AM Antenna Solution

I wouldn't be so quick to judge others here on this Forum, based on responses to your initial inquiry, which you yourself admit was not framed appropriately. Stick around, you might be pleasantly surprised at how helpful most people here can be.

If you do decide to experiment with the 160 meter antenna suggestion, I just wanted to remind you that the total length of the feedline, antenna and ground wire has to be less than 10 feet or 3 meters to remain compliant with Part 15 rules. That more than likely means that you will have to mount your transmitter at the base of the antenna, and use a very short ground wire. Good luck.

Heh-heh ... well, of course, laws of physics apply. But, there are just an unknown number and effects of variables on such low power in any given Part 15 installation. Therefore, experimentation is part and parcel of any such installation, regardless of whether it all comes in a box, or is built from a collection of parts.

And of course a major factor is the receiver. Compare a cheap little clock radio with a quality general class receiver with a longwire antenna.

Quote..
"Yeah?.. build two! I'd like one for my AMT3000"

I can do that. Contact me..

Love that graphic 12vman!

I agree with the original posters premise that out of the box or simple isn't what Part15 is all about.

It truly is a lesson in efficiency and optimization.

I encourage the poster to keep trying, but get some local hands on folks who understand radio and are glad to tinker. Everyone needs a sidekick.

That's how I feel about the power grid. Been running on 12 v.d.c. since '89.. Hence, 12vman..

Yeah, this hobby is complicated and takes a lot of time and effort. Even if one had a prebuilt antenna, it still doesn't guarantee good range. Lots of variables involved and ya gotta know what to work on to get that extra 1/4 mile..

A hobby is a hobby. Most avid photographers didn't start with a lab to do negatives. They bought a camera and had the film processed by someone else. Some get the fever and before ya know it, there's a dark room in the basement..

If you want this hobby to grow, ya gotta forget what you now know and remember how you got your knowledge, and nuture the curious..

Wow. You know something; I think I just found some good folks around here. 🙂

Thanks so much for your patience guys and please forgive my previous lack thereof...

I've been reading a lot of radio boards over the years and saw a LOT of flame wars and many who were 'high and mighty' and many who did not get treated fairly and I guess I was a bit unsure chartering into territory where I am definitely not an expert compared to some others and just genuinely wanted help out of frustration.

I totally get the experimentation aspect of this hobby and for the most part, I have been having lots of fun. I guess I just wanted something that worked better than what I had and I will admit...a big part of me thought I was doing something wrong. But now after reading all your posts with sound judgement, I guess I'm not too far off. 300 feet sounds like what I am getting. My station can be heard up until the property line....then it fades very quickly.

Someone had asked about the Procaster I had. I'm not entirely sure what exactly the grounding issue was. As soon as I connected the unit to ground, all I could hear was a very loud hum....so loud, that it washed out the rest of the audio. Now, I know what you're thinking....get a better ground, right? Well, I did. Pounded a couple of copper ground rods into the ground....same result as the house ground.

I never had this much of a grounding issue with anything else so I figured, and Chez Radio agreed, that it was a faulty TX. However, the silver lining from that ordeal is it led me to buying the SSTRAN. It’s ultimately what I wanted in an exciter anyways because of the ultra-high fidelity audio. The Procaster was purchased primarily because it came with everything ready to rock and roll (including the antenna, which of course, was my biggest concern). However, I am much happier with the audio of the SSTRAN than any other AM TX I’ve ever tinkered with. I just only wish I could throw the signal a bit further….legally.

Looks like I’ll be PMing some of you here. I totally appreciate the help and once again, sorry about the OP. 

I would have built you an antenna just so you could find out for yourself. My offer wasn't out of frustration, just tryin' to be friendly and help you along..

I have a lot to learn myself but if there's anything I can do to help, just let me know..

Hello 12vman,

Careful, I may actually take you up on your offer!

Sorry for my delayed responses guys. Things were pretty busy over the holiday season.

I should also mention that a couple of my limitations here are space and the fact that there is a commercial 50 kilowatt AM about a mile away. But, the good news there is last year the station received approval for its relocation and that should hopefully be happening this year. It will certainly clear up a LOT of reception problems around here, not only for my little station, but for general AM listening as well. There is a lot of splatter being this close to the transmitter.

Okay, so here is some exciting news, over the holidays I ordered an SSTRAN AMT5000. From what I have read, users are reporting improved range therefore I am looking forward to building it and setting it up.
I also moved my station up the dial to 1650kHz. Going above 1610 is something I’ve always tried to avoid simply because of its obscurity in my area. Radio listeners here are not used to tuning to that part of the band. The highest anyone here has ever had to tune on AM is in the 1100kHz range. 1580 was already very far away from anything else. Although I am sure it’s not a huge issue these days, older tuners may not be able to tune above 1610kHz and so that also influenced the decision. 1580kHz was chosen because that was the quietest high frequency channel below 1610 I could find. (However, other frequencies were tested as well)

Well now there seems to be a lot of electrical interference on that channel and the signal gets washed out at night sometimes. Therefore, it was time to relocate on the dial. Along with this move is a format flip to a more contemporary music playlist to reflect on more localized talent.

While doing some testing over the holidays, I was once again amazed at the audio coming from my AMT3000. I use a Carver TX-11a tuner to monitor my broadcasts. You haven’t heard AM radio in all its glory until you hear it through this tuner. During the testing I also fired up an FM transmitter with the Stereo modulator turned off. Flipping between the AM and FM feed on the TX-11a resulted in almost identical audio from a quality standpoint. There was higher audio response at the high end on the AM feed because the treble boost is enabled on the AMT3000. (FM TX pre-emphasis was set to a 75 µs time constant, both transmitters receiving the same feed) Otherwise, the full audio range is heard over the AM. That is what I love about the SSTRAN product, it sounds great. However, I always felt the signal could use a little punch. Hopefully the AMT5000 will provide a better signal to the antenna.

Speaking of which, I’d still like to pair up the AMT5000 with as efficient of an antenna as possible and I’m looking for some help. Is there a PM function on this board?

"But now after reading all your posts with sound judgement, I guess I'm not too far off. 300 feet sounds like what I am getting. My station can be heard up until the property line....then it fades very quickly."

After going over your experiences with various transmitters and antennas and getting nowhere, I would start looking elsewhere for the cause of the problem.

Taking note of what you said about the signal dropping off at the property line...what exactly surrounds your property..ie a chain link fence..or barb wire fence...or ???

What is the dirt condition..ie ground conductivity rating. Is it very dry, is the surroundings clustered with trees or brush or clear.

The others are pretty much on the mark in regards to a works no matter what pre-built antenna system...does not exist as even the two that are out there do not simply work magically right out of the box..simply because every location is different, thus different problems will be encountered which requires different solutions in order to get the system to perform.

You tried complete out of the box systems with the same results and now a SST unit with only 300 feet and a drop off at the property line. I believe the problem isn't in the transmitters you have tried, its something else on and within the property that's causing the poor performance.

I get the feeling that your going to get the same poor performance with that SST unit even beyond the simple wire because there is something else causing the poor performance..something absorbing the signal...say a bunch of trees/brush, outer parameter fencing, poor ground conductivity etc etc.

Good Luck.

RFB

Yes, but it is not working at present and a fix is being sought.

Neil

RFB has suggested that something other than the transmitter may be causing the limited range you reported and he is probably right.

Forgive me if I repeat things you already know but I want to cover some basics. The range depends essentially on the amount of RF power radiated and the sensitivity of the receiver. I have found that an inexpensive portable receiver will give a range of hundreds of feet where a car radio will hear the signal for about a mile. Proximity to utility lines can also affect the range, both positively by acting as a receive antenna and negatively by producing interference.

The biggest factor at the transmitter end is to get the antenna system into resonance. This will make a tremendous difference in range and unfortunately is not a plug and play experience. The best approach is to follow the manufacturer's instructions on tuning the system.

Realistically, if you install an antenna with ground radials and the transmitter at the base of the 3 meter antenna at ground level you can achieve a range of about one mile with a listenable signal on a car radio with a transmitter such as the AMT-5000. This has been my experience with a transmitter similar in efficiency to the AMT-5000.

As mentioned by RFB, other factors can affect range but you should be able to do better than you have reported.

Neil

The discussion is right on target and I think I can contribute another piece of the puzzle to help get a big picture of what is happening.

Is "the edge of the property" uphill from the transmitter?

I have found in my experience that AM signals do not want to go uphill from the antenna, and I have done a lot of experimenting with this problem, because my location is literally in a bowl, since every direction is uphill from here.

I think the AM radio industry knows this, because their towers are always on level ground or on high ground, not down in valleys or depressions.

Grounding really helps. By running radials extending in length as close to 1/4 wavelength as your property allows, the "throw" of the signal improves dramatically.

And, as was said, getting the antenna system in resonance does the rest.

I have found in my experience that AM signals do not want to go uphill from the antenna.