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Chirpy audio in ubitx6.1 #bfo #ubitxv6 #v6

 

The attached is Rx audio of my ubitx v6.1. Audio is too chirpy and unpleasant to hear. But Tx audio is good as per other hams reports. I tried several bfo adjustments. Anyone help me to rectify the issue.
Rx video clip? -

VID_20250314_074817.mp4
VID_20250314_074817.mp4

 

Hello Praba,
?
Two possible mods might help:
1 - Add a 10uF capacitor across C75.? If electrolytic, the + goes to pin 1. (see 9.2.2 in the datasheet)
2 - Add the bass boost circuit described in the TI LM386 datasheet section 9.2.5.
?
?
73
Evan
AC9TU
?
?
?
 

I tried both mods.
Not much improvements in audio quality.
I observed 59++ signals doing good with little distortion. Signals below 58 are heavily distorted.
?I have some small TDA2822 and LM 1875 amp modules in my junk. If I want use them as audio amp bypassing LM386, from where I take audio input?.
?
?
 

Found a cure for this defect. I have disabled existing LM386 audio amp and used TDA2822 amp module. I took audio input from IC socket pin 3 without any surgery. Now audio is good. The only issue is slightly lower audio level and yet to find ?space for audio module inside cabinet.
 

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That’s the ham radio spirit!! Congrats !!

Gordon kx4z


On Mar 14, 2025, at 14:43, Praba Karan via groups.io <vu3dxr@...> wrote:

?
Found a cure for this defect. I have disabled existing LM386 audio amp and used TDA2822 amp module. I took audio input from IC socket pin 3 without any surgery. Now audio is good. The only issue is slightly lower audio level and yet to find ?space for audio module inside cabinet.

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