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Has anyone ever played with one of these vast fm transmitters before seems to be doing a pretty good job as in signal wise also has a built in software control of the transmission and rds built in just wondering even though it’s small the audio seems fine also
Total posts : 45366you really don’t want to see that unit on a spectrum analyzer. i see a possible NOUO in your future with that thing.
it’s not part 15.239 compliant and it is spectrally dirty.
just a heads up and you are living in stepped up enforcement country as well.
Total posts : 45366http://www.vastint.com/en-us/product/usb-rds-low-power-fm-transmitter-v-fmt212r
Seems to “meet” part 15 as it can be continuosly adjusted for 0-200mW output.
Any one can say meets part 15 rules but that doesn’t mean certified.
Looked and seems they don’t give a price. Wonder what the secret is?
Looks good on paper as has lots of features including on board compression and limiting.
Don’t know how legal it is as the antenna has to be directly attached to the transmitter…not by a length of coax.
They used to make another one awhile ago that was like the other Chinese transmitters that you could get on Amazon and Mobileblackbox under another name.
Never used this myself but may be good, maybe not, but find out the price and do some research first. Also look at Broadcastvision.
I ask though, if it meets part 15 rules why don’t they just have it certified for use in the USA and Canada?
Remember….you are using at your own risk.
Total posts : 45366or Decade are really the best trnamsitters going and i have personal experience with them and can attest to how good they are and they are FCC 15.239 certified. a little pricey but certified.
as always with this kind of stuff you get what you pay for.
BV / Waio as well as decades can be had on ebay much cheaper than new cost you just have to keep watch for when a bargain pops up.
Total posts : 45366Due to increased enforcement on FM, it’s wise to spend the money and get a certified transmitter.
Total posts : 45366I have the V6000 Mobile Black Box.
It is clean or at least the one i have is clean, no spurs showed up on a friend scope BUT and yes there is the dreaded BUT, it suffers from microphinics despite a poor attempt by the manufacturer to solve this problem. It is adjustable from 0 to 200 mW and contains one of those resistor type dummy loads in the rf circuitry then terminates to small female smc type connector, the antenna is electrically too short.Even at full power, this transmitter only covers at the most 1500 feet and is Mono.
I don’t know what it would do with the magnet mount antenna as I did not buy that antenna. It’s an okay transmitter but way over priced for what it is.Barry of Blue Bucket Radio 89.7 FM & 1620 AM
Edit: That transmitter fell off a desk and the case popped open, had to glue it back together, so not really made to be thrown around or handled rough.
Total posts : 45366Ya, that V6000 is the Vast older one branded with Mobileblackbox…it’s square in shape?
Mark
Total posts : 45366No, sorry, the V6000 isn’t the Vast one…..there was another but it’s gone now, forget the name.
Mark
Total posts : 45366This model of Vast transmitter is presently offered on ebay, direct from China, for $120.
It’s not certified but “Meets Part 15”. Which, of course, is impossible. To “Meet Part 15” it has to transmit a maximum of 250 uV/m at 3 meters. It states it’s adjustable from 0-200 mw. That means nothing. Is a buyer equipped to set this up and take accurate field strength readings to know if it’s set to the maximum Part 15 field strength? Since any field strength meter capable of doing this measurement costs, at minimum, about $2500 (for a used one that still needs to be calibrated) to $15,500.00 for a current model ready to go, it’s not likely someone worried about spending $120 for the transmitter is going to be equipped to set one of these up for legal operation.
If I recall, power output into a half wave dipole to meet Part 15 rules it takes about 11 NANOWATTS.
Buying this non-certified unit gives you NO indication that it’s legal. An adjustable power output does NOT “meet Part 15”. The ability to accurately set that output to the legal limit is what would makes it legal.
If you’re getting 1500 feet with an FM trasnsmitter is is NOT PART 15 LEGAL. I hate to be the bearer of bad news, but it’s a fact.
TIB
Total posts : 45366They can say “meets part 15” if it can be adjusted to the proper field strength.
But it would never get certified though. To get certified it has to be preset to the specific power out.
Decade transmitters are adjustable but comes pre-set for a certain power depending on where it’s being used(Canada or US) or for what section of the rules it will be used and if the user changes the adjustment you void the certification.
Mark
Total posts : 45366To be sold in the USA an FM Part 15 transmitter MUST be certified. It’s illegal to sell uncertified FM transmitters.
To be certified it must be tested by a certified lab (the FCC doesn’t do their own testing, generally). Certification requires not surpassing the legal field strength, having an affixed permanent antenna, or an antenna connector that is “non-standard” to make it difficult for an owner to change it, and operate only within the legal USA FM band. This misses on all three counts. There are of course other specifications that must be met, but those are three easy ones. Spectral purity is also critical.
You’re welcome to build your own non-certified FM transmitter, but you must be able to adjust the output for the legal limit, which requires an expensive field strength meter.
TIB
Total posts : 45366How then, can these Chinese transmitters, be sold in the USA by USA based sellers(Amazon and others), even under other brand names? I’m sure the FCC sees this.
Better yet how can Vast say their transmitter meets part 15 so people in the USA think it’s all OK. EDM says the same thing.
Canada’s no different in this regard either. Amazon Canada has these too.
Mark
Total posts : 45366In recent times I have read statements quoted from FCC spokesmen and opinions given by various persons regarding 15.239 which I disagree with.
I am not claiming to be right, and if I’m wrong perhaps I’ll learn eventually, but here’s what I believe is meant by 15.239.
Any FM transmitter may be used, certified or not, so long as its field strength matches that stated in 15.239 and its spurious harmonics meet 15.209.
Any antenna may be used so long as the field strength and harmonics meet 15.239 and 15.209, respectively.
Total posts : 45366Importing devices subject to FCC Equipment Authorization is not legal unless said authorization was granted by the FCC. So in terms that even I can understand, a manufactured non-certified FM transmitter regardless of of how low one can set the power is illegal.
I would have expected our Resident Hobby Agent to be all over this.
Total posts : 45366The same here(Canada). Here, even a kit you build yourself can’t be used unless approved by Industry canada.
Mark
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