6 Meters is pretty deaf until I change preamp setting

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  • Updated 3 years ago
Occasionally when I open a panadapter and select 6 meter band, the slice on that panadapter appears pretty deaf.   I then go into the preamp or gain setting and move it from what ever it is set to (10 or 2) to something else.  As soon as I do this, the receiver starts working properly.  I set the preamp back to what it was originally, and all works fine.

Is anyone else experiencing this?
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Norm - W7CK

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Posted 3 years ago

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Photo of Norm - W7CK

Norm - W7CK

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Doesn't anyone else experience this?   Geez, I was hoping I wasn't the only one.   This leads me to believe it might be a hardware issue for me only?  I certainly hope not......
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Hi Norm, checked on my 6300 and not seeing (hearing?) that issue: setting the pre in/out has the expected effect. Is it the signal strength that changes after you toggle, or the audio you hear through speakers / DAX etc.? 
Not sure this helps at all, but the reason I ask is that I have noticed that if I set AGC to off, then the audio through DAX vanishes, but the signal strength remains constant, as you'd expect. This on CW or DIGU (JT modes)
73, Ian GM4KLN
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Norm - W7CK

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This is without using DAX.  I just load a profile and noticed that 6 meters was pretty deaf.  I started playing around and when I changed the RF Gain, the panadapter woke up.  AGC is set to MED.  My profiles all have several panadapters and slices defined.  I've only noticed this on 6m and of course on 2m which I believe was reported quite a while ago.

This has happened a few times now.
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Ken - NM9P, Elmer

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Could it be that your band persistence is leaving the preamp turned off when you switch bands?

I have found that with the new version 1.6 SSDR, the behavior is different whether you change bands via the band buttons, or by changing from a logging or contest program. The band buttons remember your preamp and agc and agc-t settings as well as antenna selection.

But using the logging program or clicking on a spot, those parameters stay the same in order to let the contesters keep a consistent behavior pattern when bouncing about the bands in a contest.

Ken - NM9P
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Tim - W4TME, Customer Experience Manager

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Are you using any third-party applications with the radio?  It is possible that these are changing the value of the preamp, but that change is not reflected on the SmartSDR slider control.
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Greg Zenger [N2GZ]

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I experience this frequently with with my 6700. I have various receive only antennas connected to RXA, RXB and XVTR These antennas have low signal levels and the preamp works well with them. Sometimes, but not always, when I switch from one antenna to the next, the radio thinks that it the preamp is on (+20dB or +30dB is displayed in the corner, and the RF Gain slider is in that corresponding position) however signals are quiet and exceptionally low (20 or 30db) as indicated on the S meter.  It turns out the radio thinks the preamp is on, but in reality its not. Switching to a different RF gain setting and then switching back fixes it.

The only third party application that I have connected is N1MM, and I have verified that this behavior is unrelated.