vhf amp question

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woodro
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vhf amp question

Post by woodro »

Is it possible to use a vhf amp designed to operate between 136-175mhz for lpfm?
thanks, Woody
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pcs
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Post by pcs »

Nope
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Marko - PCS Electronics
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woodro
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Post by woodro »

could you explain Marko. I've heard of people using amps designed for 2 meter ham use but maybe they need to be tuned. I always thought that there was no real problem operating below an amps designed freq range but not above. (below within reason) I'm curious as to what the key differences are between an amp sold as a "broadband lpfm" amp and one that is made for 2 meter ham use or one thats made for 136-174. Is retuning not an option?
thanks, Woody
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Post by Rio »

woodro wrote:could you explain Marko. I've heard of people using amps designed for 2 meter ham use but maybe they need to be tuned. I always thought that there was no real problem operating below an amps designed freq range but not above. (below within reason) I'm curious as to what the key differences are between an amp sold as a "broadband lpfm" amp and one that is made for 2 meter ham use or one thats made for 136-174. Is retuning not an option?
thanks, Woody
I think the real problem if you use booster which not designed for LPFM, it is use some component values which won't work on the LPFM freq. range (88-108 MHz). For eg. coil and capacitor combination which arranged as Oscillator Tank should have correct values to work in particular frequency.
Your 2 m booster which stated work for 136-174 is also "broadband" which mean work properly on those range band with no tuning necessary. At the same term LPFM broadband work properly between 88 to 108 MHz / 3 metres band without tuning required.
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cliffyk
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Post by cliffyk »

There seems to be some part of "designed to operate between 136-175mhz" that you don't understand...

Seriously though, there are many "HAM" amps that can be re-engineered to operate in the broadcast band--some with relative ease, some with more difficlulty.

So, if your question is purely as stated in the original post, then the answer is YES (it is possible)--however if you meant "Is it possible to use a vhf amp designed to operate between 136-175mhz [(without modification)] for lpfm?" then it is as Marko said a plain and simple NO...
-cliff knight-
My Miata
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