Anyone out there using a Whole House FM transmitter? What is your range and which model?
Determined the bare board version I purchased is indeed their version 1 model, that the FCC barked about.
The board is tiny. 1 1/4 inches x 2 1/2 inches or just over 1/3 of a business card size. Could fit 2 of these in space of one business card with a good sized gap.
Had a neighbor who is good with soldering stop by and we got leads on the board soldered. It came without such wires and the solder points are mighty small.
After a bit of fussing and cleaning up my lacking solder attempts the neighbor perfected the job. Had problems locating a 5V power source from my boxes of parts. Found a wall wart with 5V / 1A output from an old Zip drive (remember those folks?). Have to order some 3AA battery case things since they say this will run off such.
With a 3-4 inch wire antenna, the range was hideous indoors. Maybe 20 feet. A wood wall seemed to stop the signal.
Twisted a 9ft piece of solid copper wire to the 3-4 inch antenna and well, much better. Just running a sloper from the workbench to a shelf 6 inches from ceiling. Yep, guess I am out of compliance. Guess I got confused in the conversion between inches and millimeters 🙂
Testing in the basement again, so it's range dampening and limited.
Went outside and about 150ft away heading west signal faded away. Walked to my problematic south side and similar lack of signal on the FM band like I see with AM. Will be interesting to see the range when it's outdoors.
So now we have an AM and FM transmitter running for testing. Becoming the Carl Blare of self broadcasting in my neighborhood 🙂
Next goal with this FM transmitter is to get it weatherized inclusive of board, antenna, any power pieces and any audio tie-ins. Then walk it around here outdoors and temporary mount it in places and test range. Since it can easily run on battery this shouldn't be too hard. This should help determine some of the signal blocking sources and optimal placement for transmitters.
Pretty awesome little board for $14.
Looking at the Kill-a-Watt meter I have this plugged into shows 0 watts. So it's pulling a very little bit of power inclusive of that old wall wart itself.
Thinking this would be an excellent companion for a Raspberry Pi mini computer. Could fit them both in the same tiny mount. Perhaps a stacked and capped piece of PVC. One small 1 ft piece with the transmitter, computer and power pieces. Other 9-10ft piece with just the antenna wire. Both Raspberry Pi and the Whole House can run on USB / 4.5V -5V, so common power source would be simple and compact too. Would need to bundle an octopus USB hub in there and a 12V DC to 5V USB converter board (3A). All of that will fit in a 2 1/2" diameter of PVC I suspect. Then feed the system from a 12V battery that gets trickle charged via wall power (over power over ethernet) or solar.
Oh what a fun little project 🙂
Ordered 2 of the same boards myself. I soldered 2-1/4 wave lengths of wire to one of the boards per frequency. Extended them above and below the circuit and hot glued them to a piece of 1"x2" board. Connected a LM7805 regulator to it so I could operate direct from my 12 volt source.
Range still suked..
There is no certified FM transmitter that actually covers the whole house because of their dinky output, but the Wholehouse 1.0 sounds from descriptions that it might have an advantage.
Filling the whole house with FM does not violate 15.239 because the FCC is not in your house.
An FM transmitter located indoors attenuates greatly as it passes through walls to the outdoors and the signal strength on your private property has no legal significance because a) the FCC is not camped in your yard and b) there are no tent cities filled with listeners located in the yard.
But the harmonics produced by the FM transmitter need to be watched very carefully, because some of them fall inside aviation frequencies and it is vital that those harmonics be suppressed according to the rules.
If you have a VHF-TV radio tuner some of the harmonics can be monitored, and an aviation radio provides other harmonic monitoring.
I believe that it's particularly important to use a certified transmitter for FM.
There are options other than the C Crane. The Panaxis ACC100 is a good choice, and you can usually pick one up on e-bay relatively cheaply. I use a Landmark FM-350, which is certified for use both in Canada and the U.S. And of course, there's the Decade MS-100; although it's pricey, you generally get what you pay for, and sometimes they show up on e-bay for several hundred dollars.
The Ramsey FM 100B is a good choice if you don't mind assembling a kit. It features a power control so you can adjust for proper field strength and does a darn good job off it's supplied whip. Uses the BH1415 chip and produces a very clean output. A little pricey but well worth it.
I have both the FM 100B and the older brother FM 100 and the FM 100 is still working since I put it together back in 1997, never had any problems with it, or the FM 100B.
RFB
The Whole House 1.0 is FCC certified.
Like most FCC rulings, stumbling through the legalese is an epic journey in dancing and decoding.
The legal action about the transmitter seems due to Whole House importer modifying the antenna after manufacturing by lengthening it. That modification changes the unit and makes it emit above approved numbers.
As-is the importer sells the boards absent any wires probably to avoid any other compliance actions. Usually a 2-4 inch piece of lowly wire pretending to be an antenna on these.
So, while I am rogue here with my big hunk of copper, my range is limited due to environment, basement, etc.
When I take this outside, well that issue becomes somewhat moot and compliance becomes more relative.
Frankly, I don't see why the FCC should care about this board or many others. Even with a huge wire antenna, we aren't talking about much range. Hundreds of feet. It's flea power.
I can blow signals way further on 2.4Ghz with wifi and directional antennas. Have yet to see any enforcement there even though 2.4Ghz is in every smartphone, wifi, etc.
When/if the FCC comes a knocking I'll just have my lobbyist in DC do the schmoozing and tell them to knock it off and go worry about consolidating more media empires into fewer hands. We'll have Cuban cigars and a rich open bar for the politicos and a free designated driver.
"Frankly, I don't see why the FCC should care about this board or many others. Even with a huge wire antenna, we aren't talking about much range. Hundreds of feet. It's flea power."
Actually they don't. The FCC does not have a 24/7/365 roving spectrum monitor going through every neighborhood and city and town scanning for field strengths above 250uV at 3 meters...besides that, in order to check for that, they would have to be 3 meters from the signal source..which means being inside the house, or inside property lines.
They (FCC) are complaint driven. Until told about something, they have no idea it even exists.
RFB
There are as far as i know, two version's of Whole House fm transmitter.
One is made by Mobile Black Box and is adjustable from 0 mW to 200 mW while the other is by TAW Global LLC advertised to broadcast a listenable signal up to 150 feet. The WH Transmitter from TAW came in 2 versions that i know of, the 1.0 and the 2.0. I was lucky enough to win a drawing on the Whole House (TAW) Facebook page. A nice transmitter that sounds great and is now certified. The range is a little over 150 feet with the transmitter elevated something like 8 feet on a shelf inside a mobile home. I also have the other brand of Whole House Transmitter made by Mobile Black Box which has about the same range at full power and way less at 1 mW. The antenna's on both transmitters are short probably 6 inches long so the range is pitiful but compliant non the less. I think if i placed the TAW version in some PVC pipe and raise it 15 feet outside, the range would probably reach at least 900 feet.Lately it has been to cold and rainy in Kentucky to do much of anything outside. Was there another version of the Whole House that came in kit form?
http://wholehousefmtransmitter.com/
http://www.mobileblackbox.com/
Those two models @rock95seven appear to be different products. Unsure though absent FCC IDs to confirm.
The board I have is just the raw interior board from what was the TAW Whole House 1.0 transmitter. Presume that after the FCC cited and fined them, they mothballed what they had parts wise. These boards are from back then.
TAW is selling the raw boards over on Ebay.
For those interested in the Whole House 1.0 board discussed in this thread, here is the Ebay listing for the board:
http://www.ebay.com/itm/320889621717
Ahh yes the good ol BH1417 and it's very limited frequency coverage.
With a little patience and replacing that 3 position switch with an 8 position switch, you can replace that IC with the BH1415.
RFB
FCC ID: XOAWH-FMT and for Canada it’s IC.8728A-WHFMT
http://wholehousefmtransmitter.com/faqs/#question12
The Mobile Black Box V6000 isn't certified at all so beware if anyone decides they want to try one.
"The Mobile Black Box V6000 isn't certified at all so beware if anyone decides they want to try one."
Ahh that's when the good friend Mr. Attenuator comes in handy! 😀
RFB
"Ahh that's when the good friend Mr. Attenuator comes in handy! 😀 "
You are spot on RFB but i would have to suggest cracking it open and adding a small coil to the output and perhaps check the frequency output. They tend to be off frequency and are poorly matched to the metal whip antenna included in the packaging. Really not a bad transmitter if it were not for the temptation of most consumer's to crank the power up on a dipole or ground plane. It does pretty good at 10 mW. Could use a stereo generator.
"i would have to suggest cracking it open and adding a small coil to the output and perhaps check the frequency output. They tend to be off frequency and are poorly matched to the metal whip antenna included in the packaging."
I know what you mean. I've seen some pretty nasty little transmitters that have issues such as being off frequency and output a slew of harmonics.
Here is a suggestion. Take two 3-50pf trim caps and two hand wound coils made from #22 AWG insulated copper wire. Use a 1/4 inch drill to form the coils. Coils should be close wound at first. This will make a tunable low pass filter and help match up the output of the unit as well as notch out the nasty harmonics. The trim caps are installed in parallel and the coils in series and placing the first trim cap at the two coil junction connection and to ground. The second trim cap at the last coil and output junction connection to ground. This forms a very simple but effective low pass filter, and can be bandwidth adjusted by simply expanding the coil windings. You can get as much as 60db attenuation with this little filter. I used this on one of those Veronica transmitters so boasted about over at the DIY forums and warned those users of it that the thing stock outputs a fat 2nd and 3rd harmonic almost the same level as the fundamental! This little filter notched those harmonics down below 60db, and the thing actually produced better sound on the fundamental.
For the off frequency issue, I usually take a 3-30pf trim cap and connect it in parallel from ground to one of the crystal's leads, removing the fixed capacitor as well. Then adjust the crystal to bring it all on frequency.
To add stereo, you could use the old BA1404 IC and connect to the MPX output pin bypassing the IC's internal RF oscillator. HERE is a schematic for just such a puppy using the BA1404 chip.
RFB