I was thinking, if the weather holds, I could maybe test a couple more FM transmitters.
I'm somewhat intrigued by the "C. Crane Digital FM Transmitter 2" What intrigues me, I guess, is that they advertise it as broadcasting up to 45 feet in line of sight use. But there are about a million references to a "mod" to crank up the power (it's mentioned in a ton of the Amazon reviews, there are videos on Youtube, and of course Radio Brandy has it too). Yet the HB review (granted from 2011 if I remember) stated it was right at the legal limit, but I have a list of issues with the HB test/review of this transmitter (but again, it is a 4 year old review). But it's cheap, and it would be interesting to test. And I truly hope no US Part 15 broadcasters are relying on Radio Brandy for any sort of information that is legal. That is a scary site indeed. What amuses me most is the three mile coverage promised with their Ultimate FM Broadcast Antenna. The use of which, with a certified FM transmitter makes it un-certified and puts the burden of proof for it's legal use on the user. It's clearly a gain antenna. Do these users get out their field strength meters and adjust it to the legal level? But in any event 250 uV/m at 3 meters is just that and no special antenna is going to make that amount of current go any further. That site suggests so many violations of FCC Rules and the laws of physics I'm sure it's leading many into illegal broadcasting and they don't even realize it.
Oops, little tangent there. Other than the C. Crane, I was considering one of the Ramsey units. Any votes on which Ramsey transmitter might be good to test? Don't know if there's time to build a kit before the snow files but I could give it a shot.
TIB
Tim, if I type fast maybe I'll be the first to respond.
Oh please test the C.Crame FM2! I'll even get on one knee. Wait a minute, I have to stand up, move the chair out of the way, avoid spilling a drink... oh, let's skip the kneel (no reference to Neil).
I have the FM1 and the FM2 and love them both, they both come in equally on my spectrum analyzer, but who knows what the field strengths are.
I did fiddle with the so-called power adjustment in the FM1, my take is that it's a fine tuner to edge it right onto the right power level at the factory.
The FM2 has never been opened, yet it's equal to the one I topped off.
Oh, and do the Ramsey FM 25B. It's a kit, you know. I'm just about to build my 3rd one (the other two were "borrowed" permanently by women friends).
That's my wish list.
I'd like to see what the C. Crane FM2 does. If I could get 800 Ft legally with 250 uV/M that would be good. What about that little Chinese transmitter for $5 that the dude talked about when he made the cable longer? Again could be a cheap replacement to the SainSonic AX-05B. If you test the Ramsey I'd like to see one that could be bought all together. I'm not able to put together a kit and would like to know other good FM transmitters easy on a spectrum analyzer and that know how to behave in the anti harmonics department. Its sort of why I'd like to know what mine is doing. If it can't behave on a spectrum analyzer I wonder if I can raise enough stink and get my money back? I know I had it 3 months, but still could I raise enough cain with SainSonic that they fix the harmonics (if any)?
There's the Broadcast Vision which is about $300 on their site new but can be had on ebay for much less. This is also "certified" with FCC and Industry Canada.
The Ramsey's are not certified and don't say they meet the rules in any way....I think the most interest here are the certified ones.
Mark
Hello Tim. Earlier I lobbied to encourage tests of the C.Crane FM2 and the Ramsey FM25B, however Mark has a point when he said "I think the most interest here are the certified ones."
Here's a fact. The Ramsey FM25B has a power output control and can be matched to a known certified transmitter using a radio with dBu field strength reading, spectrum analyzer, or S-meter. Nothing to gain by you spending time on it.
Therefore in solidarity with Mark and others, I change my vote to:
C.Crane FM2;
plus another certified transmitter from their list of suggestions, or your own choice.
I need a good FM Transmitter now that the Sainsonic was found to have so many harmonics that the Radio's protection circuit was tripped. More on a different thread to let everyone know.
I'd like to see the Ramsey as it can be turned Down and hopefully we could find the right amount this way to meet full 250 uV/M @ 3 meters and do a range and harmonics test on it. Yes its not certified, but since the power can be adjusted lets see if it can be tuned to meet certification. Otherwise how about the Schoche FM 4R like Carls? The C. Crane FM2?
I also would be interested in the Ccrane 2 tested with the pot adjustment for the max power and the way it comes out of the box.
Other than that and the ones you already did the only other one certified and affordable is the Broadcast Vision.
Mark
The C Crane 2 is a given. I'm curious about the range of power and what is really puts out as received, plus it's cheap.
As for the Ramsey units, I see their website states (on all their kit trnasmitters) that it's up to the user to be sure it's set up at legal power. I'm curious to see what the range might be, however. These do seem to be popular units so maybe... Plus I get the fun of putting a kit together. Be nice to build something where I don't have to go track down the parts 🙂 And besides Radio Brandy says I'm gonna get three miles with one! (with their special antenna of course)
I just looked at the Broadcast Vision website. Not a word about it being certified. At least not that I could find. I did notice however that the info under the "features" tab and the info under the "specifications" tab are identical. And it's pretty expensive for something that looks a lot like a C. Crane or a Whole House transmitter.
TIB
C Crane FM2 has been ordered for testing.
TIB
On the back label you can see the FCC and IC I'ds and certification numbers.
Can be had for a lot less on ebay but yeh, it's not much different than the wholehouse in terms of performance and features.
Mark
I'm gonna be in need of another FM TX and though my SainSonic would get me ¼ mile what good is this if there was all sorts of junk spewing out of this transmitter that can't be filtered properly to behave. I did write them in hopes they'll do the right thing even though I had it 4 months. If not I'm just out of $54 of my hard earned money. That said I want to have another transmitter with the same range. Wish I have had the money for the Whole House 3.0 that Tim sold at the time. @ 310 mW (High Power) it would have done the same as my SainSonic and I'd been happy with it as it didn't have the spurs and harmonics spewing out of it. Maybe somehow I could get the C. Crane to do the same. So if the tests are good I may buy that if he don't want it. I'd have to start to save. I can't put a kit together so the Ramsey would be my #1 choice. It has the range the TX I had in Michigan did and I do think years ago it was a Ramsey. And Yes it will do 3 miles on a Radio Shack $30 beam. However I'll be running it on a indoor antenna so at least it will do the same as my SainSonic did (Hold the Harmonics and spurs please). Tim if you get the Ramsey and it does do harmonics could you try and filter it with a 7 pole band pass filter? Please check the C. Crane for harmonics too if you do use the secret power setting for testing. Maybe it will do 100mW to 500 mW. Tell us how high and how far you got it to go. The Hole House will do 800 Ft with that wire antenna that I do know. I knew about the time it went my TX would have gone bad.
Odd that Broadcast Vision does not mention this certification on their website.
TIB
What is even more interesting is the Price!! Its in the upper $200's (Ouch). It looks like any other part 15 transmitter and even looks made of plastic. For almost $300 I'd expect something made of Metal or very hard plastic not what looks cheap to me. However if you got one at a decent price it may be interesting to see what this does. I think the C. Crane is more realistic in price not much more than that SainSonic AX-05B transmitter I had that went bad.
I highly recommend the C Crane units. I used them forever. The main one lasted 3 years running non-stop before it went out. Coverage was good, stereo seperation was fantastic, spectrally clean as well. A great feature is the LED tells you when you overmod.
The CC1 always needed to have the power tweak done when you got it however, the factory always tuned them well below the limits. Range was around 800-1000 feet in car with a 1/4 wave telescoping antenna taped on.