Tim, regarding your comment in post #11 -
"I haven't been able to find any data on pre-emphasis for the EDM transmitters."
I just ordered the basic model EDM-LCD-CS-EP with a mono chip instead of the default stereo chip (for maximum range, given the limited field strength allowance of FM Part 15). After ordering, I began to wonder about the pre-emphasis and, rather wishing I had thought to ask the question beforehand, e-mailed them about it and received the following response,
"All units shipped to the USA get programmed with the correct 75uS pre-emphasis."
- which would explain why your unit sounded so faithful to the original program material. I know this thread is a few months old, but figured this could be useful information to anyone thinking of ordering one of these transmitters.
Very glad this thread came back to the top to remind me that after reading Tim's review I decided to order one of these transmitters.
I will have it before the end of August.
Be sure to tell us how you like it.
Mark
Will do Mark. One thing I like about this transmitter is the ability to connect an external antenna and have control over the power in order to have better control over the coverage, while staying within the Part 15 field strength limitations.
I'm thinking I could use a long length of coax to feed an outdoor antenna, placed so as to maximize outdoor coverage to nearby neighbors. Then I can dial down the power to keep the coverage to within an acceptable range. Even skinny and lossy cable such as RG174 should work, as I need less than 1mW at the antenna to stay within the Part 15 limits. Even a loss of 10 - 20dB wouldn't be a problem with up to 100mW available at the transmitter.
With the EDM transmitter it's a real challange to ge legal. In my tests, into a ten inch piece of wire, with the power switch in low, and the output adjustment turned all the way down, it was JUST BARELY legal for Part 15.
Remember, Part 15 FM legality has nothing whatsoever to do with power output, input, watts out, etc. You need a heck of a lot less than 1 mw at the antenna to be legal. The math is somwhere here on the wite, but into a typical antenna you need NANOWATTS of output power from a Part 15 transmitter to be legal.
Bill's review over at HB came up with it being illegal, period. I believe he tested with the rubber duck they offer for sale separately with your purchase. I didn't get this antenna at first, but did later order one but I don't recall having done any field strength readings with their antenna. But Bill came up with well over the limit.
They are wonderful sounding transmitters, however.
If you missed my test/review is at
http://www.ironrangecountry.com/edmreview.pdf
/p>
TIB
Yours and Bill's reviews were the two things that were most instrumental in cementing my decision to purchase it, Tim.
Certainly, it would be easy for an unwitting user to exceed the field strength limits, by being at anything other than absolute minimum power with an inefficient antenna, and this is why it's definitely a good thing to make this clear in any review.
I think the long-ish length of decidedly average coax to my outside antenna should be enough to sufficiently attenuate the signal and, if not, there's always this inline attenuator -
I owned one of these about 8 years ago. I never really was taken by it. I don't know if the design has changed significantly since then, but I found mine was really prone to hum unless I used a regulated power supply, and the signal splattered over to adjacent frequencies much more than, say, the Decade MS-100 (which, in my opinion, still reigns supreme over all Part 15/BETS-1 FM transmitters - at a cost, of course).
Now that I am ready to order an EDM FM transmitter based on Tim's great review, I am stuck by information lacking from the EDM website.
I see no mention anywhere about a power supply!
Tim said he got the recommended power supply, but I see no mention of a recommendation, price, or anything regarding a power supply.
At first I was stuck on the question of pre-emphasis, but one of our members posted his finding that all U.S. shipments are set for 75uS.
Now the question of the difference between the "BASIC" model ($151.0) and the "AUDIOPHILE" model ($234.0). It is not explained anywhere and all I can tell is that one has more parts than the other.
I am NOT getting the RDL version.
At $151, that includes the regulated power supply. It says you get:
EDM-LCD-CS-P
10/100mW PCB, Parts, Antenna,
Regulated PSU
NO ENCLOSURE
Regulated PSU is "power supply unit"
In my case "parts" equaled a power input jack I had to solder to the PC Board. That was it. Not even an IC to insert. Pretty simple "kit".
Note that this does NOT include the metal enclosure. I got the enclossure for mine, as otherwise it's just a circuit board laying on the table. The enclosure is made of VERY stout metal and a very nice piece, that lets you access all necessary controls. It does also NOT include any antenna other than their "wire test antenna" which is a hunk of wire. Good for people who don't own a hunk of wire I guess. i did break down and ordered their antenna.
I'm not certain the difference between standard and audiophile. I bought a standard and it sounds wonderful. These are well respected among the audiophile community for getting quality sound throughout a house.
I know Bill over at HB did a recent review as well, perhaps he notes the differences between the models.
But I would definitly encourage buying the unit with the enclosure.
TIB
Tim advised: "I would definitly encourage buying the unit with the enclosure."
I agree.
The price I quoted included the enclosure.
I'll check Bill's review, and if need be I'll e-mail EDM to get a sense of what the audiophile version amounts to.
I only want mono, but I'd like to know what I'm not buying.
Holy Rush Hour!
EDM answered me 1-second before I contacted them!
Well, that's the way it seemed.
Here was their reply:
Hallo Carl,
The EDM–TX-LCD model has slightly better audio distortion and signal-to-noise ratio than the CS model.
0.1 % THD vs 0.3 % THD
60 dB vs ≥ 75 dB
The output power and adjustment controls are the same between all models.
Regards, EDM Sales
This is what the hobby is all about!
It's official!
KDX has placed an order for the same exact transmitter model reviewed by Tim.
I notice that the price I quoted up above was not right... this is the amount paid:
$155.00 for Transmitter, $15.0 shipping, and $8.50 for the mono chip.
Delivery takes a projected 12-days... which will be about September 5th.
Await your report when you get it. I just hate the waiting for things don't you? Sept 5 is a long wait.
Mark
Mark says: "I just hate the waiting for things don't you? Sept 5 is a long wait."
I sort of lose my cool when I'm waiting for things.
I notice in the e-mail receipt sent to me by the EDM Sales Office they made mention of "Not Insured" because I didn't spend the extra amount for shipping insurance.
Because of that I now am going to worry that something will go wrong and the transmitter will be lost and me without insurance.
Or, the postal truck will blow over in Hurricane Harvey and the transmitter will be found in the Gulf of Mexico by refugees being deported by Trump's racist policy.
Then there's the Labor Day holiday (in the U.S.) on Monday September 4, a day when it would be nice to have the EDM.
One thing that makes the time go faster is that I'm avoiding clearing the spot where the transmitter will be installed, because being lazy requires a lot of time.
Read somewhere that EDM has a facility in California. You should email and ask about that. It could be sent from there for all you know but I don't think it's express.
Mark