Vastelec Transmitter Installed!

[scottmcm]

I feel like celebrating since its the first thing I have actually finished for this year's innaugural show. Well, the show PC into which the transmitter is installed is also finished but that was easy.....

For a small bit of showing off here is my installation. Very simply I used one of the 12v supplies to power the transmitter and connected the audio inputs to the audio out connector on the mboard. This PC opens like a car hood so access is very easy and quick if I have to make any adjustments. I still need to build a proper antenna to replace the cheapo I am using now.

One question I have is that when there is no music playing the signal is totally quiet but when music plays there is a little bit of static that goes with the music. Is this due to the cheapo antenna or is there something else I should be looking at?

Thanks for all the great info!

showpc guts.jpg vastelec closeup.jpg

[Sharkey]

Pretty cool

Maybe, the static is within your computer's sound card... or maybe even because of the fact the transmitter is inside your computer, the computer may interfear with the setup... Just a prediction though

[dirknerkle]

Nice job! Did you attach it to the cover with double-stick tape?

One thing I'd check is which sound output you wired it to. If it was the one to speakers, then check your output volume -- you could be overdriving the transmitter.

If you wired it to a fixed-output audio port, it probably is overdriving the transmitter -- they often overdrive other audio inputs.

[ukewarrior]

I would look for two things:

1. sound volume too high as mentioned

2. The fact it's inside the case. The case is built to be a big RF shield, however, RF interference inside the case is fair game.

Have you tested it with the lid off?

Very nice work, very creative!

[51fordf2]

As for the above - I agree with both! If it doesn't seem to be over-driving it, you might find a metal box of some sort, to go over the transmitter, inside the case. You can probably (maybe) check if it's the RF inside the case, by taking the transmitter outside the case, if your cords will reach, and see if it makes any difference. That might tell you the direction to go.

R

[scottmcm]

Thanks for the replies all. It turns out to be option 1, overdriving volume from the source. After some playing with the sliders I found a good spot. The thing that was getting me is that the volume when using Media Player (while testing) is significantly different than when using Vixen. Now that I know that I can accomodate either. This is actually gotten me thinking about pranking my neighbor with a "new radio station" where I seem to miraculously know every next song before they play it.

Now that I am able to test with music I am noticing another thing. The output is not in stereo. Shouldn't it be? It may be the connection that I am using so I will check that out unless someone says otherwise.

Thanks all!

[scottmcm]

Almost forgot...yes, it is attached to the case with padded double back tape.

[51fordf2]

Yes, it should be stereo. You're right, check the connections - make sure your common is truly common. Plus, make sure your mp3 is stereo. I did some songs, found the same thing, then realized somehow I had set default on Audacity to mono. Had to re-do them all!

Glad you found the first problem, keep us posted on the stereo/mono question...

Roger

[scottmcm]

So it took me a week to get back to this but I got it figured out. The mboard connection I was using had a goofy pin pattern compared all of the connectors that I had to fit the slot. The common was truly not common. Then I realized it was a pre-amp output and the voltage was way too high for the transmitter so I swapped to the headphone plug and all is well now. The next step is to test antenna requirements.......

Thanks for all the help!