Fan constantly running

Is the grounding cable attached to a real ground connection?

The Dell Inspiron 1501 has a set of internal speakers but doesn't have a built-in microphone. You need to plug an external microphone into the microphone jack on the right side of the notebook as shown below. You can open Messenger and click on the Tools tab then select Audio and video setup. (note as there is no built-in webcam, it will just be an audio setup). You may decide later to add a USB webcam with a built-in microphone in which case the plug-in external microphone will no longer be required.

Get a much longer USB cable and distance yourself and the mic from the computer.
You could also try putting some soft services near the computer so that the noise doesn't travel.

Unlike 'Dynamic' microphones all condenser microphones require some sort of power supply to make them work. Sometimes this can be by way of an internal battery but many of them work on an external 'phantom' power supply.
I am not familiar with the exact model number you quote but AT make 2 types of AT2020 condenser microphone.
1) If your AT microphone is fitted with a USB plug then you can connect it directly to the USB socket on your computer, which will provide it with the power that it needs to make it work. The USB bus should automatically recognise the microphone and allocate an audio channel to it but you may still have to select this device as your input source in your recording program. How you do this will differ from one program to another.

2) However if the microphone is fitted with a standard jack-plug then it will not work by you just plugging it into your computer microphone input socket as this is not powered. You will need a separate 48volt DC power supply to power the microphone.
You will almost certainly also need some sort of microphone pre-amplifier to match the output voltage and impedance (electrical resistance) of the microphone to the levels required by your audio input socket on your computer.
Probably the best way to achieve both of these requirements at lowest cost would be to purchase a small audio mixer with a phantom power option such as the Phonic AM220 http://cpc.farnell.com/phonic/am220/mixing-console-am220/dp/DP29303

WARNING - most audio mixers only have one on/off switch for phantom, power - thus the power is either on or off for ALL channels. Some other devices - like radio microphones, keyboards and electric guitars may be damaged by having 48v dc current supplied to them

Here is a link to the technical specs sheet for the AT2020 http://www.audio-technica.com/cms/resource_library/literature/49f63e6efc082082/at2020_english.pdf
More information is available here http://www.dolphinmusic.co.uk/article/40-why-do-i-need-a-microphone-preamp-.html

This is a common problem with recording multi-track sounds on a computer. It is caused by something that is known as 'latency' - basically it is down to the fact that the signal from your microphone takes a different route through the system to that taken by the audio playback. The AT2020 is a USB microphone and the signal therefore has to pass through the USB bus circuit of your computer. Despite claims of multi-tasking your computer cannot do everything at once so it naturally creates delays to make itself work properly. This will be more of a problem with a computer which has a 'cut-down' processor such as a Celeron (Intel) or Duron/Sempron (AMD). These processors are really only intended for basic computing (office type) use and are not really up to the high demands of video or audio recordings.
You may get some improvement by tweaking some of the audio settings for your sound-card to change the hardware acceleration.
This article may help you http://www.pcmus.com/latency.htm
If you are using a dedicated midi /music recording program such as Cubase then you may be able to correct the time lag using the 'quantise' function after recording your vocals. However the best solution is likely to be a hardware one Either buy a proper multi-track mixer/recorder designed for the purpose or get a second USB microphone - play your backing track on an external device - using one microphone to capture your voice and one to re-record the backing track (the only downside for this second option will be a gradual degrading of the sound quality each time it is re-cycled)

Tascam-us100 interface doesn't have phantom power; condensor mics need phantom power to operate

i hav just bought a at2020 mic and i tried recording bought it's not workin for my dell inspiron i forgot the model anyway it's running on windows 7 so please help me out am screwed with this ****

Audio Technica is generally a good brand name in microphones, but sometimes if you talk to musicians they tend to favor names they are familiar with like Sure. In the church, school, venue world, audio technica is respected. I work audio in three separate venues and we have no trouble with our audio technica microphones.

Have you adjusted the channels--and have you tried to do so manually? Have plugged the working one into the same inputs the nonworking ones were plugged into? I know it sounds like a simple thing to ask, but sometimes the connections to the sound board are the issue. If you have the more advanced receiver for the freeway 700, there are other adjustments designed to allow you to adjust between guitar and voice. If it is preset to guitar it will not sound good for voice. You may have to change that. I am assuming you put in new batteries, but ifyou have not, you may want to try that as wireless mics use up batteries quickly.

Those are a few possibilities. If it is the actual unit, then you can look inside and see if something is loose, but as far as repair, that gets into a whole issue. Hopefully something above helps solve the problem

Pins 2&3 are the correct ones to use for checking the voice coil. Pin 1 is chassis ground and should always read infinite resistance to the other two.

That microphone has an impedance of 100 ohms, so if you are reading 30 ohms you clearly have a problem with the voice coil.

Good Luck
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