Amplifier frequency operating range

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May 22, 2018
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#1
Hello all and good morning. Bought another amp, it is an fm hi-fi stereo amplifier. I was looking at the specs and one of them states that it's operating range is 88MHz to 108MHz. Not a very ideal frequency range for my scanner. I'm thinking of hooking up my scanner to it anyways.

What would the negative effects be of using the amp outside it's intended frequency operating range? Can it do any damage?
 

krokus

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#2
Hello all and good morning. Bought another amp, it is an fm hi-fi stereo amplifier. I was looking at the specs and one of them states that it's operating range is 88MHz to 108MHz. Not a very ideal frequency range for my scanner. I'm thinking of hooking up my scanner to it anyways.

What would the negative effects be of using the amp outside it's intended frequency operating range? Can it do any damage?
That frequency range is for tuning the FM broadcast band, and has nothing to do with your scanner.

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jwt873

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#4
What you have is an audio amplifier with an FM radio built in. The FM radio tunes in radio frequencies from 88 to 108 Mhz and converts them to audio frequencies. The audio frequencies put out by the tuner are connected to the amplifier when you select 'tuner' on the front of the amp.

If you look again at your specs you'll see your amplifier only works in the audio frequency range (Typically from 20 Hz to 20 kHz). It won't amplify an 88 mHz RF signal.
 
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#5
That frequency range is for tuning the FM broadcast band, and has nothing to do with your scanner.
It will have somthing to do with my scanner if I use it with it.

It will work like trying to play tennis with a fly swatter.
That bad huh? Have you tried it before? I"ll probably just try it out. If it sounds bad and doesn't amplify good then maybe I can use it with my am/fm stereo.

Anyone know how important the modulation for an amp is? Like if I tried using a fm amp on a am signal how bad would that be?

Also, what are impact sounds?
 
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#7
What you have is an audio amplifier with an FM radio built in. The FM radio tunes in radio frequencies from 88 to 108 Mhz and converts them to audio frequencies. The audio frequencies put out by the tuner are connected to the amplifier when you select 'tuner' on the front of the amp.
Whoa, mind blown. :) I had no idea. Serious.

[/QUOTE]If you look again at your specs you'll see your amplifier only works in the audio frequency range (Typically from 20 Hz to 20 kHz). It won't amplify an 88 mHz RF signal.[/QUOTE]

Forgot that 20Hz to 20Khz is the human hearing range. I'm not looking to amplify any rf signals like a pre-amp would I just want to use the amplifier for a speaker or maybe a few. With the engine noise of my truck the speakers in my scanners aren't always loud enough.

I was using a Pyle amplifier that works great but needed more amplifiers and wanted to give this Robolife USB Kentiger a try.

Maybe it's not even capable of transducing RF frequencies outside the FM broadcast band to audio frequencies then.
 
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May 22, 2018
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#9
How do you intend to "hook it up"? Would sure like to see a picture.

Why don't you tell us the make and model so we actually have a clue about what it is.
I'd hook up the scanner just out through it's headphone jack and into the aux input of the amp, think that's the only way you can hook them up, and then just connect left and right klipsh speakers to the back. Very easy.

This link might help.

https://www.amazon.com/Robolife-Ken...lifier+with+Romote+Control,without+Power+Cord
 
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#12
On, so what was the question? Something about being outside the frequency range? What's outside the frequency range? You're just trying to make the scanner louder, yes?





I'd hook up the scanner just out through it's headphone jack and into the aux input of the amp, think that's the only way you can hook them up, and then just connect left and right klipsh speakers to the back. Very easy.

This link might help.

https://www.amazon.com/Robolife-Ken...lifier+with+Romote+Control,without+Power+Cord
 
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#13
I'd hook up the scanner just out through it's headphone jack and into the aux input of the amp, think that's the only way you can hook them up, and then just connect left and right klipsh speakers to the back. Very easy.
You had us all kind of scratching our heads, especially since you posted in an antenna forum.
Yes this is an easy way to to get the scanner volume ramped up to a much higher level. If you want both left and right speakers to work you'll need an adapter like this:

https://www.amazon.com/C2G-Cables-0...&sr=1-5&keywords=mono+to+stereo+adapter+3.5mm

Anything your scanner will receive will play out the amp just fine regardless of frequency or mode of the signal.
 
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#15
On, so what was the question? Something about being outside the frequency range? What's outside the frequency range? You're just trying to make the scanner louder, yes?
Yep, I was wondering if my scanner would amplify frequencies other than than the frequency range of 88MHz to 108MHz operating range that it's states in the specs, but I realize that's just the tuning range now for the radio and not amplifying range. I get what Krokus was saying now. Yeah, just want to bump up the volume.

You had us all kind of scratching our heads, especially since you posted in an antenna forum.
Yes this is an easy way to to get the scanner volume ramped up to a much higher level. If you want both left and right speakers to work you'll need an adapter like this
I actually posted in the amateur radio equipment forum first and then they moved me to the antenna forum and then Kevin moved me to the general scanning forum here. Oh well, maybe more people will see this post now. Thanks for letting me know about the adapter, I only hooked up one speaker to my other amplifier last time ( not the amp I've been asking about) so got by without an adapter.


Anything your scanner will receive will play out the amp just fine regardless of frequency or mode of the signal
Okay, that's what I didn't know about if amplifers only work with certain frequencies or modes but apparently it doesn't matter and I wasn't understanding the meaning of that spec correctly. Looks like I'm good to go then.

Also, first time ever getting rick rolled, was waiting to see if Vagrant got anyone else. Troll. That's alright, not a listener of Astley but it was sorta relaxing music.
 
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#16
There are also amplified speakers that are designed for CB radios, scanners etc. that are in trucks and other high noise environments. They are easy to hookup. Just plug into the external speaker jack and a 12 Vdc power source like a cigarette lighter socket or wherever you get power for your radio in the vehicle.

Much simpler than what you are trying to do from what I understand.
 

KK4JUG

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#17
There are also amplified speakers that are designed for CB radios, scanners etc. that are in trucks and other high noise environments. They are easy to hookup. Just plug into the external speaker jack and a 12 Vdc power source like a cigarette lighter socket or wherever you get power for your radio in the vehicle.

Much simpler than what you are trying to do from what I understand.
I have a set of speakers with a 3.5mm plug but USB charging/power. Those might work also since most car now have several USB outlets.
 
Joined
May 22, 2018
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#18
There are also amplified speakers that are designed for CB radios, scanners etc. that are in trucks and other high noise environments. They are easy to hookup. Just plug into the external speaker jack and a 12 Vdc power source like a cigarette lighter socket or wherever you get power for your radio in the vehicle.
I have a set of speakers with a 3.5mm plug but USB charging/power. Those might work also since most car now have several USB outlets.
Think I've heard of those before but forgot they existed. Maybe I"ll have to give them a try some time.
 
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