EDM Transmitters - Have you built one?

[oldcqr]

I'm looking for info from anyone who has built one of the EDM transmitters. Specifically I'm thinking about the EDM LCD RDS EP. I see surface mount stuff on there. Are they pre-mounted to the board, or do I have to attempt (and then ruin) it on my own?

[budude]

Unless they've changed something, the EDM "kit" consists of a 100% completed board except for the DC input jack and you need to insert a chip. I think this is some customs game as they are labeled as "parts" vs a completed assembly. It's a trivial "build" in either case. I have the older EDM-LCD (no RDS) - love it - in fact I think you'll be hard-pressed to find a single negative review on it (other than cost).

[jboyles7]

I'll confirm this -- I have 2, and LED and LCD. I LOVE them. I did feel like I was cheating on the build side of things, but it was one less thing to do last year. . .

[oldcqr]

This is all good to know. I've just about given up on getting the MiniRDS to work with my FM25B 100% so I was looking at other solutions w/rds.

I did get a Vast one from this year's group buy, so I am going to try that one next time I am in the workshop. I need to see how good the range is since I need 300' to get out to the street.

After that, it's $250 for EDM.

[IdunBenhad]

Hi:
oldcqr: You should have no problem with the Vast FM02 getting out to 300 feet. I have one on the dipole I described in "FM02 Transmitter Setup". The dipole is mounted inside a wooden building, running horizontally, and the range is easily 1/4 to 1/2 mile. The coverage in front of the display is great.

When I was playing with the antenna, I tacked it vertically in the door of the shed and the range was still out to 1/2 mile, received on a car FM receiver.

Just remember, the antenna is the answer. A lot of power is not needed if you have a good antenna.

[LabRat]

I just used "google maps" to estimate that my FM01 transmitter (when I ran it) could be picked up on my car radio, 1.2 KM (0.7 miles) away.
Significantly more than the "end of the street" that I was hoping for. This is/was in a typical suburb, with a highway and some "mixed commercial" developments in between. Had it been clear line of site, I would think another 500m at least.

View (http://maps.google.com/maps/ms?msid=204357174254368648691.0004ac6c7f4c201ccbd3 8&msa=0)

[oldcqr]

I have the same dipole antenna setup for my FM25B. It's mounted outside the workshop about 6' off the ground. Unfortunately there is a large oak tree between the workshop and the street. (You can see it here: http://www.landolights.com/main/component/option,com_ponygallery/func,detail/id,135/Itemid,62/ The tree has grown a bit in 3 years)

I'm going to be busy for the next few weekends, but as soon as I can I'll try the FM02 and see what it sounds like (and if I can get RDS working with it).

[Penfold]

With the EDM LCD RDS transmitter (I own one and love the quality) you need to watch the LCD display ribbon cables.
This creates a nasty electric hum. I believe that EDM has now placed spacers in between the board and the cable from what I've heard. Thanks to fellow DIYCers it was suggested that I use tin foil to wrap the ribbon cable then wrap the tin foil with electrical tape. Also, I put a piece of cardboard between the board and the the cable. This killed the hum.

Something to consider.

[oldcqr]

As much as I love my FM25B, I don't think I've ever been in love with the audio quality that comes out of it. It always sounds 'thin'.

[rstehle]

As much as I love my FM25B, I don't think I've ever been in love with the audio quality that comes out of it. It always sounds 'thin'.

IMO, the EDM's audio quality can't be beat by anything in it's price range (or below).

[IdunBenhad]

Hi:
One way to improve the audio quality is to run it through an external equalizer. This gives you control over the various audio frequencies and levels and helps reduce unwanted noise.

Most FM transmitters try to "shape" the audio and also limit it so the transmitter is not too "broad". If the audio is being overdriven, it is "clipped". This results in possible distortion and the filtering of some frequencies.

I "had" an equalizer/audio amp on my system, but it was stolen, along with a lot of PCMCIA cards for a laptop and I haven't replaced it yet. It did wonders for the audio, however.

[CrazyG]

Idun,

Your comment about using an equalizer jogged a thought I had last season as I was tearing down. Wonder what the resulting transmission would sound like if you equalized the whole transmission chain by feeding pink noise through the equalizer to the transmitter while monitoring the receive signal with an audio analyzer and equalizing across the pass band. You'd need a pretty good receiver to learn anything meaningful but it seems like it might be worth trying. Putting this on my list of stuff to do but the list is not getting any shorter yet...

[Jrd]

"Pink noise", what is that?

[Mactayl]

"Pink noise", what is that?

It's not as good as "Pink Floyd" but some of the sounds are there. JK:)

http://en.wikipedia.org/wiki/Pink_noise

[Reddy_Kilowatt]

There are at least a couple of software audio processors out there that can be geared toward FM transmission.

Breakaway Audio Enhancer (http://claessonedwards.com/index.php?option=com_content&view=article&id=46&Itemid=135) takes over your sound card driver and processes the computers audio output in real-time. The downside is this delays the output a bit and you may have to shift your sequence to compensate.

Another is FabulousMP3 (http://hp.vector.co.jp/authors/VA009014/page02/eng/freew_fbmp3_e.htm) while not as cool as Breakaway, it lets you do your adjustments then save it as the processed file.

-Craig

[Jrd]

It's not as good as "Pink Floyd" but some of the sounds are there. JK:)

http://en.wikipedia.org/wiki/Pink_noise

Interesting, yeah I was rocking out to Pink Floyd earlier...

[budude]

Just try to stay away from the Brown Note...

and frankly I think "Animals" was Pink Floyd's best album...

[CrazyG]

There are at least a couple of software audio processors out there that can be geared toward FM transmission.

Breakaway Audio Enhancer (http://claessonedwards.com/index.php?option=com_content&view=article&id=46&Itemid=135) takes over your sound card driver and processes the computers audio output in real-time. The downside is this delays the output a bit and you may have to shift your sequence to compensate.

Another is FabulousMP3 (http://hp.vector.co.jp/authors/VA009014/page02/eng/freew_fbmp3_e.htm) while not as cool as Breakaway, it lets you do your adjustments then save it as the processed file.

-Craig

Another possibility is JB Broadcast a VST compatible plugin. http://www.softpedia.com/get/Multimedia/Audio/Audio-Plugins/Broadcast.shtml I've used it with Audacity to pre-process files and it works fairly well.

[CrazyG]

Well I think this thread has been sufficiently hijacked. My apologies to the original poster.

[oldcqr]

Sokay. I don't mind it when things go off topic. Many times, asking a question in one area sparks great answers in another. And really, I don't consider this off topic at all. You can see how the thread progressed and how it logically came to where it is now.

[taybrynn]

I've been using breakaway and it doesn't create any perceptible delay. The sound is improved vs. straight EDM ... using FM MODE and ver. 1.30.02 Eruption setting.

[tallan]

Oldcqr,

I have the same EDM you mentioned and Love it almost as much as your recommended music site that does not yet have 2011 on it. ;-) the RDS works great with it and is not to hard to get going not to mention the sound quality.

As for the range, well lets just say after a few adjustments you will make the 300 foot quite nicely. Anyone that owns one and played with it knows that it has the power if needed. ;-)

[oldcqr]

Shhh... You didn't hear this from me, but an LPA1 works wonders (http://www.amazon.com/gp/product/B0002NRK80/ref=as_li_ss_tl?ie=UTF8&tag=laoli-20&linkCode=as2&camp=217145&creative=399369&creativeASIN=B0002NRK80). Not that I would use one -- that would be illegal. :mrgreen:

[Greg Young]

Shhh... You didn't hear this from me, but an LPA1 works wonders (http://www.amazon.com/gp/product/B0002NRK80/ref=as_li_ss_tl?ie=UTF8&tag=laoli-20&linkCode=as2&camp=217145&creative=399369&creativeASIN=B0002NRK80). Not that I would use one -- that would be illegal. :mrgreen:
Mike I can't get to the link (as it's blocked here at work), but if that is the Ramsey unit, it uses the same "high" output transistor some folks have had issues with failing.
I have the Ramsey FM100B which I have had for over a decade, and have had absolutely no issues on my end. Of course mine runs legal output.....;)