• Get involved.
    We want your input!
    Apply for Membership and join the conversations about everything related to broadcasting.

    After we receive your registration, a moderator will review it. After your registration is approved, you will be permitted to post.
    If you use a disposable or false email address, your registration will be rejected.

    After your membership is approved, please take a minute to tell us a little bit about yourself.
    https://www.radiodiscussions.com/forums/introduce-yourself.1088/

    Thanks in advance and have fun!
    RadioDiscussions Administrators

Micro Power FM Transmitter Range?

D

Dxer1105

Would I get any interference complaints if I had an fm transmitter with 200 mW of power (500 ft range). It would be on a truly clear frequency (on a radio with good selectivity). The envoirnment is a residential neighborhood that is 12 miles away from antenna farm. Two strong signals are 400 khz away on an in between frequency with activity during tropo or e-skip. The fm transmitter I am talking about is the mobile black box v6000.

I just want to broadcast rock music through it and walk around with a portable shortwave to see its true range.
 
Dxer1105 said:
Would I get any interference complaints if I had an fm transmitter with 200 mW of power (500 ft range). It would be on a truly clear frequency (on a radio with good selectivity). The environment is a residential neighborhood that is 12 miles away from antenna farm. Two strong signals are 400 khz away on an in between frequency with activity during tropo or e-skip. The fm transmitter I am talking about is the mobile black box v6000.

I just want to broadcast rock music through it and walk around with a portable shortwave to see its true range.
Click to expand...

You may or may not get interference complaints, but you won't need 200 mW of power to give 500' range. That is well over the power limit for Part 15 devices. You don't want to be fined by the FCC!
 
What kind of a FM Transmitter would it be??

I have a Wireless FM Transmitter that goes like 1,000 feet on a Good Radio on 87.7
 
The fm transmitter I was looking at was the mobile black box v6000. It goes up to 200 mW of power and claims a 450' range. and it is only $109.98 when you buy it with the fm antenna.

If you are saying that 500' is achieved at 30-50 mW then what is 200 mw? 1/4 to 1/2 mile?
 
What I don't understand is there are pirate stations in the Boston area that put out a good 20 full watts of power for YEARS and never get popped by the FCC. But anyone else going even a foot over the limit - POW! Book 'em Danno.......

Your best bet is C.Crane's FM transmitter. It's under $80 and with a minor tweak can get you 200' of air......
 
Dxer1105 said:
The fm transmitter I was looking at was the mobile black box v6000. It goes up to 200 mW of power and claims a 450' range. and it is only $109.98 when you buy it with the fm antenna.

If you are saying that 500' is achieved at 30-50 mW then what is 200 mw? 1/4 to 1/2 mile?
Click to expand...

200 mW will get you about twice the distance of 50 mW. Multiply your power by 4 and you double your field strength.
 
Well the whole house fm transmitter is fcc approved and guarantees a 150' range which would cover my house with a strong signal throughout. it is $125 however, it makes those ipod fm transmitters look like trash which on average only go 15-20 feet. I will look in to the ccrane one too, even if I have to do the infamous turn of a screw to it.
 
Dxer1105 said:
The fm transmitter I was looking at was the mobile black box v6000. It goes up to 200 mW of power and claims a 450' range. and it is only $109.98 when you buy it with the fm antenna.

If you are saying that 500' is achieved at 30-50 mW then what is 200 mw? 1/4 to 1/2 mile?
Click to expand...

You don't need to spend that much on a FM Transmitter..Just buy the Wireless FM Transmitter ebay for like $5, I got lucky with my 1st one..Powerful little bugger
 
Dxer1105 said:
Well the whole house fm transmitter is fcc approved and guarantees a 150' range
Click to expand...

I have two of these and am very well satisfied. I use the one in my home to broadcast streaming audio, iTunes, etc. Pumps an awsome signal everywhere in my two-story, three bedroom house, as well as anywhere in my yard (half-acre lot). Audio quality is superb, and the signal is audible (to one extent or another) for about a half a block.

I use the second unit in the car and when I travel for pretty much the same purposes....steaming audio/iPod music from my iPhone or from my laptop in a hotel room or at the condo we stay at on the gulf coast. The unit comes with adaptors for ac, car outlet, or usb cable. It also runs forever on three AA batteries. (In my case "forever" means about a month or two in the car/hotels....or the best part of a week if I leave it on 24/7).

Small size, great signal, great sound, low maintenance, easy to use. Suffice to say it blows the doors off the stuff I've bought at Wal-Mart, Best Buy, etc.
 
I heard good things about the whole house, however I was like " damn " after the results of a modded ccrane. Someone on the internet got 700'. and with a $70 price tag that is a good deal. Thanks for your opinions, and lol on the $5 comment.
 
I just bought a C.Crane transmitter. Unmodified, it is basically useless. I can't even get a noise free signal at a distance of 10 feet on a Grundig G8. Unfortunately, I think that's what you should probably expect from a Part 15 compliant transmitter. The FCC set the field strength limits on these things so low that they are practically at the level of a spurious signal from an unintentional radiator. This was very disappointing because I need this to work for my cousin, who wants to stream a classical station from her computer to radios in her home. I've read about the infamous pot that you can tweak, but that would certainly void the certification.

I don't know how the "Whole House" transmitters can put out a signal that goes hundreds of feet and still be in compliance. My guess is that they aren't. They probably submitted one unit for testing that was adjusted to meet the FCC limit, and then they turned up the level on the production units. Because if they worked like the C.Crane, most people would return them as defective.
 
Several years ago, I bought a Ramsey FM Part-15 kit for about $130. As built, and unmodified, I can get a good, solid Stereo signal to all the radios in my house and to the neighbors on either side. It goes downhill fast any farther out, but does a very good job in the house. Ramsey had two versions of micro FM transmitter kits at the time: One was about $35 but I found this version to be very unstable, frequency-wise. The more expensive kit is very stable and can be set precisely to the frequency you want to use. These are kits and you must be able to solder, follow schematics, etc.
 
Nick said:
There are pirates that can be heard for miles that have been on the air for years. You'll be fine.
Click to expand...

OK Nick; reluctantly, I decided to tweak. I peeled back the sticker and turned up the pot. I found that the signal level went up dramatically near the maximum CW position. At full CW it transmitted at least 100' here in the lab to an ordinary table radio.

When I set up the transmitter at the intended operating location, I will adjust the level so that it is just sufficient to reach the most distant radio in the house. By doing it that way, I don't think anyone will complain. Hopefully not, anyway!
 
Thats what I had to do with my C Cranes, they are useless without the mod.
My 1st C Crane goes way farther than my 2nd one though, I guess the range varies with each unit.
 
audioguy said:
I don't know how the "Whole House" transmitters can put out a signal that goes hundreds of feet and still be in compliance. My guess is that they aren't.
Click to expand...

I've thought pretty much the same thing, but I've been running mine on a daily basis for more than three years. I operate it on a channel that's not supposed to have a useable signal here...but clearly does (it's a class A stick about 50 miles away). I can't imagine anyone squawking about my little transmitter going a couple of houses further down the street than it's supposed to, while it's seemingly o.k. for the not-so-local class A to get a few extra miles.

BTW, I have no interest whatsoever in distance. I just want a high quality signal in my home and yard. The Whole House gives me just that.
 
I will stick with a modded ccrane since I don't have much money. I was thinking of alligator clipping extra wire to the telescopic antenna too so I can further extend the range. I don't think anything would happen as long as I test the open frequencies and do a selectivity test on a cheap crap radio. On my most open frequency, I got stations 400 khz away but they are very strong and will act as cushions so it won't interfere with them. It will work. I was just gonna rebroadcast my rock music and dx test with it.
 
Status
This thread has been closed due to inactivity. You can create a new thread to discuss this topic.


Back
Top Bottom