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I figured our locations would make it impractical to do your side by side testing and that's why I offered to get on 3.885. Even that probably will not work since east coast to west coast contacts their are rather difficult. Just like you I've had to add filtering after the modification because the response was from 1 cycle to nearly 100 KHz. This is no problem to do with stages that are capacitively coupled. Perhaps I can't get DC but getting the watt meter to go up and down at one cycle per second is not hard. You agree that is just as good as DC right?

The TA7222AP in the 148 GTL was designed as a stereo output chip. Surely you know it's able to reproduce Hi-Fi and the feedback loop from pin 9 (output) to pins 5 (gain adjust) and 6 (feedback) are what kills the high end. Test circuits given in the data sheet for this chip will show you how to easily configure it as an amp with flat response. Quite different from the stock circuit used in the Cobra. I'm interested in knowing what you think is going to prevent Hi-Fi modification here?

One main thing you seem to overlook is that there has never been a CB radio receiver manufactured that can reproduce lower then 200 cycles and higher then 4 KHz. Typical receiver response is 300 Hz to 3 KHz. At least on 75 meters there are receivers that can reproduce Hi-Fi. It's not very practical to think that everyone is going to modify their CB receivers to pass this bandwidth that essentially gets wasted on 11 meters.

<blockquote data-quote="Shockwave" data-source="post: 160376" data-attributes="member: 10882">I figured our locations would make it impractical to do your side by side testing and that&#039;s why I offered to get on 3.885. Even that probably will not work since east coast to west coast contacts their are rather difficult. Just like you I&#039;ve had to add filtering after the modification because the response was from 1 cycle to nearly 100 KHz. This is no problem to do with stages that are capacitively coupled. Perhaps I can&#039;t get DC but getting the watt meter to go up and down at one cycle per second is not hard. You agree that is just as good as DC right?The TA7222AP in the 148 GTL was designed as a stereo output chip. Surely you know it&#039;s able to reproduce Hi-Fi and the feedback loop from pin 9 (output) to pins 5 (gain adjust) and 6 (feedback) are what kills the high end. Test circuits given in the data sheet for this chip will show you how to easily configure it as an amp with flat response. Quite different from the stock circuit used in the Cobra. I&#039;m interested in knowing what you think is going to prevent Hi-Fi modification here?One main thing you seem to overlook is that there has never been a CB radio receiver manufactured that can reproduce lower then 200 cycles and higher then 4 KHz. Typical receiver response is 300 Hz to 3 KHz. At least on 75 meters there are receivers that can reproduce Hi-Fi. It&#039;s not very practical to think that everyone is going to modify their CB receivers to pass this bandwidth that essentially gets wasted on 11 meters.</blockquote>

[QUOTE="Shockwave, post: 160376, member: 10882"] I figured our locations would make it impractical to do your side by side testing and that's why I offered to get on 3.885. Even that probably will not work since east coast to west coast contacts their are rather difficult. Just like you I've had to add filtering after the modification because the response was from 1 cycle to nearly 100 KHz. This is no problem to do with stages that are capacitively coupled. Perhaps I can't get DC but getting the watt meter to go up and down at one cycle per second is not hard. You agree that is just as good as DC right? The TA7222AP in the 148 GTL was designed as a stereo output chip. Surely you know it's able to reproduce Hi-Fi and the feedback loop from pin 9 (output) to pins 5 (gain adjust) and 6 (feedback) are what kills the high end. Test circuits given in the data sheet for this chip will show you how to easily configure it as an amp with flat response. Quite different from the stock circuit used in the Cobra. I'm interested in knowing what you think is going to prevent Hi-Fi modification here? One main thing you seem to overlook is that there has never been a CB radio receiver manufactured that can reproduce lower then 200 cycles and higher then 4 KHz. Typical receiver response is 300 Hz to 3 KHz. At least on 75 meters there are receivers that can reproduce Hi-Fi. It's not very practical to think that everyone is going to modify their CB receivers to pass this bandwidth that essentially gets wasted on 11 meters. [/QUOTE]

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