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eBay FM Transmitter Any Good?


Arteom

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TURNING POINT!

Ladies and gentlemen of the jury, I announce the eBay FM Transmitter INNOCENT... sorta :/

Ok so I have been playing with the transmitter for a few hours, I've found out the static problem.

One, the audio jack cable it came with was bad, I used another one, and two whenever I put the new cable in I noticed if i moved it around, the transmitting sound would get worse and better. I took the unit apart, opened it, and I unsoldered the current jack and soldered another one I got from a quality broken sound card something like this: http://i.ebayimg.com...nmP!~~60_35.JPG

Afterwards, plugged everything in, crossed fingers and... SOUND! OH YEAH Less static & perhaps 90% less bleed. I adjusted the volume coming from the computer down to 25% [Per Captain Sparrows Orders AKA TJ :3] and BOOM, BANG, BING, BOB! I got VERY nice quality sound coming from all my radio's! Its not HD Bose sound, however it's quality is comparable to some of the low budget stations and even some of the higher ones on my radio! The sound actually was clear, and the static, It was basically gone. Best part, unit did not get as hot...

​THE CONTINUING PROBLEM!

Now I used the radio locator site. Found that 105.9 is the best station for me. I checked it out and the station was empty. Cool, I flipped the transmitter on, put my music onto repeat and ran to the car. Again, this was where the sound quality really surprised me. However even though it does not bleed "as bad", 106.1 Is a Hispanic/ Latino radio station, and whenever the FM Transmitter is on, the station becomes really distorted and a faint playing of my music is on, I flip it off, and the station becomes really clear again. I have not tested the range of this problem yet, but its very prominent and it worries me. Also on channel 105.3 (or something) there is a sports talk channel. Its fine and all but on channel 105.5 I can hear a mix of the sports station and my music, around 50/50 and on 105.7 I can hear my music (75% staticy and the sports 25%) Then I get to my channel and my music is playing loud and clear : )

Later on I turned of the Transmitter and realized that 105.9 started to have some country like music on it, it was extremely faint, quiet and somewhat distorted, probably from 105.1 Which is a country station, but after a white, it disappeared, and then reappeared, disappeared, reappeared, etc...? What's this supposed to mean?

In my current situation, I am afraid of getting in trouble, cause this unit still bleeds. I find it bleeds around 2 - 4 channels either way So if I tune it to 99.9 (Example) You can hear it at 99.3, 99.7, 100.1, 100.3. Sometimes it will bleed only to one station either way and randomly it will kind of JOLT and bleed around 5 stations for a few seconds....

Edited by Arteom
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I've been reading along with this thread as well, as I have yet to purchase my transmitter. As much as I'd like to, an EDM just isn't in the budget this year or probably next. So I'm going to go wtih a Chinese unit. Glad to hear you were able to resolve a lot of the issues Arteom. How far away were you when you got the bleed over? Is it possible your unit isn't sending a consistent signal strength? Could weather conditions play a factor? I have no idea, just a question...the reason I bring it up is that I live on the edge of the range of Philadelphia's news radio station on. If it's cloudy and/or dark out, I'm much more likely to pick up the signal than I am when it's clear skies or sunny.

TJ,

So ultimately, which Chinese unit would you buy if you had to go buy one now?

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When I got the bleed-over, I was parked in-front of my home, while the transmitter was in the back corner office of my house. It has to penetrate around 3 walls to get outside, And perhaps I was 150' or so away.

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Here are a few un-boxing and scale reference pictures for you guys to you know what to expect.

Sorry about quality, they we're taken on my iPad.

Small Box, but arrived in overall good condition.

9312a1bbd8c7e44f75aa27dc822dceb1.jpg

This little white box you see on top, it is completely empty, it's probably there so nothing fly's around inside, but I'm guessing it didn't work. I guess China does not have packing peanuts.

322b1622a6f8a169e63ac05309921a73.jpg

Here we see everything in the box, A instruction manual which is extremely difficult to understand, and basically pointless. Power supply is very cheap, and probably decreases the live of the transmitter because of uneven voltage, but I will change it out soon. The Audio jack cable, cheap and was broken. The antenna is really fragile and similar to the antenna style you get on small kids RC cars. The first impression of the unit is "Oh Nice" it feels solid. However note that it's blanketed with medal that will rust with even the slightest drop of water [sarcasm]. Everything on the unit moves, the inside rattles (until i glued the board down), its light, and overall it looks as if it will work. I'm not trying to convince you not to buy it, I just want you to set your expectations straight.

8a5475868920b17293efe98521e2752a.jpg

THE UNIT IS SMALL!

Yes this unit is very small, can rest on the palm of you hand easy.

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To really get a sense for size, here it is. On top is a standard sized Walmart Gift Card.

c08ae6b18ab7571d6d502de58667516d.jpg

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Artie, first, glad you found the first problem (audio cable), the second, finding an open frequency.. is there no dead channel near the bottom of the band? from 87.7 to maybe 90.9.. not many stations -want- to be at the bottom of the FM band, so look there for a clear channel.. do not use a freq near another stations. Take time and find one thats clear. daytime and nighttime. go to the bottom of the band and search there. If you have a sign already made up, well,, sorry but the cost for a new sign will still be lots less than an FCC fine. That Radio Locator is -not- any type of official "find" site.. dont use it, use your OWN car radio and search for a clear area on the band, again, down at the bottom.. bottom line, there has to be clear, unused freqs on either side of the freq you want to use (and the more clear air, the better)

Klay, I have no trouble with the CZH-05(x).. those are generally .1 to .5 (100-500milliwatt) radios, have decent audio response and good freq stability. Find one that has, at least, a way to vary the input line-level (knob). I dont recall who I got mine from, but they're pretty much al the same as far as sellers go.. Read the reviews of the specific radio if you pick one (Amazon, eBay, etc) Google the specific model number too, to see if there are any adverse user reports, fines, etc.. yeah, sounds a lil scary, but there are quite a few of these out there in the US, and even for a forum this size (and others) there havent been reports of fines being levied on those using the low-power .1-.5w transmitters. There are LOTS of reports of people using 5-10watt radios, causing all kinds of interference with nieghbors. They deserve what they get.

Condensed version, find one that will do .1watt, dont mod it in any way, find a clear freq without stations close on either side and dont think to become Howard Stern or the Greaseman with it and you'll be fine.

Edited by TJ Hvasta
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Condensed version, find one that will do .1watt, dont mod it in any way, find a clear freq without stations close on either side and dont think to become Howard Stern or the Greaseman with it and you'll be fine.

I don't know how far the .1W will get me, this .5W unit travels maybe around 4 blocks, no more.

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That's the one issue I have always wondered about myself.

What about those legal commercial stations that may be broadcasting on the OPEN FREQ in your area, but say they are 80-100+ miles away using the same freq you're using?

I know the freq I use is listed as OPEN in my area, and is the recommended freq, but there is a station that broadcasts on that same freq. in the Tampa-St Pete area that I use. And that station is over 100+ miles away from me. As a matter of fact, every open freq I have checked, all have a commercial station on them elsewhere in the state, most being between 70+ or more miles away from my location.

So I have to keep wondering myself, is there a limit on how far a commercial station can broadcast?

And if not, if they can be picked up "sporadically", and "not always", but sometimes clearly where that same freq they are on is considered an OPEN freq, that may be used by someone with an FM Transmitter, is the person using the FM Transmitter on that freq going to have any possible FCC issues? {gad that's a mouthful}.

I have asked this a few times, and still hoping to get some type of answer, because it would seem that an open frequency may be in use many miles away on a commercial station, but since we may be transmitting on that same frequency, could end up in legal troubles, even though it may be what I'd consider "out of range", but drifts in from time to time for short, and even extended durations.

Edited by Orville
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I have listed ALL the radio stations on my iPad (thank god for that voice dictation thing) and now i have tons of radio stations. I will examine each one on google, licensed radio stations in our area have websites. I will check their licence status, and continue, afterward i'll find a clump of 3 - 5 unused/ unlicensed stations, that's what ill use. It's a-lot of work. 105.9 however, gives me the clearest sound.

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So I have to keep wondering myself, is there a limit on how far a commercial station can broadcast?

Most definitely. It's specified in their license, and it can get quite detailed about which areas must receive their signals, and the limits of their coverage, usually in terms of signal strength.

And if not, if they can be picked up "sporadically", and "not always", but sometimes clearly where that same freq they are on is considered an OPEN freq, that may be used by someone with an FM Transmitter, is the person using the FM Transmitter on that freq going to have any possible FCC issues? {gad that's a mouthful}.

Part 15 of the FCC regulations, which govern unlicensed transmitters such as ours, say that, in additional to limits placed on the amount of signal we may transmit, also say that we are not allowed to interfere with any licensed station.

This means that if someone is listening to the remote station in question, then you may not interfere with their reception by transmitting on the same (or nearby) frequency. The way you could get into legal trouble is if this person who is trying to listen to the remote station complains to the FCC. That's why we pick frequencies that nobody in our neighborhoods is listening to.

Here's an easy way, if it's available, to pick a frequency (it worked for me): Find another Christmas light display in your city, and use the same frequency that they are using. Doing that has numerous advantages, one being that someone who drives to all the displays in the area can leave their radio on the same frequency.

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I wonder why AM transmitter are not popular. In my area there are a lot of open AM ch.

Maybe because no one listens to AM radio ;)

Anyways ladies and gentle men, got a station. After calling around, I seen that through the channels 107.1 - 107.9 FM only two are licensed for use, 107.1 and 107.9! How great is that :)

Later today I will try tuning the transmitter to 107.5 around the time it gets dark to see if it will interfere with the other channels, if it does, I have no other options than returning it and buying a different transmitter.

Another thing that happened today? I got my VoiceOver from the Demented elf... Everything is coming together, slowly, painfully, but positively.

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Most definitely. It's specified in their license, and it can get quite detailed about which areas must receive their signals, and the limits of their coverage, usually in terms of signal strength.

Part 15 of the FCC regulations, which govern unlicensed transmitters such as ours, say that, in additional to limits placed on the amount of signal we may transmit, also say that we are not allowed to interfere with any licensed station.

This means that if someone is listening to the remote station in question, then you may not interfere with their reception by transmitting on the same (or nearby) frequency. The way you could get into legal trouble is if this person who is trying to listen to the remote station complains to the FCC. That's why we pick frequencies that nobody in our neighborhoods is listening to.

Here's an easy way, if it's available, to pick a frequency (it worked for me): Find another Christmas light display in your city, and use the same frequency that they are using. Doing that has numerous advantages, one being that someone who drives to all the displays in the area can leave their radio on the same frequency.

There are a few that use the same freq. I do. However, since the station is a "country-western" station in question, and my neighborhood is predominatly Spanish, there probably isn't going to be anyone near me listening to that station anyway. At least not with any of my neighbors and I've talked with everyone around me to ask if they may happen to listen to that style music. Resounding answer was NO WAY! LOL

So I think I'll be good then.

Thanks for the answers Steven, I kind of figured that's what it might be, but wasn't 100% sure about it.

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Artie, first, glad you found the first problem (audio cable), the second, finding an open frequency.. is there no dead channel near the bottom of the band?

from 87.7 to maybe 90.9.. not many stations -want- to be at the bottom of the FM band, so look there for a clear channel..

< snip >

Actually those frequencies are reserved by the FCC and only licensed to Class A religious, college and PBS stations as a rule. Commercial stations cannot get a license to broadcast there in most markets.

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When using "radio-locator", remember that it is not an official FCC website. It's listings are done by volunteers and it is not always up to date. For example, it rarely lists FCC licensed low-power (LPFM) stations and Class D translators. Interfering with any of these FCC licensed stations is also a big no no.

In my town, radio-locator is still showing as GREAT (open) some freq that have had a (1) - LPFM station licensed and on air since 2009 and (2) licensed Class D translators on air since 2010. I can clearly hear these stations at my house.

Use radio-locator as a guide, but do not rely on it, as it is not always current information.

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I don't get it guys, something is playing on 107.3 FM now, earlier it was blank, it is defiantly not bleed from 107.1 or 107.9, I googled 107.3 Sacramento, nothing? Could this be someone else's transmitter or just interference?

It's horrible quality, very statics, but noticeable.

Edited by Arteom
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I don't get it guys, something is playing on 107.3 FM now, earlier it was blank, it is defiantly not bleed from 107.1 or 107.9, I googled 107.3 Sacramento, nothing? Could this be someone else's transmitter or just interference?

It's horrible quality, very statics, but noticeable.

Google or search any surrounding cities, you may find that the Freq. shows open in YOUR area, but there could be a station in the next town/city over that is a licensed station that broadcasts on that freq. Just keep listening and see if you hear any station id and call letters.

The Radio Freq guide url posted above, can help with locating the same freq used by licensed stations in towns nearby, but as others have said, it's not always completely accurate or complete. The problem is new stations can be added every day and today your freq may be open, tomorrow it may be licensed and no longer usable.

But that is how I found out that the freq I use, which is 99.7 FM is open in my area, but over 100+ miles away in another city is an active licensed country-western station on this same freq. Fortunately it doesn't always come in very clear in my area, it's on the West Coast of Florida and I'm a lot closer to the East Coast where I am. So you might want to check that locator and just see if anything is listed nearby.

But that's what I do, check out the surrounding towns within 25-50 miles {or more} and see if there is a licensed station on the freq. I'm planning on using and how well it comes in during both day and night hours.

If you can't locate one, chances may/may not be good that it might be someone nearby using an FM transmitter.

Problem is, if it does happen to be someone using an FM transmitter and is rebroadcasting a licensed radio station you wouldn't really know, but if they get caught doing that, that's just as bad as if you were broadcasting over the power limits and range the FCC sets in place. Because as much as I can recall, I do believe it is a violation of FCC rules and regulations to rebroadcast a commercial station from an unlicensed FM transmitter.

But I'm not going to back that up as 100%, but I'm sure there is someone here that knows for certain, and will hopefully chime in with the corrected information if I am in error.

Edited by Orville
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First post. Joined the forum to ask about a couple of rock bottom dirt cheap alternatives that have not been mentioned as far as I know.

http://www.ebay.com/itm/USB2-0-FM-Audio-transmitter-Wireless-adapter-/230669438036?pt=Other_MP3_Player_Accessories&hash=item35b4f84c54

http://www.ebay.com/itm/Wireless-USB-2-0-FM-Audio-transmitter-adapter-PC-/221106772176?pt=LH_DefaultDomain_0&hash=item337afd98d0

I know I'm risking some flame here, but here goes anyway. If you DO NOT have the genuine electronics bonifides to comment on modern radio-on-a-chip smd componentry then please, please, please resist the temptation to exercise your burning opinions about "getting what you pay for", "all that china stuff is junk".... ad nauseum. Some posts here meet that qualification. Too many do not.

There are plenty of valid points to be made about the general quality of chinese made components today, but in too many specific instances many higher priced "name brand" "trusted" units out there are, any more, using so many of the same basic boards, chips, components, and assembly lines that the only real difference in your overall satisfaction of the performance is better warranty and tech support per the company's reputation. And even that is a VERY big IF. (tech support for HP, Samsung, or Netgear anyone.....? Tried it lately?)

Anyway, that said, has anyone tried the above? How much coverage might one expect from adding a suitable length of straigt wire antenna pigtail onto the board?

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To start with, welcome to the madness that is LOR! There is no turning back now..

As for the links you put up.. First one... ask yourself this,

1) What range do I want

Answer. 100'-400'. Visitors should to be able to hear your show audio, full quieting from about 10 houses away, TFQ (total full quieting, means zero static/hum on an empty carrier signal). Static free (or very very close to it).

If you desire to hear the music outside of the room the transmitter is in, USB transmitters, both are flat out No. You know 5-10meters range is only 30feet? And that would be rough signal at 30' too.

If you've read the threads here, you know chinese units are reliable, cheap, and pretty much bullet-proof. total cost, usually with shipping is under $50. Do not get anything listed with a power greater than .5watts.. and nearly all will run a .1watt. That power will, reliably, give you 100'+ TFQ coverage, and staticy signal at approx 500'.

If you have the means, get the EDM-LCD-CS, or -RDS model. the -CS is abt $160, the -RDS is abt $265.

I havent used those USB wanna-be's.. but I did stay at a Holiday Inn last night.. oh, an' I'm an Extra Class ham radio operator (have been for almost 35yrs)..

Look for the CZH-05(x).. I think it's a "B" unit I've used for the last 3+ years.

Edited by TJ Hvasta
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