Topics

ND6T AGC and Click kit wiring notes

Kees T
 

Decided to expand the title a little since I'm sure there will be more questions for Don, ND6T, on his designs.

Uploaded some pictures to the "Photos" section showing one alternative for AGC board mounting. It's under my call   K5BCQ  in the 5th group of photos.

We're up to 598 of the AGC and/or Click mini-kits shipped (a little more than I had anticipated ;o) and I'm about out of AGC boards (15 left) .......but orders have dropped off. I will order more if there is adequate demand. Also I understand the new Ver 4 uBITX boards have a "Click Fix" incorporated but apparently still no AGC circuitry ?

 
73 Kees K5BCQ

Bill Carpenter <nz0tham@...>
 

Thank you Kees!

73,Bill NZ0T

Nick VK4PP
 

Hi Kees,
Just wondering if you can confirm my DX order for AGC 2 boards is ok?

73 NIck VK4PLN

Nick VK4PP
 

Nevermind, I found the spreadsheet..

THANKS!

F1BFU - Fr - 79
 

Hello Kees

Kits AGC and Click fix arrived here in France.
State super FB.

Many thanks Kees for your job

73 QRO
F1BFI Gilles / FR

2018-06-19 20:06 GMT+02:00 Kees T <windy10605@...>:

Decided to expand the title a little since I'm sure there will be more questions for Don, ND6T, on his designs.

Uploaded some pictures to the "Photos" section showing one alternative for AGC board mounting. It's under my call   K5BCQ  in the 5th group of photos.

We're up to 598 of the AGC and/or Click mini-kits shipped (a little more than I had anticipated ;o) and I'm about out of AGC boards (15 left) .......but orders have dropped off. I will order more if there is adequate demand. Also I understand the new Ver 4 uBITX boards have a "Click Fix" incorporated but apparently still no AGC circuitry ?

 
73 Kees K5BCQ


Vince Loschiavo
 

I'm liking the board mount with the 3 pins...
Thanks
de
n2aie

alans77@...
 

Hi Kees: Thanks for doing a great job on the pop fix and AGC. Please send the link to the photos.

73,
Alan N4AYE

Kees T
 

Link to the Photos  https://groups.io/g/BITX20/album?id=42154
Link to the Files   https://groups.io/g/BITX20/files/K5BCQ

73 Kees K5BCQ

chris gress <Chrisg0wfh@...>
 

How do you order these boards is there a web page chris in the uk


On Wed, 20 Jun 2018, 21:06 Kees T, <windy10605@...> wrote:
Link to the Photos  https://groups.io/g/BITX20/album?id=42154
Link to the Files   https://groups.io/g/BITX20/files/K5BCQ

73 Kees K5BCQ

Kees T
 

Please see the "Files" section listed in the next note, below. All info is there.

73 Kees K5BCQ

Kees T
 

I have updated the AGC/Click mini-kit "ordered/shipped" list in the "Files" section per today's information. There will be some delay before more kits can be shipped because I'm out of AGC boards and have just ordered another 160. I have plenty of parts.

73 Kees K5BCQ

Glenn
 

Kees,
I think there is an error on the AGC pcb overlay. The hole marked as "5v" is actually ground. The hole adjacent is 5v.

glenn vk3pe


On Thu, Jun 21, 2018 at 05:14 pm, Kees T wrote:
I have updated the AGC/Click mini-kit "ordered/shipped" list in the "Files" section per today's information. There will be some delay before more kits can be shipped because I'm out of AGC boards and have just ordered another 160. I have plenty of parts.

73 Kees K5BCQ

bands11
 

Hi folks … I noted the same issue on my AGC board … and then I looked at the pads on the bottom.  Of course the square pads (indicating the indexed pad ...   [ ]   0  ... ) were easily seen and when I took them to be the non-ground pad, everything fell into place.  I suspected that the “5v” legend was simply to identify the connection pair for power and ground … there was no room on the board to put it on the other end of the connection pair.

So ….. after discovering the index pin, everything got hooked up just fine.  :-)

Thanks again Kees!

Bob Harbrecht
KE7QEQ

On Jun 21, 2018, at 10:13 PM, Glenn <glennp@...> wrote:

Kees,
I think there is an error on the AGC pcb overlay. The hole marked as "5v" is actually ground. The hole adjacent is 5v.

glenn vk3pe

<KEE_S AGC PCB 5V _ GND REVERSED.JPG>
On Thu, Jun 21, 2018 at 05:14 pm, Kees T wrote:
I have updated the AGC/Click mini-kit "ordered/shipped" list in the "Files" section per today's information. There will be some delay before more kits can be shipped because I'm out of AGC boards and have just ordered another 160. I have plenty of parts.

73 Kees K5BCQ

ENGINEER … Solving problems you didn’t know you had in ways you can’t understand.   SigCat




Kees T
 

Yes, it indicates the header "pair" ....just like on the Audio header pair .....not enough room. Be sure to instal the jumper if you are not using the RF Gain potentiometer.

Nice job on the board assembly. I see you got the diodes soldered in place.

73 Kees K5BCQ

 

John KJ4IFO
 

I got the kits, now to learn how to do SMT soldering.

Anyway, I measured the actual resistance of my stock of potentiometers to use with the kit, and none of them go all the way to 0 ohms - the lowest is about two ohms.  Seems to me like putting an extra 2 ohms in the antenna input line is not a good idea - or am I missing something here?
Would a higher quality potentiometer be more likely to actually get to 0 ohms, in the event this actually is a problem?

Appreciate any words of wisdom anyone can offer!

Ralph Mowery
 

I would not fool with the pot.  That was something before the fine nd6t kit.  I just put in the AVC kit without the pot and if works fine fo rme.


On Fri, Jun 22, 2018 at 5:45 PM, John KJ4IFO via Groups.Io <svsunbow@...> wrote:
I got the kits, now to learn how to do SMT soldering.

Anyway, I measured the actual resistance of my stock of potentiometers to use with the kit, and none of them go all the way to 0 ohms - the lowest is about two ohms.  Seems to me like putting an extra 2 ohms in the antenna input line is not a good idea - or am I missing something here?
Would a higher quality potentiometer be more likely to actually get to 0 ohms, in the event this actually is a problem?

Appreciate any words of wisdom anyone can offer!


Don, ND6T
 

John,
Since I work CW primarily, the manual control is a must. It also helps with extremely strong voice signals, not to mention AM reception (since it does not use the carrier level). The control is used as a potentiometer (voltage divider) instead of a rheostat (variable resistor) so the minimum resistance is not that important. I have some cheap 500 ohm pots that work wonderfully. A 10K pot is just fine. Taper is more important. A logarithmic (audio) taper works best since a linear taper will put all the action at one end. Nothing is critical. Yes, a good pot with a one ohm resistance and a very good ground will give you a few more dB attenuation but that doesn't make that big of a difference in operation. Remember that the attenuation of the pot is additive to the AGC operation, a real plus. Oh, and a manual RF gain is also important if you have a lot of background noise! 73, Don

Tim Gorman
 

Hard to emphasize this enough. My problem is no space on the front
panel or I would have one added! I may just drill a hole in the back
panel!

Even on a rig like the FTDX-3000 it helps if you turn the RF gain down
in the presence of noise till the S-meter just flickers. The DSP even
does a better job quieting things down that way!

tim ab0wr

On Fri, 22 Jun 2018 16:12:11 -0700
"Don, ND6T via Groups.Io" <nd6t_6=yahoo.com@groups.io> wrote:


Oh, and a manual RF gain is also important if you have a lot of
background noise! 73, Don

Mark M
 

Hmmm...I've had some issues with mine. I wonder if I may have reverse powered it before I realized the pad by the 5V marking was ground. I don't imagine that would be good for it.

I guess I could build the second one I have & see if it makes any difference. Or maybe just replace the transistors.

Mark  AA7TA

Stephanus K6NG
 

Quick questions... to add rf gain I just wire the VR to the AGC board? And how do I wire an AGC fast and slow switch?
Thanks,
  Stephanus