Re: Confused about how AGC works?

Jerry Gaffke
 

Joe,

Thanks for responding.

Can you point us to Sunil's instructions that state how to hook up his AGC board?
I clicked on "Download Manual" on his website, got an archive with a dozen files,
but could not find any description of how to wire the thing up.
Is this information available from his website?
Or is it only available from a CD that comes with the kit?

Looks like it could be a nice AGC implementation, does attenuation in one of the
IF stages to allow greater dynamic range than could be had if attenuating after the audio pre-amp.

Jerry, KE7ER


On Fri, Apr 19, 2019 at 01:43 PM, Joe Puma wrote:
Jerry I have had great success in hooking up Sunil’s AGC. I could be the poster child. I even determined a better location to grab audio instead of Vol H which is on the relay side of the R70 resistor. 
 
I do admit I had a hard time figuring things out in the beginning because of my ‘I’m still learning skillset’ but also because the CD that came with my radio kit could not be read and I only got half of the images and info off of the disk.  Then Sunil sent me some links that helped. Tuning the AGC meter was tricky but just follow the instructions again. The AGC is pretty simple. Just hook up the attenuation where Sunil stated in his instructions and you should be good to go, tune the 2kohm variable. Actually you know what.  I put a 10k because I thought it wasn’t attenuating enough I even changed one of the resistors before the AGC pot to 15kohm more then what was there. I can get specifics if anyone needs I’m going off memory.  
 
I ended up using coax for my attenuation hookup as that area is sensitive on the board and I was getting RF in from that wire as well as my IF tap for SDR. 
 

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