D4D update


Adam Rong
 

Folks,

I promised to provide some update about D4D. And here it is. Modified the 20m version. Need PCB update.





Thanks,
Adam


tem494@...
 

Adam
Please let everyone know when you get the new board in production. Love the D4D it really started me in the FT8 world. Excited about more power from the 20 meter version

tom 
k0amd

On Mon, Aug 9, 2021 at 7:54 AM Adam Rong <rongxh@...> wrote:
Folks,

I promised to provide some update about D4D. And here it is. Modified the 20m version. Need PCB update.





Thanks,
Adam


Adam Rong
 

As the PCB design change takes a while, I am offering a modified 20m version D4D at this moment, see photo below. You can PayPal 43 USD to my PayPal rongxh@... and leave your ship to address. If you have questions, please contact me offline rongxh@...


Thanks,
Adam


Jim Pruitt
 

Hello Adam.

I am curious what the "modified" modification is to the D4D.

Thank you.

Jim Pruitt
WA7DUY


On 8/14/2021 10:20 PM, Adam Rong wrote:
As the PCB design change takes a while, I am offering a modified 20m version D4D at this moment, see photo below. You can PayPal 43 USD to my PayPal rongxh@... and leave your ship to address. If you have questions, please contact me offline rongxh@...


Thanks,
Adam


Adam Rong
 

Hi Jim,

Main modifications:
RX: Remove front end crystal to allow better sensitivity at the cost of the BCI. It makes sense for 20m.
TX: Change PA bias from class A to class C, change the final from C1162 to BD139, add a capacitor to LPF to make it higher efficiency and higher RF output.

No change to VOX yet to be able to use the original PCB. I will post a part list to reflect the changes. Others are very similar so you still can refer to the original kit assembly manual.

Thanks,
Adam

2021年8月15日 下午3:27,Jim Pruitt <jpruitt67@...> 写道:

Hello Adam.

I am curious what the "modified" modification is to the D4D.

Thank you.

Jim Pruitt
WA7DUY


On 8/14/2021 10:20 PM, Adam Rong wrote:
As the PCB design change takes a while, I am offering a modified 20m version D4D at this moment, see photo below. You can PayPal 43 USD to my PayPal rongxh@... and leave your ship to address. If you have questions, please contact me offline rongxh@...
<微信图片_20210815131937.jpg>

Thanks,
Adam