Signal & DC power supply using single cable

Thread Starter

pramod_bhu2k2

Joined Jun 23, 2008
7
Hi friends
This is Pramod. I want to send amplified AC signal (12 Peak to Peak) on DC 24V power supply using 300 meters cable(RG-58). This is used in case of Pre amplifier and main amplifier which is separated by 300 meters. I want to send power supply to pre amplifier and receive signal on same cable. Please help me if any body has done this.My email id is pramod@rectuson.com
 

theamber

Joined Jun 13, 2008
325
Hi friends
This is Pramod. I want to send amplified AC signal (12 Peak to Peak) on DC 24V power supply using 300 meters cable(RG-58). This is used in case of Pre amplifier and main amplifier which is separated by 300 meters. I want to send power supply to pre amplifier and receive signal on same cable. Please help me if any body has done this.My email id is pramod@rectuson.com
Can you use triax cables? what kind of signal ac and what magnitud you are trying to use? Radiated noise and crosstalk is your main concern.
 
Last edited:

beenthere

Joined Apr 20, 2004
15,819
When the signal is a large as that, not having it radiate back into your preamp will be a feat. What is the signal frequency? RG-58 is quite capacitive, and will eat signals of high frequencies.
 

SgtWookie

Joined Jul 17, 2007
22,230
You will need a signal transformer at each end to isolate the DC power and couple the signal from the cable to the amplifier. This is done in TV cable systems, but the frequency range is much higher, and the impedance is 75 Ohms, not 50 Ohms.

Impedance matching will be your big challenge at this point. You will need to do some research on finding signal transformers with that broad of a range. I think you will have to raise the lower frequency end significantly.
 

Norfindel

Joined Mar 6, 2008
326
I had never donde something like this, but don't the engineers use current loops for situations like this? Take a look at the LM10 application notes, from National. If i'm not mistaken, i think that could help you.
 
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