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Maybe it is BS; I don't know. I can understand why there is a need to find out why it has too much noise and seek a remedy for it. If these shops are selling snake oil, would also be interested in knowing that too.

As MS said, jacking up the VCO voltage can make the RX more sensitive and noisier too. Seen that with some Cobra 148's. But this can also cause the PLL to go out of lock if it is raised too high - too.

The 2950 I aligned/own has all of the alignment values set to stock, except for a small upward tweak on both the AM modulation and SSB/ALC. Even at stock VCO voltage, it still has a nasty receive compared to a Uniden chassis radio. The TX is all fine 'n dandy; just the receive is subpar.

Put it on a HP 8656B freq gen and a SINAD meter and adjusted it for maximum signal with the least amount of noise. I might also point out that the total harmonic distortion reading on the SINAD meter clearly pointed out this radio is a real stinker. Not the first 2950 I have tweaked with either; they all had a less than desirable noise figure. Perhaps the audio circuit is to blame; who knows unless it can be qualified.

If a shop really wanted to find out the problem area, they would put their best tech on it with a O-scope and find the offending circuit or part(s). Then let the chips fall where they may. Of course, that someone should be skilled enough to do just that and be very handy with their scope and then see if they can find a useful remedy. If Bob's CB Shop has/hasn't done that; I have no way knowing their claim is true. Until then, I will not say that it is BS until proven one way or another . . .

<blockquote data-quote="Robb" data-source="post: 431053" data-attributes="member: 8446">Maybe it is BS; I don&#039;t know.&nbsp; I can understand why there is a need to find out why it has too much noise and seek a remedy for it.&nbsp; If these shops are selling snake oil, would also be interested in knowing that too.As MS said, jacking up the VCO voltage can make the RX more sensitive and noisier too.&nbsp; Seen that with some Cobra 148&#039;s.&nbsp; But this can also cause the PLL to go out of lock if it is raised too high - too.&nbsp; The 2950 I aligned/own has all of the alignment values set to stock, except for a small upward tweak on both the AM modulation and SSB/ALC.&nbsp; Even at stock VCO voltage, it still has a nasty receive compared to a Uniden chassis radio.&nbsp; The TX is all fine &#039;n dandy; just the receive is subpar.Put it on a HP 8656B freq gen and a SINAD meter and adjusted it for maximum signal with the least amount of noise.&nbsp; I might also point out that the total harmonic distortion reading on the SINAD meter clearly pointed out this radio is a real stinker.&nbsp; Not the first 2950 I have tweaked with either; they all had a less than desirable noise figure.&nbsp; Perhaps the audio circuit is to blame; who knows unless it can be qualified.If a shop really wanted to find out the problem area, they would put their best tech on it with a O-scope and find the offending circuit or part(s).&nbsp; Then let the chips fall where they may.&nbsp; Of course, that someone should be skilled enough to do just that and be very handy with their scope and then see if they can find a useful remedy.&nbsp; If Bob&#039;s CB Shop has/hasn&#039;t done that; I have no way knowing their claim is true.&nbsp; Until then, I will not say that it is BS until proven one way or another . . .</blockquote>

[QUOTE="Robb, post: 431053, member: 8446"] Maybe it is BS; I don't know. I can understand why there is a need to find out why it has too much noise and seek a remedy for it. If these shops are selling snake oil, would also be interested in knowing that too. As MS said, jacking up the VCO voltage can make the RX more sensitive and noisier too. Seen that with some Cobra 148's. But this can also cause the PLL to go out of lock if it is raised too high - too. The 2950 I aligned/own has all of the alignment values set to stock, except for a small upward tweak on both the AM modulation and SSB/ALC. Even at stock VCO voltage, it still has a nasty receive compared to a Uniden chassis radio. The TX is all fine 'n dandy; just the receive is subpar. Put it on a HP 8656B freq gen and a SINAD meter and adjusted it for maximum signal with the least amount of noise. I might also point out that the total harmonic distortion reading on the SINAD meter clearly pointed out this radio is a real stinker. Not the first 2950 I have tweaked with either; they all had a less than desirable noise figure. Perhaps the audio circuit is to blame; who knows unless it can be qualified. If a shop really wanted to find out the problem area, they would put their best tech on it with a O-scope and find the offending circuit or part(s). Then let the chips fall where they may. Of course, that someone should be skilled enough to do just that and be very handy with their scope and then see if they can find a useful remedy. If Bob's CB Shop has/hasn't done that; I have no way knowing their claim is true. Until then, I will not say that it is BS until proven one way or another . . . [/QUOTE]

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