Limit Power

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gamevision
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Limit Power

Post by gamevision »

Is there any way to limit the output power the old Cyber Max LCD to a maximum of 1Watt?
Last edited by gamevision on Fri Dec 16, 2005 11:17 pm, edited 1 time in total.
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pcs
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Post by pcs »

To power the 150W amp or 300W amp I recommend the folowing:

1.) Run cyber max at 12V (this limits power to 3-5W)

2.) Use our atenuator to get this down to 1W. These atenuators
ship free of charge with the amps.

This is a more secure way as there is no way to accidentally up the
power above 1W.

The other way is to use potentiometer to set the power level to 1W.
But if by mistake you turn the power adjustment potentiometer, the
amplifier dies. So first version is prefered. But its your call in the end.
Best regards,
Marko - PCS Electronics
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Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
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gamevision
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Post by gamevision »

Is it possible to order the atenuator separately?

thanks
Andre`
93.3 Central FM Radio Manager
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pcs
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Post by pcs »

Nope, but you can make it yourself easily.
Best regards,
Marko - PCS Electronics
--------------------------------------------------------
Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
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gamevision
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Post by gamevision »

Can someone help me out to make this 1Watt ATTENUATOR? Would be very grateful.

Regards
Andre`
93.3 Central FM Radio Manager
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www.centralfmradio.com
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pcs
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Post by pcs »

Email me directly
Best regards,
Marko - PCS Electronics
--------------------------------------------------------
Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
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Attenuators

Post by pcs »

Image

Resistor values for a 50 ohm pi attenuator network - equal source and load
Perhaps the most common use of an attenuator is in 50 ohm radio circuits. To this end I have included a small table in figure 2 below which depicts common power reduction values of 3 db, 6 dB, 10 dB and 20 dB.

What you want here is 6dB (reduction by 4). Reduction by 2 would be
3dB. (If you want to increase your range by 100%, you usually need a boost
of signal of about 6dB, which is 4x more power).

Image
Resistor values for a 50 ohm pi attenuator network - equal source and load

For 4W to 1W, R1=150 and R2= 39. 2W resistors should handle it.

To calculate other attenuation values:
What is this "K" factor in the formula for a pi attenuator network
The factor K is called the ratio of current, voltage, or power corresponding to a given value of attenuation "A" expressed in decibels. It is the more difficult calculation which proceeds as follows:

"K" is the number 10 raised to the power of the value of attenuation "A" in dB, divided by 20.

K = 10 ("A" / 20)

As just one practical example, let's look at 3 dB attenuation and calculate our "K" factor.

K = 10 (3 dB / 20) = 10 (0.15) = 1.4125

On my calculator I entered 10 and pressed YX then entered .15

Entire explanation is here:
http://www.electronics-tutorials.com/ba ... uators.htm
Best regards,
Marko - PCS Electronics
--------------------------------------------------------
Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
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