FM transmitter

[Guest guest]

clyfe wrote:

Its not the power cord or brick. The unit powers up and the display shows the correct info. I have tried multiple audio sources with different audio cables. I know it is broadcasting because when it is on, there is no static on the channel I am broadcasting on.

Bummer. That sounds like it could be the input audio transistors (not sure I have the right part description) have gone bad, mainly because the unit is transmitting, you just aren't getting any audio in to the unit for it to get back out.

Have you also tried the Microphone input to see if that would work? As I think that may be a different set of circuits, but not entirely sure, since I don't have a schematic that would show me the wiring of the internal workings of the MBB Eclipse 4000.

If you've tried both audio input jacks, and neither works, it has to be a component that has blown somewhere in the audio input circuits.

Have no idea what it would cost, but you might be able to have it checked out to see what it would cost to be fixed at a local radio repair shop, that is, if you have one near you. They may charge a fee for looking it over, but usually they will put that fee toward the cost of repair if you have them fix it.

[Guest guest]

(I AM basing this on everything I have read in several documents concerning the legal and illegal use of unlicensed transmitters in the United States, both at Radio Ham sites, as well as FCC documents pertaining to lawsuits against such transmitters and companies.)

MBB information taken directly from their site is in RED to highlight it, my comments and understanding from reading many of the sites about this follow in black.

For those that have NOT seen or read this, I just found this information at the Mobile Black Box site:

Direct link here:

http://www.mobileblackbox.com/content/view/30/

Scroll to near the very bottom of the page.

Regulatory compliance:

MobileBlackBox.com does not advertise its products as FCC approved.
Which by everything I have read about PART 15 Certifications from the FCC, makes MBB in VIOLATION of this very important aspect!

All products are sold as experimental or hobby purposes, not for licensed broadcasting.
Doesn't matter what they claim here, they are in violation of the laws of the US and to FCC Part 15 certifications WHICH IS a requirement BEFORE any transmitter can be sold ANYWHERE in the US! MBB, is once again, in violation!

User is responsible for checking local laws/regulation and to make sure product purchased complies with particular usage. Otherwise, they should not proceed with purchase and/or return product already purchased within 30 days for a full refund, less S&H charge.
USER IS NOT responsible, Mobile Black Box is! You get busted and FCC finds the transmitteer was purchased in the US from a US company, MBB WILL BE in Hot Water due to the transmitter, once again, CAN NOT BE SOLD HERE WITHOUT FCC PART 15 CERTIFICATION!

MobileBlackBox.com or its parent company are not responsible for illegal use(s) of its products purchased by anyone.

Yet, they are selling ILLEGAL transmitters without BEING PRE-CERTIFIED by the FCC or of their (FCC) PART 15 CERTIFICATION that is a REQUIREMENT for ANY TRANSMITTER wether in KIT or PRE-ASSEMBLED FORM!

------------------------- END of MBB information --------------------------

I am beginning to think the FCC should be looking into this one too!

Now maybe I'm mistaken on MY interpretation of what I'm reading, but have serious doubt that I am, it all seemed pretty obvious and clear as I was reading and learning about the legal ramifactions of low power, unlicensed FM transmitters for sale in the United States and the FCC certifications required by any company that produces them!

-----------------------------------------------------------------------------------------------------------

In conclusion, from what I've read, I won't be recommending MBB to anyone from this point forward.

Folks don't need to borrow trouble and this, to me, spells TROUBLE!

Just my observations and opinions while really, and I do mean really, delving deep into this aspect of our hobby!

[Max-Paul]

First Orville I owe you an apology if I said anything that caused you to buy a MBB radio.

I think it was Don, but might have been another poster. I fully agree that if one used some common sense and did not try to broadcast around the world with there little FM transmitter. then more than likely they would stay off of the FCC's radar.

It's when new people show up with the old CB mind set that more power must mean people out front are going to be able to hear the audio better. So, they do the Tim Allen "arr arr arr" when they see a transmitter that will put out 10 watts and just got to have one.

All I can say is that it is in ones best interest to follow the rules/laws. Use common sense, dont get your neighbors upset with your transmitter. And have fun.

[Guest guest]

Max-Paul wrote:

First Orville I owe you an apology if I said anything that caused you to buy a MBB radio.

I think it was Don, but might have been another poster. I fully agree that if one used some common sense and did not try to broadcast around the world with there little FM transmitter. then more than likely they would stay off of the FCC's radar.

It's when new people show up with the old CB mind set that more power must mean people out front are going to be able to hear the audio better. So, they do the Tim Allen "arr arr arr" when they see a transmitter that will put out 10 watts and just got to have one.

All I can say is that it is in ones best interest to follow the rules/laws. Use common sense, dont get your neighbors upset with your transmitter. And have fun.

Hi Max-Paul, NO APOLOGIES FROM ANYONE IS NECCESSARY!

I don't blame anyone here for MY Decision of purchasing the MBB. it was mostly from reviews I had read just about everywhere over the internet that gave it such great reports. I was totally clueless as to an FM transmitter would or should have any type of FCC certification before it could even be sold in the US (and I'll bet a lot of others don't AND didn't know this either!). It was sure news to me!

I should have delved deeper back when I first started looking at getting a new transmitter. I was accustomed to buying those little cigar lighter types that work out of your car for around $15-$20 and, they, of course were FCC certified (no external antenna), but I never gave that much thought, as I figured that any transmitter would fall into that cettification. Was I wrong!

I never really saw that blurb on MBB's site until I started really reading the laws, rules and regulations recently. And it sure has opened my eyes to a lot of things I really didn't know at the time.

Again, I BLAME NO ONE for MY DECISION, after all, no one twisted my arm to purchase it, I read everything I could, and took it as it came, the majority being reviews from the MBB site and other websites, not just here at the LOR forums or PC forums (at the time) I was looking for a decent transmitter. And the PART 15 info on the FCC site didn't really address this particular issue either! So I never gave that much, if any, thought at all.

I just DIDN'T read all and what I needed to, to make a better, quality informed decision on what to buy and use. But I was naive on the better quality transmitter sets, so I bought what I thought was a "legaL" unit, which turns out, at least by what I've been reading lately, it appears is not.

Don't get me wrong, I do like the transmitter, but it does concern me that it IS NOT and HAS NOT been FCC PART 15 Certified. And MBB SHOULD have known better than to sell any of their transmitters WITHOUT having this certification in place. I tried to locate their physical address on their website (not there), but I'm pretty certain the address on my old box (if I still have it, sure I do somewhere) has their address somewhere in New Jersey if I recall correctly. So they should have known better than to sell ANY transmitter they produce without the FCC certification here in the US.

Now I'm not going to sick the FCC on them, but if someone else does over this, oh well, I'm just posting what I have found to protect others so they don't fall into, or buy a product that could possibly come back to bite them in the pocketbook! If ya know what I mean?!

As for broadcasting around the world, yes, it's nice to have good range, but NOT at the cost of ones pocketbook, freedom or both. Not to say possible confiscation of their equipment. I'd prefer a good quality signal within 50' to not more than 150' of my display, not 1/2 mile or more range. I just see no need for vast distances unless you have some really long extensions cords and are directing viewers to you display, even then I wouldn't want any great distance. I'd rather keep myself and display "out of the FCC limelight", not put it right smack in the middle of it!

So I don't want anyone feeling bad because they may have offered their advice or opinion on the MBB unit, again, it IS a very nice unit, but, that FINAL DECISION was mine and ONLY mine.

Noone here, or anywhere else, forced me to buy the MBB unit. I take full, and sole responsability for the purchases of what I may buy.

[George Simmons]

Is there a point to all of this? The topic of FM transmitters has been beaten to death here and on every other synchronized lighting forum on the planet over the past few years. Those of us who use the transmitters legally (and even those who DON'T) don't need some brown-noser beauracrat at the FCC to take on a crusade to show uncle Osama they're doing their job. Do what you want personally, but for the sake of all the rest of us, how about if you just let a sleeping dog lie?

[Guest guest]

George Simmons wrote:

Is there a point to all of this? The topic of FM transmitters has been beaten to death here and on every other synchronized lighting forum on the planet over the past few years. Those of us who use the transmitters legally (and even those who DON'T) don't need some brown-noser beauracrat at the FCC to take on a crusade to show uncle Osama they're doing their job. Do what you want personally, but for the sake of all the rest of us, how about if you just let a sleeping dog lie?

Relax George, we're hustling Orville out of of the country as we speak..they will never find him...

Oh CRAP, who is that at the door??????

If you do have a minute, baking a cake with a file might be a good backup plan...

:P:D:D

[Max-Paul]

Well George,

There is no real need for me or any of the rest of us to justify this thread to you.

But then too, there is so many threads that are basic that seem to resurface at least twice a year. So really George what is your dog in this race? All that the majority of us are trying to do is educate the new people about these radios.

So, mind your dongles George.

[THolland]

I am completely new at this and I am curious about all this because I would like to get a fm transmitter sometime in the next month or so. From what I understand here is that there is 3 popular brands EDM, MBB, and a few HLLY. Correct me if I am wrong on that part. I only want to find one that I can get a good quality sound and only need to transmit around 150 feet. any more than that would be fairly useless. About what size would be good to do this? .5, 1.0 or bigger and I know that the bigger the number the futher the signal will travel. I have been looking at a couple of the hlly because I think they are fully assembled instead of having to assemble them afterwards. Any help on this matter would be greatly appreciated.

[khawes]

Not to stir the pot.. ... but

I've got a 100mw/500mw transmitter (http://cgi.ebay.com/100mW-500mW-adjusted-output-LCD-stereo-FM-transmitter-/250679532258?pt=LH_DefaultDomain_0&hash=item3a5daa1ae2). on the 100mw setting It reaches well beyond my street, when the transmitter is indoors. (unlike the "whole house" transmitter that just reached across the street when placed out front).

Will an attenuator reduce the reach w/o affecting the clarity of the signal? and what size would be good, if I want to reduce the reach to about 300' or so.

[Guest guest]

khawes wrote:

Not to stir the pot.. ... but

I've got a 100mw/500mw transmitter (http://cgi.ebay.com/100mW-500mW-adjusted-output-LCD-stereo-FM-transmitter-/250679532258?pt=LH_DefaultDomain_0&hash=item3a5daa1ae2). on the 100mw setting It reaches well beyond my street, when the transmitter is indoors. (unlike the "whole house" transmitter that just reached across the street when placed out front).

Will an attenuator reduce the reach w/o affecting the clarity of the signal? and what size would be good, if I want to reduce the reach to about 300' or so.

10Db attenuator should work. I used one on my MBB Eclipse 4000 last year and it just barly made it past the houses on either side of me and could barely get to the street behind our house at the time, made it across the street in front of the house just fine. No loss of clarity to the audio output (transmission) at all. Just limited the range of it.

You can find one here: ($9.95 each)

http://www.mpja.com/prodinfo.asp?number=16547+TE

I believe they require a $15.00 minimum order though..

[clyfe]

Would this be just a little over the top?

http://cgi.ebay.com/Bext-T-800-750-Watt-FM-Power-Amplifier-/200605959723?pt=LH_DefaultDomain_0&hash=item2eb50c062b#ht_500wt_996

750watt FM Transmitter

[clyfe]

clyfe wrote:

Would this be just a little over the top?

http://cgi.ebay.com/Bext-T-800-750-Watt-FM-Power-Amplifier-/200605959723?pt=LH_DefaultDomain_0&hash=item2eb50c062b#ht_500wt_996

750watt FM Transmitter

Or this!!! http://cgi.ebay.com/FM-BROADCAST-TRANSMITTER-40KW-/270747878923?pt=LH_DefaultDomain_0&hash=item3f09d4c60b#ht_500wt_996

40,000 watts:D:D:D

[Jim Saul]

I'm not looking to any flames here, I'm just wondering...
Have any of you heard for Christmas Display owners getting in trouble from the FCC? What happened to them?
I did a cursory goggle search but didn't find anything.

Personally, I'm pretty safe being in a small valley and using the whole house transmitter. Even with the extra length antenna and placing the transmitter outside, you can't go more than 3 houses away without static.
In fact one of my neighbors wanted me to increase the range so he could listen to zarza radio in his house.

[Steven]

Tracy Holland wrote:

From what I understand here is that there is 3 popular brands EDM, MBB, and a few HLLY. Correct me if I am wrong on that part.

Many of us started with (and some continue to use) a Ramsey transmitter.

FM transmitters come in 3 basic categories:

1. FCC-certified transmitters. These must have built-in antennas and be very low power. Light-O-Rama sells one.
2. Kit transmitters. The manufacturer can avoid liability for these by making the end-user be the manufacturer. The Ramsey version is a PC board, case, and bag of parts. The EDM version is a mostly-assembled board that requires you to plug in an IC and solder a single power connector. I think this is "pushing" the idea of a kit, but because their transmitters are less than one Watt, transmit a clean signal, and they're located in South Africa, the FCC has not pursued them.
3. Illegal transmitters. There have been several examples posted above. In most cases, these are sold from China or elsewhere where the FCC can't go. I believe HLLY is an example.
   

[Guest guest]

I will continue to use my MBB Eclipse 4000 as well. I'll just make sure I use a "rubber ducky" antenna as opposed to the one that came with it. You can buy those rubber ducky antennas at most ANY Radio Parts store or you can find them online here:

http://www.newhamstore.com/vhf-uhf-handheld-scanner-antennas/rubber-duck-antenna-with-bnc-connector/prod_183.html

This is the EXACT same scanner antenna I am now using on my MBB Eclipse 4000 FM Transmitter, it has cut the signal distance down to less than 1/2 of 1/10th of a mile in all directions WITH NO LOSS of audio trnamission quality! No attenuator is rquired when using this antenna.

Radio Shack used to sell them in store, but could not find them on their website. So don't know if the local Radio Shacks still carry them in-store or not.


An Attenuator IS required if you use the stock antenna that comes with the MBB Eclipse 4000 as it can transmit (in my tests and experience) within a 5 mile radius under ideal weather conditions, other times, it operated about 1.5 to a 2 mile radius WITHOUT an attenuator attached, even with the attenuator (10Db), it does cut it considerably, but can still get out from 6/10ths to 1 mile radius again, under ideal weather conditions. Still over the 200' rule.

So I'll use my "rubber-ducky" scanner antenna, it works even better than the 10Db attenuator does!

[Guest guest]

do you have specs on what it is cut for?

it mentions scanner, uhf, vhf...so hard to say if it is a good match for your 88-108 mhz transmitter...their telescoping whip is spec'd at 80-280...you can hope the ducky has the same range.

while you may be getting the reduction in range you want, you may be doing it with a mismatched antenna, so not a good thing long term for your final output stage, depending on how it is designed...and from all i read, the MBB/HLLY output has a rep for being a little "dirty" to start with..

[Guest guest]

DonFL wrote:

do you have specs on what it is cut for?

it mentions scanner, uhf, vhf...so hard to say if it is a good match for your 88-108 mhz transmitter...their telescoping whip is spec'd at 80-280...you can hope the ducky has the same range.

while you may be getting the reduction in range you want, you may be doing it with a mismatched antenna, so not a good thing long term for your final output stage, depending on how it is designed...and from all i read, the MBB/HLLY output has a rep for being a little "dirty" to start with..

Don, I am ALMOST 100% positive this was the ORIGINAL style and same antenna that MBB supplied before they changed it to the "33-inch telescoping" magnet mount.

Of course they no longer sell or use that antenna on their site, but initially when I bought mine, it was an option that could have been purchased and it looked identical to the scanner antenna.

Aside from that scanners operate on both the AM and FM(wide band I believe) frequency bands, so the antenna should not be an issue, or at least from what I've read I wouldn't think so, even the local radio guy said it should work without any problems.(I sure hope he's right!)

Scanner antenna frequencies are 26.x to 899.x Mhz So FM radio stations operate on 88~108Mhz, which falls between all that, so I don't see any reason why this would cause any issues, the telescoping antenna I got with the MBB actually IMPROVES my scanners reception better than the rubber antenna. So I'd take them to be "interchangable". And at least one of the guys in a local CB repair shop told me basically the same thing. (Again, I sure hope he's right!)

We'll see. I've been letting the transmitter run on the rubber antenna now for 4 days/24 hours to see if any problems occur. So far, haven't had any problems. But I guess time will tell. I'm going to let it run for 2-3 weeks non-stop and see what happens. Like stated, been 4 days at 24 hours and still going fine.


BTW: when I bought replacement antenna (when Radio Shack sold them) for my scanners, the packaging stated UHF/VHF/FM Antenna. Another reason I believe it will work without problems.

[JBullard]

What DonFl was referring to was when the antenna is used to transmit..

Sure, for a scanner it doesn't matter, since it is only receiving, but when used as a transmitting antenna, you need to be concerned with the standing wave ratio at any given frequency.

I don't know how much of a mismatch the MBB/Hilly are rated for before the output stages are damaged.

I do know that the EDM will withstand a 20:1 SWR with no damage, according too the EDM engineers, as that is what they designed into the circuits.

[Guest guest]

JBullard wrote:

What DonFl was referring to was when the antenna is used to transmit..

Sure, for a scanner it doesn't matter, since it is only receiving, but when used as a transmitting antenna, you need to be concerned with the standing wave ratio at any given frequency.

I don't know how much of a mismatch the MBB/Hilly are rated for before the output stages are damaged.

I do know that the EDM will withstand a 20:1 SWR with no damage, according too the EDM engineers, as that is what they designed into the circuits.

Then I have no idea, or any way to even test that option. All I know is what freq's. the scanner antenna is used for. I do know when I bought it, the packaging did state UHF/VHF/FM use. But packaging has been mislabled before.

And it does look EXACTLY like the MBB antenna they used to supply with the unit before changing it. I tried to find an FM "Rubby Ducky" antenna on the net, searched in vain, couldn't find anything but UHF/VHF types.

I'm wondering if MBB initially tried using the same scanner antenna for their transmitters in the beginning before supplying them with the 33" telescoping one, which was an "option" initially.

Antenna specs can sure get confusing when there is no way to find an absolute answer, but only go on what was available initially, but MBB has removed all references to those antenna types from their site. So no way to go and look at what, if any, specs they had on the "rubber ducky" there were supplying at that time.

[Guest guest]

Orville wrote:

JBullard wrote:

What DonFl was referring to was when the antenna is used to transmit..

Sure, for a scanner it doesn't matter, since it is only receiving, but when used as a transmitting antenna, you need to be concerned with the standing wave ratio at any given frequency.

I don't know how much of a mismatch the MBB/Hilly are rated for before the output stages are damaged.

I do know that the EDM will withstand a 20:1 SWR with no damage, according too the EDM engineers, as that is what they designed into the circuits.

Then I have no idea, or any way to even test that option. All I know is what freq's. the scanner antenna is used for. I do know when I bought it, the packaging did state UHF/VHF/FM use. But packaging has been mislabled before.

And it does look EXACTLY like the MBB antenna they used to supply with the unit before changing it. I tried to find an FM "Rubby Ducky" antenna on the net, searched in vain, couldn't find anything but UHF/VHF types.

I'm wondering if MBB initially tried using the same scanner antenna for their transmitters in the beginning before supplying them with the 33" telescoping one, which was an "option" initially.

Antenna specs can sure get confusing when there is no way to find an absolute answer, but only go on what was available initially, but MBB has removed all references to those antenna types from their site. So no way to go and look at what, if any, specs they had on the "rubber ducky" there were supplying at that time.

FM may or may not be referring to operation at FM radio freqs, VHF/UHF is a wide range....hard to say. Anytime you don't see printed specs for an antenna, you can be pretty sure it is very wide band, intended for receive use only.

JBullard clarified my point..you can use a coat hanger for a receive antenna and get performance, but on the transmit side, a bad match means a lot of reflected energy, and solid state finals don't like that.

The antenna, as described, is likely designed as a very wide band all purpose receive antenna...not really made for hobby FM transmitter use.

Why not just add additional attenuation and use the antenna sent with the transmitter?