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Ubitx - using Amateurradiokits.in AGC #ubitx

John McClun
 

I've purchased the AGC from Amateurradiokits.in and wondered if any one else has used it in their Ubitx? (not bitx20 or 40) Has it worked to provide AGC? 
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John
NQ3RP

Eddie Esserman
 

I have the kit as well, and can't figure out where to connect the IF input. Sunil says it goes to the first IF input.  Can anyone tell me where that is, what pin and component specifically that is.  I don't need a picture, but it couldn't hurt if you've got one opened up.  I'm using V3.

It should work well, but let me find the first IF input and I'll be the first to report.

Eddie
WA4JXL

Eddie Esserman
 

I'll admit, I am from the tube age, so I really need wire goes HERE type instructions.  And almost kit like mentality.  I put the radio down for decades and missed transistors, ICs, and Arduinos.

Eddie

Jon Titus, KZ1G <tituskz1g@...>
 

I find clarity and precision of instructions--if any--sadly lacking from many electronic kits and projects.  The same goes for illustrations that lack important details such as part locations, pinouts, part numbers, flow charts, etc.  Some of our good ham writers and editors might offer to help, but it's an uphill battle.

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Jon Titus, KZ1G
Herriman, UT USA

Richie Chambless
 

I’ve taken a look at this circuit, too. I think Sunil is talking about the power to the first bi-directional amplifier (receive +) before the mixer. I don’t know how well that would work, but I guess it could be worth a try. I’ve added a manual RF gain control to my Bitx using Fig. 6.42 from EMRFD. It could be connected to something like that and probably work.

Eddie Esserman
 

Thanks, Richie.  The mystery is part of the fun, and frustration.

Eddie

John McClun
 

Sunil says to wire it just like the instructions for a Bitx20.  Still a little sketchy for me.  I need a schematic !!????

--
John
NQ3RP

John McClun
 

Uploaded schematics & adjustment procedure that Sunil sent for uBitx to folders. Should help with using his AGC. 
--
John
NQ3RP

Eddie Esserman
 

John,

Where did you upload the schematics and procedure?

I've been off trail for a few days.

Eddie

Ted
 

Another solution in search of a problem to some, perhaps, though here's another take on AGC that also provides extra RX gain in one.  It seems to work well so far.

Wayne Leake
 

 here is a partial schematic for the BITX40 from amateurradiokits.in.
 You can see where the AGC ic connected to the first RX IF amp.


image.png


I'll look for the schematic for the AGC kit for the same, at least theone I have parts for.

Wayne Leake
 

 Here is the scematic.

image.png

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Wayne Leake
 

 Also, I forgot, here is the board layout for the board that comes with the kit.
 I inly have the parts, but will put them on a perfboard.

image.png

Wayne Leake
 

Just thought, I should have added this picture of a finished board, showing the parts nicely.


Dang big picture.




--
k

Dan Schaefer
 

Thank you.  The picture helps confirm I put the parts in the right places.  Appreciate the clear picture. Harder to see on the manual  copies. 

Dan.  W3BU




On Feb 23, 2019, at 2:25 AM, Wayne Leake <wayneleake@...> wrote:

Just thought, I should have added this picture of a finished board, showing the parts nicely.

<dummyfile.0.part>

Dang big picture.




--
k

Dennis Yancey
 

I have one of those kits that I decided not to use. It is just as received from Sunil, if interested, let me know.
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72 and God bless
KD4EPG