SAM mode and beat note.

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  • Updated 4 months ago
As you know having SAM node on while in a QSO with stations off frequency causes beat note while locking onto their carrier. Is there anyway of blocking the beat note while this is in "Action"? It can get very annoying after awhile both constantly asking the station to center their frequency and the beat note zeroing tone. Can't hear anything while this is in progress too so the first part of the conversation gets lost.
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N1naz

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Posted 5 months ago

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James Del Principe

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I can appreciate what you are saying.  SAM is both a blessing and a curse.  In the not too distant past, SAM was very difficult to implement, but with the technology of the Flex, it is possible. I use it every morning on an AM roundtable. People with boat anchors are usually off from a few hundred cycles to a KC or more. In the past, this was as good as it got with analog dials and antique modulation. Receivers were broad enough so it did not make a difference. I'm not sure if there is a solution except to get everyone on frequency or just use AM and not SAM.    73, Jim
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KF4HR

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Why not create a TNF to eliminate the beat note?
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Jack WA9FVP

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SAM is very similar to AFC in an FM radio and is nothing more than a PLL system. I would think that if another station keyed up off frequency and if the frequency is within lock range of the SAM, it should obtain a fast lock. There are cases where it might take a few seconds to lock.  I found that you can increase the bandwidth a bit and widen the lock range. But be careful. If there’s a nearby carrier or SSB, SAM will phase lock to it.  
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