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What did you do to your Part 15 station today?

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What did you do to your Part 15 station today?

I have seen something similar to this on some motorcycle sites.  Sometimes it is interesting!

Today I finished building a coil similar to the plans on the SSTRAN site.  I prepped it for install, only to find my antenna analyzer wouldn't go down low enough in frequency.  Now I am scrounging thru my hf swr meters to see if any of my stuff will read that low power and frequency.   Needless to say, I don't usually do qrp!

I did install it and "roughed it in", with the TH 5,  If nothing else, it looks cool, and it may be a little more efficient.  But, not being able to verify swr, I am not sure.

Decided to add a note:  The TH is mounted in the toolbox on the roof at my warehouse.  It was using the internal tuner with the 102 in. whip. When I added the coil, I flipped the switch to external and installed a short piece of coax from the F connector.  I am in theory, in compliance for length of antenna and ground (supplied thru the coax shield to the toolbox).

Happy 4th of July to all!

Craig

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a spec-analyzer is your best friend here

us it to peak the relative field strength. i use mine with a belar loop antenna to get absolute best peak f/s from any antenna design i may use on medium wave.

 

if you don't have one a loop can be made and a cheap spec-an can be had from china via ebay for about $400.00 which is suitable for our part 15 purposes.

 

Part 15 Engineer

Hindsight is 2020

I'm not a democrat or a republican, i'm a common sense moderate progressive

 

please don't forget to register and vote

Would love to have a spectrum analyzer..maybe now is the time!

I have been considering getting a spec analyzer for several years.  My wife endures my hobbies and expenditures, be it motorcycles, radio stuff or whatever...

Speaking of expenditures and still related, I just bought an assembled sstran AMT 3000 off ebay.  I will be making another trip on the roof in a few days to install and compare to the range of the TH 5.    

I want a AMT 5000, but maybe next month when I get bored with the AMT 3000, and realize I gained no distance or anything over the TH 5. (I hope I am wrong)

 

Working on getting our small town of <4000 local programming.

My TH units always outdid my

My TH units always outdid my SSTran in coverage. Audio quality is a whole 'nother story, that SSTran was one of the best sounding transmitters I've ever heard.

Lately I've been tweaking the Optimod 9000A output to get as close to 125+% as possible. I have to tune by ear which kind of drags out the process.

SStran Coverage

As I was reading thru the many comparisons and comments about SSTRAN, I noticed that the TH seemed to out perform it in distance covered more times than not, and yet the SSTRAN sounded better. 

I figure I will duplicate that same scenario here.  But, the improved audio will make it worth while until I decide to move to the next transmitter. 

I will have to admit, this micro power AM has brought about some propagation scenarios I hadn't forseen.  

Working on getting our small town of <4000 local programming.

"I will have to admit, this

"I will have to admit, this micro power AM has brought about some propagation scenarios I hadn't forseen." 

Man isn't that the truth. At such low power levels our LPAM signals even seem to take on some line-of-sight VHF characteristics in addition to the usual MW propagation. I have noticed the more traditional setup you have the less weird the LPAM signal gets.

Reply to #6

Stands to reason that at "our" power levels AM can take a line of sight transmission....because you don't have enough power to go beyond line of sight or have any ionosphere bounce.

 

Mark

About Reply 2 above (Spec Analyzer)

Use it to peak the relative field strength. ... if you don't have one a loop can be made and a cheap spec-an can be had from china via ebay for about $400.00 which is suitable for our part 15 purposes. ______   Just to note that much less expensive, yet suitable receiving hardware for this task is sold by Tecsun and others (at US $50 or so). Such hardware includes both the receive antenna, and a receiver having a front-panel display ~accurately showing the relative fields of received signals on a given frequency.  One example is a Tecsun PL-310. However they CANNOT be used to measure/prove compliance of fields at a given distance to those permitted by FCC Part 15, or any other regulatory body.

What I Did Today...

The antenna for my AM station is installed next to a wooded area and because of the huge amount of rain we have had this spring and summer the bushes have grown to where the branches were in contact with the radiator. I spent some time trimming them back and the field strength measurably improved.

Neil

Daytime vs night time propagation

I made a comment earlier about the idiosyncracies of micropower transmissions in the AM broadcast or medium wave band.  We do not have enough power to "bounce" signals off the ionosphere, and daytime signals for Medium Wave would be limited to ground wave anyway.  Yet, we gain distance (or at least I do) in daylight hours.   Much, as it was mentioned earlier, like "VHF line of sight" characteristics.  

I have a mental image of my flea powered station not having enough power to fully develop the full wavelength and it kind of droops as it starts up the peak of the wavelength.  Thus it acts less like it should, or does it?  Most people blame poor night time reception of their LOCAL AM station on power reductions etc for night time service (true in many cases).  But, heated daytime conditions allow the medium wave frequencies to travel faster/better for groundwave propagation, so I guess all is normal????  This is an area, that some of you experienced AM Broadcasters might expand on. 

What have I done to my station today?   Corrected some station id entries in RadioDJ, which I am still learning, but starting to like a lot.  It is running on one old laptop, and ZaraRadio is running on an even older laptop as standby, or when I am experimenting with transitions I change the programming source to ZaraRadio. 

Working on getting our small town of <4000 local programming.

The waves are still fully

The waves are still fully formed. The low-power just makes any noise at all extremely noticable. During the day there is less noise on MW (excluding electric grid noise), at night the noise floor raises substantially then slowly falls as the electric grid is used less and less overnight.

Heres a fun oddity I noticed today, my daytime coverage is fantastic and extremely strong in town. That being said, the signal STILL ducked on me when I drove past a utility trailer parked about 30-50 feet from the transmitter. Also fun note, the signal only ducks under a few power lines not all of them. In fact, in the next town over the lines enhance the signal. Gotta love AM!

Fully formed waves..

It is interesting to see the way the signal conforms and moves with the terrain and its obstacles.  I have observed the same thing here.

BTW, I am amazed at your coverage area.  I am doing good to get 2 blocks here consistently and I lose that at night.  We are not as flat as you are there in your part of the state, but I definately need to work on things a bit more here to get some decent coverage.

Working on getting our small town of <4000 local programming.

A word of caution to all:

Make sure your station is "fuctionally compliant." And no damped waves.

Druid Hills Radio AM-1710- Dade City, FL. Unlicensed operation authorized by the Part 15 Department of the FCC and our Resident Hobby Agent.  

Damped waves...

My radio wave roller coaster has lumps in it.  Or maybe they are melting in the heat.  

And to think, there are comedians out of work.

Waiting on the Sstran Amt3000 to show up.   At which time, I will do a short term test to verify what I already suspect.   Then I will initiate a move to my residence and set up the antenna in the back yard, in a more conventional installation. 

My metal roof installation, though appealing, and convenient, has disappointed me.  If I were to bend the rules with additional grounding etc, it probably would exceed my expectations.  But, I am trying to play by the rules, and I also am enjoying the challenge of getting the most out of this with the parameters we are given.

Setting up at home will bring about new challenges, such as being able to listen at work, since I have my doubts about reception in my building 3/4 mile away.  I also do most of my programming changes during the day, so that will become a remote thing.   Perhaps I will stream my audio back to work.

Damped those waves...

Working on getting our small town of <4000 local programming.

Before I had the power levels

Before I had the power levels dialed in correctly I could pickup my part 15 AM in front of the full power's studio 5 1/2 miles away, albeit a weak signal. The same setup running at max power transmitted over 10 miles. Currently at 100 mW the transmitter goes 3-6 miles of which only the first mile is very strong, the remainder is fading gravy although comfortable in car listening lasts for awhile.

Could you describe how your

Could you describe how your transmitter-ground-antenna is setup?

Druid Hills Radio AM-1710- Dade City, FL. Unlicensed operation authorized by the Part 15 Department of the FCC and our Resident Hobby Agent.  

7.195

When are you on?  Also, do you live at the feed store?

Druid Hills Radio AM-1710- Dade City, FL. Unlicensed operation authorized by the Part 15 Department of the FCC and our Resident Hobby Agent.  

7.195

When I see that (7.195), I think of where I usually hang out on HF.  Haven't been active much in the last month or so, haven't been in the groove.  7.195, coincidence or no.... 

Working on getting our small town of <4000 local programming.

OK.  I will tune around on or

OK.  I will tune around on or near that frequency. Qustion two: Do u live at the feed store or across the street at Sonic?

Druid Hills Radio AM-1710- Dade City, FL. Unlicensed operation authorized by the Part 15 Department of the FCC and our Resident Hobby Agent.  

Not at feed store.. @wdcx

I realized the coincidence was too much.  So I figured this might have been directed at me.  I am actually up the street from the Sonic/feed store.  My facilities are near the Green Frog, so I am often there!.   Google Earth is not quite current on drive by.

Working on getting our small town of <4000 local programming.

"Could you describe how your

"Could you describe how your transmitter-ground-antenna is setup?"

I'm going to assume this one is for me.

The transmitter simply sits on top of an 8 ft pole surrounded mostly by farm land. For "extended" coverage there are 8 semi-buried radials and one centrally located ground rod. Oddly enough the loss or addition of radials or the ground itself doesn't seem to have much of an impact on signal strength. I'm beginning to wonder if maybe the metal pole is acting like some sort of ground coupler or shunt fed antenna.

3-6 Miles would cover my town

3-6 Miles would cover my town of Deltaville.  Surly nothing to cry about and I'd be happy with that.  Must find a way to have a stealth antenna and still have that sort of range.  I had a few folks say they'd listen to me even on AM if only they could hear me further than say 1/4-1.1 miles away.

Progressive Rock (Album Rock, Deep Tracks), Classic Rock

http://thelegacy.shorturl.com

More Power for Hobby Broadcasters

http://the-initiative.boards.net/

Part 15 AM Coverage Expectations

Below is a chart showing the groundwave field intensities produced for the conditions shown there.  The d-c input power to the Class E final r-f amplifier is 100 mW.

Today I unboxed my new SSTRAN AMT3000

I set the frequency and will begin testing with it.  Nice looking device.  Hopefully, I will get time to set it up for the external coil and mount it in place of the TH...

Working on getting our small town of <4000 local programming.

Craig said: "  I prepped it

Craig said: "  I prepped it for install, only to find my antenna analyzer wouldn't go down low enough in frequency."

John said: "Use your rig's S-Meter, adjust the sensitivity of the receiver so it can just detect the signal from the transmitter and adjust your taps until you find the one that peaks the signal on the receiver."

Druid Hills Radio AM-1710- Dade City, FL. Unlicensed operation authorized by the Part 15 Department of the FCC and our Resident Hobby Agent.  

Other Considerations...

"... find the one that peaks the signal on the receiver."

______

Just a heads up -- such signal peaks also will occur for systems that exceed the limits of Part 15 AM, and which might result in an FCC citation (NOUO).

Peaking receiver

First, thanks Rich for the concern!  From what I am seeing, this thing is pretty anemic on power from what I am seeing in the shack while testing.

Initial thoughts, it sounds pretty good.  Been playing with the supplied antenna, and even tuning a couple of external antennas, that are probably not compliant, but did not yield outstanding results.   I am back on the supplied antenna at present.

Tomorrow, depending weather, my temperment, etc. I may attempt an install in place of the TH.   But, as a priority, I have to work on my office A/C.  It quit today...only two weeks old.  I am not impressed when I sweat at my desk. 

Did I mention this thing sounds really good when in range?

 

Working on getting our small town of <4000 local programming.

Biting ones toungue

It Hz , you know?

 Barry of Blue Bucket Radio 1620 AM  - http://bluebucketradio.com - WQYY 664

No AMT3000 install today.. but

I did go up on the roof with my old yaesu vx-2 (I forgot I had it).  The VX-2 is a multi band pocket sized receiver/transceiver that picks up most anything, just not very well.  But it was perfect for this task. 

I removed the antenna and peaked the antenna settings a bit more.  Mostly, I got rid of the distortion that showed up after my coil install.  I am sure it was from the mismatch that was causing RF to go back into the transmitter.  That made things sound pretty good again on the TH 5. 

Distance increase?  Not sure, but it did sound better at the house in the truck.  But it could be wx/atmospheric conditions.

I must now focus on A/C issues as it is already heating up. 

And yes, it Hertz.  You might even say it KillooHertz...   Comedians probably out of work somewhere!

Working on getting our small town of <4000 local programming.

Some Antenna Work...

I finally put up my omni directional antenna for the FM BCB.  I use it to seek out Part 15'ers and to monitor my yard caster.

by MRAM 1500 

Charter Member - Association of Low Power Broadcasters

Chairman - ALPB

Ran across a neat AM station on the internet, or?

Or is that an Internet station that happens to broadcast on AM 1260. Ok, so its not related to my part 15, or is it?  I retransmitted the stream via the new SSTRAN at home for my personal listening pleasure.  For those that are curious,  KYA 1260.

Regardless, It is a neat station from my viewpoint.  Plays oldies.  Had a Beatles show on yesterday morning.   And it even plays some old advertisments.   I even heard an advert for the "new" 1972 VW.  I realized that I was not annoyed so much by the presentation of those adverts as I am now days when I listen to the "busy" almost ADHD driven stuff.  Odd thing is, that I listened to KYA for several hours and am not sure I heard a current advertisment.  I wonder how they pay the bills?

I changed the A/C unit in my office yesterday, that is where I program my part 15 station currently.  Today I am enjoying the cool air blowing across my face while changing some of the shows and music for the day.  Oh, and doing things that actually make me money.

Working on getting our small town of <4000 local programming.

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