working on a carrier current project and producing Low Power Hour No. 26. True.
When I get the AMT5000 for outdoor use it will need to be assembled. True.
I don't have time to assemble it right now. True.
Way in the future, when all this starts coming together there is forecast to be a custom made weather proof box especially fit for the AMT5000. That sounds neat. True.
The one thing that doesn't matter is now. True.
My assistant Flotilla will take any questions.
for those waiting on phil's outdoor enclosure....
here it is....
http://www.mouser.com/Search/ProductDetail.aspx?qs=vAU5MGaee3qmDc63nJzX6w%3D%3D
cb antenna dome mount kit
http://www.gijoesradioelectronics.com/scripts/prodList.asp?idCategory=126
no more excuses.
get cracking!!!!!!
I never wait for something that can be done without waiting on someone else. I used to do that...play the waiting game and never got anywhere doing that..in fact playing the waiting game always ended up in missed opportunities, and discoveries.
Given a situation where one has no outdoor antenna set up at the present time, it is reasonable to understand the waiting game...the weather, finding the underground pipes, lines etc before slamming ground rods into the dirt, clearing an area..that sort of thing.
What I do not understand is I know for a fact there are current owners out there of this 5K thing and they bought theirs to replace their current 3K thing currently sitting outside in a weather proof box NOT custom made for it, and there is yet any report on the 5K's performance off same outdoor antenna currently running their 3K.
They must be waiting too...for what is a good guess...oh..must be that box thing again.
I am beginning to feel kinda boxed in around here....nope sorry..ain't gonna happen! (breaks out of forced wait box)
RFB
Carl's testing shows that in his environment, the 5000 outperforms the 3000. That's what I was referring to - I admit it's an assumption that the same will hold for an outdoor mounted 3 meter antenna and similar grounds, but it's a reasonable one.
However, I'm just not that interested in that particular comparison, although it does show that the 5000 might (and I emphasize might) outperform the Rangemaster. If I can find an assembled board, then I will test it out in a weatherproof box. Until then, at least to me, it's yet another unproven transmitter (sorry, but scientifically, I'm from Missouri).
There is nothing scientific about Missouri, but I know what you mean.
Well with the wait and anticipation of some obscure box, I look forward to the testing of said box..meanwhile someone within the member ranks of this forum has a 3m antenna setup running a 3000 and could simply bypass that and stick the 5000 in it's current box to the side of the current outdoor box with bubble gum and hook it up and do a test.
Use shoe string, a rope, glue, a pretty pink ribbon maybe?
Testing does not require permanent installation...but I digress.
RFB
My first comparisons took place between an AMT 3000 and an AMT5000, but with medium efficiency antenna.
When I later have 3-meter vertical and ground-radials installed in a nice clear location my comparisons will again be between the same two units.
But the most serious question being asked is to compare the AMT5000 to a Rangemaster 1000, and I will be unequipped to provide that result.
Therefore it befalls someone other than me to carry forward.
Might be a good race between the two. Either way, be it a test between a 3K and 5K or between a 5K and Rangemaster, there still seems to be this holding pattern going on and I know darn well there are owners out there running Rangemasters at this very moment while having a 5K unit sitting idle doing nothing...so I see no relevant difference in the core matter here....WHY THE FRIGGING WAIT?!
Oh I forgot...it's that magical mysterious box that will make the test more viable and believable. :/
RFB
Hi Everyone
Here is the deal. Get a box mount the transmitter in the box.
Second the 5000 has an antenna tuner built in. Mount a 8 foot antenna
to the box encloser run a short wire from the base of the antenna to the
transmitter while inside the box. Close the box and mount it to your tower or
mast. Using a field strength meter tune your antenna up for max Field
strength. Then go driving around and see if the Rangemaster get out further,
or the 5000 unit.
Please note that bias on the Final transistor does matter.
The 5000 does claim to use Class E bias techniques. I am an retired
electronic engineer. Class E bias can be made to get almost 100% power
output from input power. Now if the Range master does not use a class E
bias then it will not deliver the same output power.
Most transmitters are class C bias and will not deliver a 100% or even
98% power output from the input power. I have found mos transmitter
deliver from 25% to 50% power output. This is why the 3000 transmitter
has a limitted range compaired to the 5000 transmitter.
Unless the Rangmaster uses a Class E bias it will also fall short
of the 5000 transmitter. I have heard reports of 90 to 95mw from the
rangemaster,so I am guessing it would have a class E bias circuit.
They did their homework when the rangemaster was designed,and also
when I read reports years ago on that transmitter it was first used
by the military.
Still I think the 5000 will be a really great transmitter if you do not
need the FCC certification.
I also think the procaster is another great transmitter that the 5000 can
be compaired to.
Thanks
SKW40
Your summation is quite welcome and I agree that the AMT5000 is a prominent transmitter in the mix of available transmitters under Part 15.
But the thing I wish you could expand upon is the use of Rangemaster by the military.
For what purpose has the military used any part 15 transmitter?
NOTE - I started a new thread for this discussion - http://www.part15.us/node/3475
Very interesting discussion thread and one dear to my heart. One of the things I wanted to work on this year for part15.us was to integrate product reviews into the site and from the looks of this thread, it would appear that this would be a 'welcome' addition. I put some thought into how this might work and have some ideas - treat this as a starting piont:
1) we need people to 'do' the reviews
2) we need a process to follow to 'do' the reviews so they are objective were necessary and subjective where necessary
3) we need the 'test gear' to 'do' the testing
4) we need 'products' to test
5) we need to document and publish all of the above.
First off, let me know if anyone supports the idea
Second, I know I can arrange for #4 and #5
After figuring out what #3 is, I could certainly start working on getting it
If the idea is supported, know anyone that would be interested in 'doing' the reviews?
I imagine, if interested, this group could pull together a reasonable 'test suite'?
Let me know what your thought are? - Am I crazy? (wait a minute, don't answer that)
Cheers!
Jon Paul
Dear Jon Paul Janze:
Your proposal is much welcome and the practice of part 15 would greatly benefit from controlled reviews of the kind you propose.
I can think of at least three members here, and there are probably many others, who are technically qualified to undertake such reviews.
I am thinking about prompting those persons to give serious consideration to volunteering, although perhaps they will already be interested without my saying anything.
You have this vote to move forward with reviews.
Hi Carl,
Thanks for the vote of support, I think I will start a new thread for the project and see where it goes from there. I appreciate all the help you can spare 🙂 New thread can be found here http://www.part15.us/node/3475
Cheers!
Jon Paul
Hi
I would like to see if the transmitters really meet the FCC part 15 rules
also. I have found that most say they meet the FCC rules with only a 100mw
DC input to the final. I have found out other wise. Most have a much higher
input power to the final. Some were even FCC approved and I am not sure
how that happen,but I am guessing the high cost to get them Certified talks.
As we know money talks and it takes around $8000 to $9000 for approval on
a device. Keep that in mind.
I have worked with the FCC many time and I am also a License Technition.
Anyways Most transmiters run around 40 to 50% effeceint. So a 100mw DC input
power may give you 40 to 50mw power output. In 1991 the FCC even had papers
stating a 50mw signal may cover up to 200 ft. I will try to find this document.
Anyways keep in mind a 10 volt source only drawing 10ma = 100 mw DC input
power.
I like tube circuits since tubes are high voltage low current devices.
If you had a 100 volts on your plate only drawing 1 ma then that would =
100 mw dc power input. Anyways even tubes can be bias different for better
outputs. I also do amateur radio and have designed and built my entire
station .None of it is store bought and I have talked all around the world
on home made equipment.
Anyways I have design transmitters that only produce micro watts and worked
CW on them as well. Really it not the power. It all in the antenna design.
You can have the best receiver or transmitter,but if your antenna stinks then
your whole setup stinks.
remember SWR really works on these lower power AM transmitters also.
So if most your power is being reflected back into the transmitter then
it really does not matter how much power you have.
With a 3 meter or 10 foot whip for an antenna you really need a good SWR
( standing Wave Ratio).
Here is my deal on the new 5000 transmitter. Yes it has an antenna tuner built in.
Yes it improves the match between the 10 foot wire and transmitter. Still
What SWR is being acheived with this tuner. I have seen tuners that could
get an antenna down to a 2:1 ratio but that still not a perfect match.
anything from a 1 to a 1.5 SWR is not bad. Still the 5000 does not have a
built in SWR meter. Other transmitters all they do is show a voltage reading
on a meter to let you know where the highest voltage was acheive while
tuning the antenna. Yes you get a higher field strength but still you
may have a 2:1 ratio which means you are loosing 11% of your power through
a mismatch antenna.
For example you may be getting a 100mw output well 11% of that is 11mw
So you are really getting 89mw out through your antenna. By the way a 3:1
ratio you are loosing 25% of your power. Let take a 10 foot antenna with no
matching what so ever coming out of most transmitters like the Ramsey AM 25
which has no matching at all. a 10 foot piece of wire would reflect almost
all you power because you would have a SWR of 100:1.
So a fair antenna match that would give 3:1 would look really good since
now you would be only loosing 25% of your power and not 99% of your power
through an antenna. Still we are looking for the best. a 1.5 : 1 SWR would
only loose 4% of your power which is not to bad.
This is why I say when a transmitter says it has a built in Matching system.
We really need to know how well does it match the antenna to the transmitter.
It would be nice if some of these high cost transmitters actually would provide
a built in SWR meter so you could see how well the antenna is match to the
transmitter. Even some high cost CB radios have built in SWR meters as
well Amateur radio equipment. This is so you can make sure the antenna is truly
matched to the transmitter.
It a thing for thought.
Thanks
SKW40