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leif
2010-06-08, 14:02
I've got a set of headphones that get's radio. So all I need is a $20 fm transmitter to plug into the headphone jack of my squeezebox radio and I'll be able to listen to my squeezebox wirelessly through my headphones right? Do some fm transmitters produce better sound quality than others? Just grab any old transmitter or anyone care to reccomend one?

indifference_engine
2010-06-08, 15:19
I've got a set of headphones that get's radio. So all I need is a $20 fm transmitter to plug into the headphone jack of my squeezebox radio and I'll be able to listen to my squeezebox wirelessly through my headphones right?
Right. I have an FM transmitter attached to the line-out of my SBS server running SqueezeSlave. I use it to listen in the garden or bathroom on a cheapo FM radio. You'll probably need an in-line volume control as the headphone out might overload the transmitter (mine does).

Do some fm transmitters produce better sound quality than others? Just grab any old transmitter or anyone care to reccomend one? Don't know but I reckon range is more important than quality for this application. Also you probably want a powered one rather than battery opperated. I got a LineX one from Amazon that runs from 3 AA batteries but I adapted it to use the +5V line from a spare USB socket.

leif
2010-06-09, 01:05
[QUOTE= You'll probably need an in-line volume control as the headphone out might overload the transmitter (mine does). QUOTE]

Can you explain what is in-line volume control? And what does it mean to overload transmitter? Thanks.



Thanks for mentioning range. I want something with 30 feet range so mahap I may need something more expensive? Is transmitting through a wall going to be a problem?

I'm also using the headphone jack off of my SB radio to power my amp/speakers with a rca Y cable which sounds great but the volume output to my receiver this way is too low unfortunantly.

indifference_engine
2010-06-09, 03:25
Can you explain what is in-line volume control? And what does it mean to overload transmitter?
You see them often on mp3 player headphones, it goes inbetween the radio and the transmitter. It will prevent distortion if the headphoen output is too loud. I've got one of these <http://www.maplin.co.uk/Module.aspx?ModuleNo=33144>



I want something with 30 feet range so mahap I may need something more expensive? Is transmitting through a wall going to be a problem? I don't have problems with walls and I can get about 30 feet from it. I was pleasantly surprised by that.


I'm also using the headphone jack off of my SB radio to power my amp/speakers with a rca Y cable which sounds great but the volume output to my receiver this way is too low unfortunantly.Headphone is generally at a lower level than a "proper" line-out. Don't know much about the Radio but can the socket be switched between line and headphone? Also, if you do use an in-line volume control, put it after the splitter on the transmitter's leg.

leif
2010-06-09, 13:22
Will using a inline volume control device like the one you listed allow me to increase sound output out of the headphone jack? No the SB radio does not have a line out menu option.
Is this the FM transmitter you bought? http://www.amazon.com/LineX-Wireless-Transmitter-Audio-Adaptor/dp/B000SZAKKM

It uses one of these 7 frequencies: 106.7, 106.9, 107.1, 107.3, 107.5, 107.7, 107.9 Mhz.
How do I know these will work for me? Do I tune into them now first and make sure at least one of these stations don't come in where I am?

indifference_engine
2010-06-09, 16:35
Will using a inline volume control device like the one you listed allow me to increase sound output out of the headphone jack?No, it will only allow you to turn it down. Sounds like you might not need it.

Is this the FM transmitter you bought?
http://www.amazon.com/LineX-Wireless-Transmitter-Audio-Adaptor/dp/B000SZAKKM I think so, it looks very similar but mine has seven frequency presets ranging from 88-108; maybe that's just a regional thing?


It uses one of these 7 frequencies: 106.7, 106.9, 107.1, 107.3, 107.5, 107.7, 107.9 Mhz.
How do I know these will work for me? Do I tune into them now first and make sure at least one of these stations don't come in where I am?
Yes, as long as at least one of them is free then you can use it.

CBC_fan
2010-06-14, 21:39
I've been using a little battery-powered FM-transmitter as well. The transmitter
is connected to a splitter in the SBR's headphone jack; one side of the splitter
goes to the FM-transmitter, the other goes to a stereo RCA cable on a stereo
set.

In using an FM-transmitter, there are at least 3 issues that you're going
to have to deal with:

1) You're going to have to locate a vacant FM frequency where you live. In
urban areas, this is going to be difficult, as in most urban areas the FM
frequency band is literally saturated.

Sirius Radio has a vacant FM-frequency finder that you can use by keying in
your zip code. See: http://fmchannel.sirius.com/

For Canadians:

http://www.siriuscanada.ca/en/install/frequency.aspx

Here is another you can use:

http://lifehacker.com/231936/find-an-unused-fm-frequency-with-radio+locator

This should help you locate an unused FM channel in your area. Don't take
these results as gospel, however, you may need to experiment yourself as
well.

Ideally, the best FM-transmitter to use is one that allows you to select
a frequency in the entire FM-spectrum: i.e. from 87.9 to 107.9 MHz,
preferably in 0.1MHz increments.

2) You may have to increase the efficiency of the transmitter, by jerry-
rigging a longer aerial.

Some transmitters (like mine) have very short audio cable, which also
serves as the transmitter's antenna. Using a double female adapter and a
3.5mm (1/8") patch cord will help tremendously -- howerver, judging by the
image on Amazon's website, your audio cable is already long enough, so in
your case this step isn't necessary.

3) You can improve the receiver's efficiency at picking-up the signal.
This won't apply to your headphones, but it works nicely with any boombox
with a telescoping FM-antenna. This can be done by essentially lengthening
the antenna. I'm using a boombox with a telescoping aerial, and it's nowhere
near efficient enough at picking-up the signal from the the transmitter.

How did I lengthen the aerial? Simple. I used a daisy-chain of paperclips.

I bent one around the end of the aerial, and attached the other end to a
daisy-chain of paperclips, with the final clip attached to metal heat grate.
(You could also do the same with hookup wire and alligator clips).

For a jerry-rigged solution, it works amazingly well. Without touching the
volume knob on the boombox, the volume increased noticeably with just this one
simple step. If you're going to try this quick-and-dirty method, make sure
you're using the plain bare-metal (i.e. not plastic-coated) paperclips.

Good luck, and let us know how you make out.