So I wanted to share my idea, and the gear I've found to maybe get a little feedback.
First of all, I want to set up and broadcast in essentially the downtown of a major US city. Is this a terrible idea, just in terms of putting my self at risk? I'm perched at a high point overlooking a large portion of a major US city, and I'd love to broadcast, but worried with that amount of potential exposure, it could be too much of a risk. Thoughts?
I was looking at these FMuser 15w transmitters (i'd see some years-old reviews on here, saying they'd had some issues, but nothing as of recent):
Are these machines reliable? Can you really get the power you want out of them? Additionally, One review mentions that the pre-emphasis is 50uS, when it should be 75uS. This is my first time researching what that means, but it seems like with a basic EQ, you could just bump up the high end to compensate? Anyway, if that transmitter isn't a good option, what is recommended?
Post by HighMountainRadio on Jan 18, 2018 18:33:11 GMT -6
Greetings Godard !
Please see my 'review' of these transmitters that are referenced in my post of today. This will give you some valuable information regarding the 'FMUser' variety as well as other 'look alikes'.. If I may be of further assistance please feel free to message me ! The Ground Plane is a good reliable antenna, as antennas go.. The one thing I would recommend, is make sure that the one you are thinking of purchasing is robust enough to tolerate your environment if you live in an area where ice and wind may be an issue ! Not all ground plane antennas are created equal from a mechanical perspective. As far as broadcasting in your desired area you would like to cover, the best advice I can offer, is keep all of your programming content as clean as a whistle, NO profanity, in music lyrics, or spoken word, and definitely refrain from any and all controversial subject matter ! There is no quicker method of getting 'noticed' than ignoring my, as well as other's advice of the same. As a matter of fact, unlicensed stations tend to be more at risk of an unwelcome visit in large metropolitan areas than if you were out in the boondocks. Additionally, do NOT maintain any 'regular' or lengthy schedule, be sporadic and don't broadcast for hours on end ! It isn't the best way to gain a decent audience but it's better than a NOUO (Notice Of Unlicensed Operation)! I'd be more than happy to offer any personal advice, technical or otherwise, so feel free to message me if you have any questions !
73... Spooky...
"Knowledge Is Always Made More Valuable By Sharing It With Others !" Always Remember To Be Kind ! True Greatness Often Has Very Humble Beginnings ! Help A Kid Out Today ! *** High Mountain Radio *** "Broadcasting From Somewhere High In The Remote Appalachian Mountains"
Post by HighMountainRadio on Jan 18, 2018 19:59:27 GMT -6
Good Evening Godard !
Yes, your idea will, in fact, work, and yes, the transmitter will come right on to the correct frequency when powered on unless there may be some specific method of powering on a particular make/model that requires a different method but from the several I have played with, they will all work in the fashion you envision.
As stated, however, in my last reply to your post, I would caution against broadcasting on a fixed schedule, it is FAR easier to be discovered by the wrong individuals by maintaining a regular schedule, especially if you broadcast for hours on end ! I also would caution against pissing anyone off in any way, it's also far easier to get a 'NOUO' by the FCC if someone complains about your station ! From the sound of it, I believe you are considering a total power output of 15 watts or less so although it is unlikely, IF by chance you cause any interference to another radio service or a cranky neighbor by being heard on their crappy cordless telephone or other similar device, I highly recommend doing all in your power to rectify the situation immediately if not sooner to keep the peace ! If you do run into just such a situation, I would be more than happy to offer easy, cheap solutions ! I recommend reading my posting with regard to: "How To Fabricate a Cheap and Effective Antenna Balun" on this forum ! An antenna balun is a mandatory item to utilize at your antenna, regardless of type used. It serves two purposes, it will keep your feedline from radiating, thus wasting valuable RF output power to the antenna, and if you don't utilize one, it will also cause you to experience a dangerously high VSWR (antenna mismatch to transmitter) which if high enough and left that way long enough can very easily destroy your transmitter's final output transistor or other type RF output device utilized in the transmitter output section ! Also, use GOOD quality coaxial cable such as RG-9913 or LMR400, it is more costly than cheap Radio Shack crap but you will be doing yourself a BIG favor by using the best grade you can afford ! Not all coaxial cables are equal in quality, durability, or signal loss ! Here, I use 1/2" 'Heliax' but that is really overkill and even more costly. The only reason I am using it is because I was lucky enough to get a few hundred feet of it for free. One parting note, never use fictitious call letters either, it's also a dead giveaway as anyone hearing the fake call letters can do a quick lookup online and realize swiftly it's a clandestine operation !
I hope that the information presented here helps you in some small way ! Feel free to post any questions or you may message me here on this forum ! Always happy to assist others !
73... Spooky...
"Knowledge Is Always Made More Valuable By Sharing It With Others !" Always Remember To Be Kind ! True Greatness Often Has Very Humble Beginnings ! Help A Kid Out Today ! *** High Mountain Radio *** "Broadcasting From Somewhere High In The Remote Appalachian Mountains"
So I wanted to share my idea, and the gear I've found to maybe get a little feedback.
First of all, I want to set up and broadcast in essentially the downtown of a major US city. Is this a terrible idea, just in terms of putting my self at risk? I'm perched at a high point overlooking a large portion of a major US city, and I'd love to broadcast, but worried with that amount of potential exposure, it could be too much of a risk. Thoughts?
I was looking at these FMuser 15w transmitters (i'd see some years-old reviews on here, saying they'd had some issues, but nothing as of recent):
Are these machines reliable? Can you really get the power you want out of them? Additionally, One review mentions that the pre-emphasis is 50uS, when it should be 75uS. This is my first time researching what that means, but it seems like with a basic EQ, you could just bump up the high end to compensate? Anyway, if that transmitter isn't a good option, what is recommended?
I'm not super familiar with antenna types. Is a ground plane the type I'd want for this sort of job?
FYI: This is a nice unit from what I have read and seen but I have not had the opportunity to evaluate one yet. You can get basically the same exact power and performance, however, by ordering a "ST-15B" Version V1, V2 or V3 Version. They can be purchased for as little as $56.00 brand new on EBay. The V2 Version offers switchable 5 or 15 watts, front panel selectable (the V1 and V3 versions are a straight 15 watts, non-adjustable) AND, even more importantly, at the time of purchase, ask the seller on Ebay or wherever you think of purchasing it from, if he can set it for 75 microsecond pre-emphasis before shipping it to you ! This is important because 75 us is the USA broadcast standard, whereas, most transmitters purchased from China or Asia come set for 50 us, the Europe and Asia standard and technically will degrade your transmitted audio. I have included a picture of a "ST-15B" for you:
73... Spooky...
Attachments:
"Knowledge Is Always Made More Valuable By Sharing It With Others !" Always Remember To Be Kind ! True Greatness Often Has Very Humble Beginnings ! Help A Kid Out Today ! *** High Mountain Radio *** "Broadcasting From Somewhere High In The Remote Appalachian Mountains"
So I wanted to share my idea, and the gear I've found to maybe get a little feedback.
First of all, I want to set up and broadcast in essentially the downtown of a major US city. Is this a terrible idea, just in terms of putting my self at risk? I'm perched at a high point overlooking a large portion of a major US city, and I'd love to broadcast, but worried with that amount of potential exposure, it could be too much of a risk. Thoughts?
I was looking at these FMuser 15w transmitters (i'd see some years-old reviews on here, saying they'd had some issues, but nothing as of recent):
Are these machines reliable? Can you really get the power you want out of them? Additionally, One review mentions that the pre-emphasis is 50uS, when it should be 75uS. This is my first time researching what that means, but it seems like with a basic EQ, you could just bump up the high end to compensate? Anyway, if that transmitter isn't a good option, what is recommended?
I'm not super familiar with antenna types. Is a ground plane the type I'd want for this sort of job?
FYI: This is a nice unit from what I have read and seen but I have not had the opportunity to evaluate one yet. You can get basically the same exact power and performance, however, by ordering a "ST-15B" Version V1, V2 or V3 Version. They can be purchased for as little as $56.00 brand new on EBay. The V2 Version offers switchable 5 or 15 watts, front panel selectable (the V1 and V3 versions are a straight 15 watts, non-adjustable) AND, even more importantly, at the time of purchase, ask the seller on Ebay or wherever you think of purchasing it from, if he can set it for 75 microsecond pre-emphasis before shipping it to you ! This is important because 75 us is the USA broadcast standard, whereas, most transmitters purchased from China or Asia come set for 50 us, the Europe and Asia standard and technically will degrade your transmitted audio. I have included a picture of a "ST-15B" for you:
73... Spooky...
Wow thank you so much for the advice! Much appreciated! I've got to say I'd never heard of an antenna balun. I will be reading your tutorial shortly.
I did have a couple questions. Your general advice, such as avoid fake call letters, avoid offensive material, etc, e.i. general pirate radio etiquette, is extremely useful and fascinating. Is there a stickied guide on this board for all things of that nature? (btw, my plan was to transmit calm instrumental music at night, so at least there would be no swearing and likely no human voices whatsoever)
Second, Do you know what sort of range I could expect with 15w? My situation is as such. I am perched about halfway up a hill in a major city. The biggest neighborhood of the city are in front of me. My expectation is that the signal won't make it very for UP the hill and certainly not OVER the hill, but looking out the other way, towards the city, where I am a few hundred feet above, well I dont know. If I we're able to find a 25W transmitter at an affordable price, would you advice stepping up to that? What are the pros and cons of running 15w vs 25w?
Post by HighMountainRadio on Jan 19, 2018 20:50:20 GMT -6
Good Evening Godard !
No problem, always happy to assist anyone here with advice, technical info, etc.. ! Well, your programming material should not garner any undue attention and I'll give you an example here of what my coverage is with 15 watts, 30 watts, 40 watts, soon to be 70 watts, I am just about finished building the 28 VDC power supply I require to supply the high power amplifier with the maximum juice to get it up to 70 watts.. I use a Ground Plane antenna with a balun here, the balun is essential to maximize your transmit output power and keeping your coaxial cable feedline from radiating, thus losing valuable RF output power to the antenna and even more importantly, presenting a dangerously high VSWR reflected back to you transmitter which even at 'low' power levels can easily cause irreversible damage to your transmitter's final output transistor or MOSFET. Even though MOSFETs tend to be more rugged you can still smoke them with high reflected power, I did, just recently. It hurts to smoke a $50.00 MOSFET ! I build most of my apparatus for the station since I am on a limited hobby budget here and I save quite a bit by scavenging parts from old discarded electronics and repurposing it for station use. I highly encourage everyone to build as much as possible since not only do you save some good $$, you gain an education, far more valuable ! Basic antennas such as a Ground Plane (GP) or J-Pole type or even Yagis are quite inexpensive to build and pretty easy to tune, even for beginners who never undertook such a project before ! I go to a local scrap/salvage yard around here and buy bright, shiny aluminum tubing lengths large enough to build these antennas for the mere cost of whatever the current 'spot price' for scrap aluminum happens to be on the day of purchase, pennies on the dollar ! I encourage you to check them out if you have any in your area ! They can be a goldmine ! I live just on the outskirts of a city of about 50,000 and I live on a slight rise above town terrain or at least right in line of sight of it's hilltop streets and with 30 watts and a Ground Plane, I cover, with ease, the majority of the town, some areas that are a bit obscured, a bit 'fuzzy' but overall pretty darn good ! I intend to increase my power to 70 watts to fill in these noisy areas better. In order to gain a 3 db increase in your signal you must double your transmit power. If you want to put a better punch into a given area, I suggest building a small 4 element Yagi antenna which is directional but you will still get enough signal off of the side to cover a decent area as well. If you need omni-directional signal coverage then a Ground Plane or J-Pole is your best bet, all antennas, no matter which type you use, should be 'vertically polarized' ! I will be experimenting with a pseudo circularly polarized antenna soon, which consists of an old 'Cross Folded Dipole' configuration mounted sideways in a 'X' configuration sloped upward at about a 45 degree angle to give me a pseudo circular polarized signal which transmits in both the horizontal as well as vertical planes to give you the best of both worlds ! More to follow after erecting it and testing.. I will post here when it is complete. It sounds like you should have no problem covering your desired area well even with 15 watts but the more 'juice' you can deliver to the antenna, the better, within reason. In most situations, I recommend at least 25 watts to minimize spotty areas of coverage. I suggest trying 15 watts and get your antenna up as high as practical, but since you are pretty high on a hill anyway you should be pretty good, but at least try to get the antenna up above any trees and structures, anything that will obscure the signal as FM broadcast is line-of-sight.. Basically, if you can see it, you can easily cover it with even 15 watts of power. I went from 10, to 15, to 30 and then to 40 without any appreciable gain in distance, but made the 'noisy' areas quite a bit less so.. Even 10 watts blasts in clear across the city at the high spots. It's a hilly town in the Appalachian Mountains. I have a fairly good line-of-sight to the majority of it. A 'balun' or 'matching transformer' is very easy to fabricate ! Be SURE to utilize one ! You can wind a seperate one or you can use the end of your feedline to wind one into the last several feet of your feedline making it an integral part of your feedline. The balun should be affixed right at the feedpoint to the antenna ! I have a 'flat' VSWR here, meaning NO reflected power because I pre-cut my antenna length to my center frequency before erecting it, I suggest you do the same. Most antennas available on EBay have a sliding element section that you can adjust for minimum reflected power. Just about EVERY ham radio operator worth his salt has an 'SWR Bridge', maybe you know someone who is a ham, but don't let the cat out of the bag as to what you are doing, 99% of hams frown on it and may 'drop the dime' on you. They are good people and more than willing to help but go 'by the book'.. You can purchase a cheap VSWR Bridge on Ebay, but before purchase, be certain that it is accurate up to at least 108 MHz. If I can be of any further assistance, please don't hesitate to ask ! Always more than happy to assist ! P.S. ... I am planning to do a 'transmitter' review on here soon, I am gathering as much data, technical and otherwise to post with pictures of each model and make that are currently available. Keep an eye out for it.. coming soon ! 73... Spooky...
"Knowledge Is Always Made More Valuable By Sharing It With Others !" Always Remember To Be Kind ! True Greatness Often Has Very Humble Beginnings ! Help A Kid Out Today ! *** High Mountain Radio *** "Broadcasting From Somewhere High In The Remote Appalachian Mountains"
