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typoagain
11-05-2010, 08:19 AM
I need a new transmitter for this year and money is tight. The wife bought me a cheap-o transmitter on Ebay and it actually works fairly well-IF I keep the volume turned all the way down on the computer.

I have it hooked up to the speaker out and It only works if I keep the volume turned all the way down. If I hook it to the line-out I get the same static all the time.

Any suggestions?

Mactayl
11-05-2010, 08:27 AM
Do have any info on the type, Brand, output specs, picture or something we can go by?

Jakeleg1969
11-05-2010, 08:35 AM
I need a new transmitter for this year and money is tight. The wife bought me a cheap-o transmitter on Ebay and it actually works fairly well-IF I keep the volume turned all the way down on the computer.

I have it hooked up to the speaker out and It only works if I keep the volume turned all the way down. If I hook it to the line-out I get the same static all the time.

Any suggestions?

If you are having to keep the volume turned all the way down, it would appear that the input to your transmitter is probably looking for an audio input at mic. level (very low) and you are feeding the transmitter line level (which is typically 30-40 db hotter). If that is the case, you will need to put a db-pad between the computer out and the transmitter in to reduce the audio level. You could also construct a variable pad using a small potentiometer (5k - 10k in size). On the three terminals on the pot. you would connect the computer output on the two outside terminals, and then connect the transmitter input to the center terminal (hot side) and the ground or shield would go to the same outside terminal as the shield coming from the computer. Then you can adjust the pot setting to whatever level you like. You can also make a fixed level pad using 3 resistors. This information is readily available on the internet.

If the input to the transmitter is indeed looking for a mic level, that would indicate some kind of an amplifier is right at the input of the transmitter and you could possibly input your computer after the mic amp, but I would not advise that unless you are really comfortable with electronics..

Jerry in Louisiana

IdunBenhad
11-05-2010, 10:19 AM
Hi:
Look at the mixer function on your computer. If there is a Speaker icon in the right side of the task bar, double click on it. The mixer should come up. Look to see if you have any function turned on that does not need to be or one of the volume controls is not at the right level.

You didn't say what computer/operating system you are using, but if you are using "onboard" audio, make sure that is the default in the system setup. Also you did not list the source of your audio. Is the audio on your harddisk or are you trying to bring it in from another source, such as CD or DVD player?

You may also have a bad cable or loose connection. There is also the possibility of a ground loop.

You need to tell us how your system is set up so it can be analyzed.

Jakeleg had very good suggestions.

Andy.wpg
11-05-2010, 07:00 PM
I have it hooked up to the speaker out and It only works if I keep the volume turned all the way down. If I hook it to the line-out I get the same static all the time.

Any suggestions?

There is a good article HERE (http://www.termpro.com/articles/faders.html). The first one is a simple way to pad speaker level to line level (line level is usually 100mV) But you could design for 30-40mV just as easily.

Hope this helps

typoagain
11-06-2010, 04:41 AM
Thanks guys for the input. I think that I can now head in the right direction.
Sadly, this is my weekend to work 3 straight 12 hour shifts, and them on Monday I have 3 appts to attend. So I can't do much till later next week. But at least now I have an idea as to just what I have to do.
I'll let you know more as I progress.

budude
11-06-2010, 11:26 AM
Well - just remember being in work is better than being out of work! Hang in there!

I use THIS (http://www.radioshack.com/product/index.jsp?productId=2102975) to adjust the level between my laptop output and the transmitter input. I think it's a better impedance match and it has much finer control than my laptop volume controls.

Jakeleg1969
11-06-2010, 03:01 PM
Well - just remember being in work is better than being out of work! Hang in there!

I use THIS (http://www.radioshack.com/product/index.jsp?productId=2102975) to adjust the level between my laptop output and the transmitter input. I think it's a better impedance match and it has much finer control than my laptop volume controls.

budude.. Kudos... best idea yet... and practical too...

Jerry in Louisiana