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SpitFire AM Transmitter

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Reply to 2 1/2 miles on AM

Very impressive! Didn't think that was possible. Watched video.

But note that that type of set up requires having your own house and large property, not only that but a way of getting the power for the transmitter and audio to the transmitter from the house. Where do you get the radial system?

Just saying that not all have the place to do this and this is not typical.

Also I'd like to see what happens when a big storm comes and 1million volts from lightning strikes.

Not trying to be negative here but this set up is not an option for everyone.

I'm sure that if I was in a rural area in the right location with all flat terrain and set up my BETS-1 Decade transmitter 20 feet up or on a roof and powered it with 30 feet of extension cord and audio feed, in a weather proof box I'd get some very good range also.

You have to be fortunate enough to be in the right place and have the access to do the perfect set up.

 

Mark

Part 15 AM Range Benchmarks

RE:  Reply 28 of this thread

I always get at least 5 1/2 miles of coverage during the day from my AM.  ...

That is much better than expected, even for a Part 15 AM system installed in open country having the highest value of soil conductivity present in continental North America (30 mS/m).

Below is a chart showing the fields produced for various distances and soil conductivities from a Part 15 AM system installed and operated in full compliance with FCC §15.219.

A very good receive system in an area of very low radio noise level and no co- or adjacent-channel interference might produce listenable/useful (but noisy) output audio from an arriving field intensity of 50 µV/m.

The chart shows that at 2 miles, 50 µV/m is met or exceeded only for 15 and 30 mS/m earth conductivity.

Field intensities at distances of 3 miles and beyond are significantly below 50 µV/m for all values of soil conductivity.

 

Watts Don't Make The Broadcaster...

"The SpitFire, SSTRAN and other micro AM transmitters will NOT make you a broadcaster."

You are correct!  Even a 50 KW torch does not a broadcaster make.  That's simply the hardware which makes the "broadcaster" available beyond the sound of their voice.

There is a joy in tinkering with radio.  At 10 years of age I was "broadcasting".  Yes, it was only within my parents house but just as Rush Limbaugh, our Remco Caravelle transmitters provided us with the means to "broadcast" our programs to radios in far distant places like the basement, kitchen or garage.  By definition, that made us broadcasters.

I ran into the same narrow point of view when I put our City LPFM on the air.  Our station is a staion with no format.  We don't fit the commercial boys idea of a pigeon-holed top 40, classical or hip-hop station.  They said we were a Pirate station.  They said we wouldn't last 6 months.  Over two years later, here we are providing news, weather, music and PSA's.  Most importantly our high school developed a "broadcast" curriculum and students produce a one hour show which airs weekdays.

And you know what?  I get favorable comments about our "no format" station from our listeners.  Maybe it's a niche market share but they are listening.

Broadcasts may be statewide, local or just within a few hundred feet but you are a broadcaster by virtue of the fact you are sending content by radio regardless of the coverage area.

 

by MRAM 1500 

Charter Member - Association of Low Power Broadcasters

Chairman - ALPB

Interesting Discussion

Wow! That video shows what the SSTRAN can do! I would say that the Spitfire is comparable.

I still have to experiment with the Spitfire. Try the ATU and tune it. 5 1/2 miles? My gosh. 1 mile @ night?? I ain't even gonna ask...

Doug

Admittedly my coverage is

Admittedly my coverage is highly unusual, Hamilton Rangemaster in a rural area with low to no RF noise. I have a sneaking suspicion the nearby fertilizer plant has some effect on my range. Not to mention the car radio has a very impressive AM side. My closest Co-Channel is in Iowa I believe, my signal is usually decimated by adjacent channel splatter from both sides at night. Loud processing helps.

The biggest difference is the Crystal control allows the carriers to not beat against eachother which reduces nighttine noise. The SSTran, Spitfire, TalkingHouse, and several others use PLL tuning which can have enough drift (as slight as it might be) to have the carriers beat and reduce night coverage. This is the grumbling warble sound you hear at night. If the drift is great enough it'll whistle.

Yes! AM @ Night Sux

So that's the reason. Thanks Mighty! Crystal, eh? Hmmm...

Doug

Agree Whole Heartedly

"Broadcasts may be statewide, local or just within a few hundred feet but you are a broadcaster by virtue of the fact you are sending content by radio regardless of the coverage area."

I agree, it's still broadcasting.

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

Tree's, Rocks and Hillbillies

In response to post #32? Rich, how would a signal fair using the same formula you shared in your post in say a rural , mountainous wooded area? With very little effort on my part and using either one of my two transmitters on AM ( the sstran amt3000 or TH 5.0 ) I am able to cover 1/4 mile in the open, BUT, part of that coverage is from the power lines and not by conventional over the air transmission.

The current setup is the SSTran AMT3000 wired to a 9 foot aluminum conduit, ground is fed directly into the house wiring via the supplied power supply (walwart) and audio is fed to the AM Transmitter via a receiver tuned to a 89.7 FM. The FM STL is trivial and should not be included as it really isn't a physical connection to the AM transmission system. 

The bucket that houses all of this is sitting above the soil on a wooden deck about 12" from the soil. What is hurting my signal here more than anything?

The fact that I am using the conduit instead of the supplied wire antenna? No coils.
The rocks in the mountains surrounding me?
The tree's on the mountains?
Or the fact that the system is not above the terrain around me which for the most part is 800 to 1200 feet higher than my property?

I am just wondering how viable a well tuned antenna and transmitter would be in such a diverse terrain. Some say trees help propagate AM signal's, i have no way of knowing.



Barry of BBR 1620
Deep in the heart of Red Bird National Forest

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

Beat interference, it sounds

Beat interference, it sounds like thunder rolling in on frequencies like 1450 and 1490 most nights. Transmitters are more frequency tolerant these days so you don't hear the beat tones like in older times, which sounded like low growls on big speakers. Maximum growl frequency should be forty cycles per second, with the allowable frequency tolerance of +/- 20 hz on the AM broadcast band.

There was a proposal put in the AM improvement pot a few years ago that all AM stations should frequency lock together nationwide. Apparently is wasn't put into place because of the expense that would have fallen to each station or group, and maybe it wasn't deemed as an important enough thing to do.

Frequency syncing isn't a new idea, I read long ago in a 1950s engineering reference book about the BBC trying it.

I've heard close-transmitter frequency syncing a few times, on traveler's info highway stations. Listening to the first, you'll start to hear the voice from the second, far off in the distance. In this case they were running seperate messages. The distant station's voice gets louder and louder until they're about equal, and it sounds like a mash of two people talking, then the first station strarts to fade out and the second becomes the dominant. All the while there's no beat between the carriers, no pulsing, it's like one signal.

I thought that was pretty cool, but how would it work on multiples of widely spaced broadcast stations? My thought is it would help, since carrier beat is an issue, with the carrier being the strongest part of an AM signal, but what about interference zones where the carriers are out of phase between stations?

MRAM 1500, I had similar

MRAM 1500, I had similar humble beginnings with kit transmitters on AM and then FM, wanting to be a DJ and it was fun with friends, and getting together to broadcast, and I'd draw up playlists and announcements, but usually it would degenerate into laughs and getting silly, and we'd have to just shut down.

Even in the early times we were thinking about more range, getting a signals to a friend's house down the street, and at one time it was a constant thing to think about range and "getting out".

I put longer wires on the AM transmitter, we upped the voltage on the FM from one to 3 nine volt batteries in series to get out more.

Even now it seems like so much is about range, and when I get a new rig, one of the first things that's done after tuneup, is to go for a range check!

These days I'm not thinking about being a star on the airwaves, but I want the range, so that people can have a chance of hearing my music selection of "anything goes" mixed bag, and my engineering efforts at getting good, low distortion sound.

The payoff isn't in 30 feet of range, the self satisfaction of hearing what's been achieved is good, but it's only part of it, now I think others might benefit from the broadcasts, and if they don't like it, they can change the station. It's just like having a website, on offer but no one needs to go there or stay if they don't want to.

I'm glad that your LPFM is doing that mixed bag format, I love that kind and used to hear it on small stations, like 10 watt FMs that didn't fuss over the music, just played it. Radio went so commercial that variety was stamped out by formatics. If the underground stations could have held out, we'd have a listening audience that might understand music and program appreciation more these days, a more demanding and interactive audience.

Sure the conglomerates of national broadcasters have stations that are number one rated, and it's because they control all of the top signals, and the alternatives have been drowned out.

That's a reason I think it's great to have a multiverse LPFM like that, it will revive radio's sleepyhead listeners that there is something else out there.

About Reply 39

... What is hurting my signal here more than anything? ...

It might be that the "ground" conductor of the house a-c wiring is not very effective at radio frequencies.  You might try using an 8-foot copper-plated ground rod driven vertically into the earth directly below your 9-foot aluminum conduit antenna -- connecting the top of the ground rod to the chassis of the transmitter.

If the earth there is too rocky to drive in a ground rod, you could install a set of horizontal radial wires on or just below the surface of the earth.  The common point where the radials are connected together should be located directly below your antenna, and connected from there to the chassis of the transmitter.  You might start with 10 radial wires each about 15 feet long, evenly spaced.  If earth conductivity is poor at the transmit site, more than 10 radials might be useful -- even 30 or more.  The radial wires can be either insulated or bare.  Copper or at least copper-plated wire is best.  Maybe use at least 16AWG wire or larger (solid) for the radials.

... I am just wondering how viable a well tuned antenna and transmitter would be in such a diverse terrain. ...

Trees, houses and small hills don't much affect the propagation of signals in the AM broadcast band, as they are small in terms of the wavelengths used.

More important is earth conductivity at and within a mile or so of the transmit site.  Low conductivity reduces the field intensity of groundwaves as they propagate along the surface of the earth.  But there is nothing one can do to improve that condition except to move the transmit system to an area having better earth conductivity.

Nate Crime you said a

Nate Crime you said a mouthful there. I think one of the reasons people have become so content is because they know no other format now. It's all lumped into the same top 40 rap hip-hop and one of the Rock. Classic rock and classic hits have been jumbled up into classic hits but people think it's really classic rock. There is a major difference as I have tried to state a long time ago. But most people have forgotten because the underground stations that used to play The Deep tracks are no longer a part of the regular Airwaves.

 

In April of this year an LPFM station on 103.9 called WWND came on the air in White Stone Virginia. They began a format of oldies and some real classic rock mixed in there. Whoever owns the radio station really did a good job in music selection. We're talking anything from Frank Sinatra to the Grateful Dead and lots of the older folks really enjoy that station. I can pick them up almost all the way to Gloucester Virginia on a car radio. In the morning they actually do a show till sometime after 2 p.m. and the DJ is pretty cool. I talked to him a little bit about his station and about how the radio station started. He said a small group of radio Buffs started that station along with a few down in Florida. They got success and they don't ever want to become corporate radio because there's no fun in it.

 

LPFM at least bring some small communities back up to what they should be. There are some really good stations out there that do it for the passion of radio. The trick however is to get the funding necessary to do it right and keep it going. Some of the LPFM's struggle for success due to the fact that many folks rather sit and do nothing instead of help try and fund a station that they really like thinking that somebody else will do the grunt work for them. This is been a case I have seen in the radio hobby itself where people want change but rather sit back and let someone else do the work and thus nothing gets done. This is why many of these small stations will ultimately fail in the long run unless somehow stations can be set up cheaper.

 

The attitude where if you're broke don't start a station it's really not a good one because it keeps many folks from doing exactly what we're trying to do. Yes having lots of money and a huge studio and the best mixing board and the best audio processor possible will make your station sound great but there are ways of doing things on a budget. You just have to look at all the options and keep your eyes open that's part of being a hobbyist as well. I don't expect things to fall in your lap as even my internet station was a large struggle at first. Many folks that didn't support me at first kept telling me to give up because I would never have decent enough bandwidth to support the station that I want. But I kept plugging away at it and things are going great now. You just have to have the drive and determination to do things and get things going the way that you dream of having them go. It's not going to come easy it won't fall in your lap but keep plugging away and eventually it will come to pass.

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

http://thelegacy.shorturl.com

More Power for Hobby Broadcasters

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

Radio is without a doubt a

Radio is without a doubt a lot better when you can tell the on-air folks are having fun. Funny thing about Classic Hits and Classic Rock, If I'm not mistaken when the format first rolled out it was called Classic Hits. I'm not entirely sure when Classic Rock became the defacto term for the format.

Radio is an extraordinarily expensive business, that is an unfortunate fact that cannot be overlooked. It gets even more expensive if you dare have on-air talent, then finding on-air talent that isn't an egomaniac is another problem. Based on my experience, hiring and keeping air-talent is the most frustrating and exhausting part of the job. (Aside from bill stickershock)

Reply to Post 16(ground)

You can try a power supply with a 3 prong connection with the ground like a computer monitor "block" style 3 prong power supply or other adaptor with the 3rd prong(but block style is the best) and see if any different. Most of these kind come in 12 volts.

 

Mark

Expensive

"Radio is an extraordinarily expensive business, that is an unfortunate fact that cannot be overlooked."

No doubt Mighty. Plus, time consuming. Dangerous too, doing tower work. As far as hiring and keeping air-talent, ha! Been there, done that! Frustrating and exhausting is right! Today? That's a BIG nope! But...that said-

I have the equipment. The music. It really costs me nothing now. Just my time. But I am buying equipment, so I guess saying it costs me nothing would be incorrect. I spent $200 on an SSTRAN and a SpitFire. I spend money on my hobbies, so...

Good equipment is terribly expensive! A good pro board is over a thousand. QRK/Russco turntables are at a premium. A good Orban comp/limiter like the 424a starts at over $600! Does anyone use cart machines anymore? I use a laptop with Zara.

Doug

Classic Hits vs. Classic Rock

mighty1650, in the commercial radio biz, Classic Rock is *rock*:  Lynyrd Skynyrd, Ozzy, Tom Petty, Stones, etc.

Classic Hits is what we used to call "Oldies".  It can be the Bee Gees, Grass Roots, even the Monkees.

Not that the world will end if the terms are used interchangably.  :-)

"Good equipment is terribly

"Good equipment is terribly expensive! A good pro board is over a thousand. QRK/Russco turntables are at a premium. A good Orban comp/limiter like the 424a starts at over $600! Does anyone use cart machines anymore? I use a laptop with Zara."

Man ain't that the truth, though on some facebook groups you can sometimes get good vintage broadcast gear at a more reasonable price. The most insane pricing seems to involve the AM Optimod units, while fantastic processors they are 30+ years old with unobtanium electronics.

There is some really good gear available under $1,000 but not that much under. The Inovonics 223 runs about $850, Hamilton runs $500-800, new mixers are in the thousands, pro sound cards run $300+, etc. The really good stuff costs a lot but price really does equal quality in the radio industry.

Am Optimod components are

Am Optimod components are certainly available, it's just that people don't even want to look for them !

I still repair/upgrade 8100 fm and 9100 optimods, no problem.

When looking for digital broadcast processor parts, things get a bit harder, as they are harder to trouble shoot, without knowledge and expensive test gear.

The Inovonics 222 is an over rated box when used by itself, it is an add on compliance box, people forget that.

By the time you couple up non broadcast gear to a 222, you might as well buy a used broadcast processor.

The phrase "less is more" always makes me laugh, that saying is true when using non broadcast type gear cascaded together.

Paul.

Good equipment

fortunately I have kept my expenses down.

But you still need some means to get a good transmitter. The Procaster AM transmitter considered one of the best is $700 US? But this also has on board compressor limiter which is adjustable, eliminating the need for a separate compressor. With FM the Decade is probably the best and is $500 for the mono model(MS-100) which will get you farther and will still be working 15+ years from now and is made in Canada...You can get cheap stuff but it won't last long and sound the same.

My costs are for the Decade(recently purchased a new one, was using an older one in the plastic case before.), but have others I've used too, so some additional expense along the way. $250 for an RNC compressor and my audio source is with a Sandisk MP3 player(have several as back ups) $300 which will take a micro SD card for lots of space and has gapless playback(and custom EQ) so no silence between tracks. The programming is done with the computer...getting the station Id's, jingles and playlist to the audio source so you can say a computer is also an expense.

Then it just runs itself and I get around the downtime needed for recharging by rigging the MP3 player to work on regular C batteries which gives me 3 weeks runtime continuous and 10 seconds for battery change.

Any hobby, unless you collect sea shells or something costs some money.

I have no need for expensive mixers because I'm not live and not doing many things at once. Even my voice tracks are pre-recorded. Now, there's no operating expense.

 

Mark

You can do the compressor

You can do the compressor limiting through computer software. In the case with my station that's exactly what happens. I would like to be able to have all the separates like I used to have but for right now that's exactly how I run my station. At least with nextkast it does have the separate transmitter option so that you can stream and monitor what your streaming and also make previews of tracks before you air them. In a sense nextkast was really meant for part 15 or what have you along with online streaming.

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

http://thelegacy.shorturl.com

More Power for Hobby Broadcasters

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

Just an UPDATE-not much though

Since this thread is about The SpitFire, I figure I'll throw an update in...

I found out my day signal reaches 5 houses down! With an untuned wire! Ungrounded! The person said they LOVE the Oldies on AM! That surprised me. He must have an AM antenna of some sort. He might be a DXer, and that's how he found me. Dunno.

So, tuned stick and mounted outdoors with a coil, The SpitFire COULD be a contender! I do like how Oldies sound on this thing. I see on HB's site, they are screaming about SSTRAN being either slow, or non-delivery...

Check eBay for the SpitFire under AM transmitters.

Doug

Awesome Dugger!

Awesome Dugger!

SSTran does seem MIA, not sure whats going on. Kind of a shame since the SSTran products are pretty slick.

Ah! I have The Answer

Read the text in red:

http://www.ontheair3.com/

The old guy is swamped! LOL! He got more business than he bargained for! Sometimes you have to be careful for what you wish...

Doug

That site is actually not

That site is actually not owned by SSTran in any way, its run by Pat Ryan who builds them as a side gig to his retirement. At least Pat was nice enough to put a message up.

Pat Ryan

Ah! Thanks Mighty! OK, that means Old Phil B may not be doing too well. Or HE is swamped! The Antique Radio guys are not happy with him. I got my SSTRAN after a month or so. No explanation. It just arrived.

Doug

Reply to #52

Great you are getting unexpected listeners!

Most people don't sit with a radio surfing the dial to see what they can find.

Wonder of I have any listeners the same way.

 

Mark

Most people don't sit with a radio surfing the dial

Especially on AM. Word of mouth is my next guess. The neighbors across in a small cul-de-sac were quite vocal about a radio station on their street! Playing Oldies! So there is that. The three neighbors in my building listen regularly. 

I guess there are quite a few DXers in Maine. Primarily FM I imagine. But, a few AMers as well.

Doug

Just Wondering...

Has anyone else ordered/received a SpitFire? I'm curious about your experience...

Doug

Reply to #42

I have a ground rod about 7 feet from the transmitter/antenna but the cable company is hooked to that and i get a bad hum when the SSTran is connected to that ground.

Sounds like Ac hum and not a ground loop, hard to explain.
Of course with all the trouble i have had lately with the cable company and their less than stellar internet service, i am hesitant to attach to that ground rod anyway.

I should have gone with my original plans and install the whole system next to the tool shed, it stays damp there and there is  a natural ground with the well right in front of the shed. I have had the cover off of that well and it runs pretty deep but that really doesn't offer an earth ground.

Looks like next warm spell I will be driving a rod in the ground where it stays damp and moving everything there.

Thanks

Barry of BBR 1620

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

Reply to #34

"Our station is a staion with no format.  We don't fit the commercial boys idea of a pigeon-holed top 40, classical or hip-hop station."

Mram,

Come to think of it, many of the high schools stations in Southern Ohio were open format and did have listeners. Some of those listeners were pround parents, others were die hard Alumni who love their school station.

Scarlet Oaks Voc. School WJVS-FM (D) was more of a top 40 station spinning 45's, not sure we had many listeners besides the ladies in the office upstairs, i played classic rock after school for an hour and half before we signed off the station and turned the frequency over to WAIF-FM.

My high school, Clermont Northestern had a station for several years that shared a frequency with WOBO-FM Batavia Ohio. That format was all over the place, i didn't get involved with WCNE-FM but was later on WOBO-FM as a volunteer DJ.

As i said, not many high school stations left in the Greater Cincinnati Area which is a shame.
Down here there are few student run stations, even one on AM with a few thousand watts.


Barry of BBR 1620


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

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