Topics

homebrew ubitx PA #bitx20help #bitx40help #bitx40 #ubitx-help #bitx20

circular.simetry@...
 

Does anybody have the pcb layout for standalone PA and LPF of the ubitx ? Thanks în advance.

Curt
 

The PC board layout is a bit sensitive to HF signals. Why not purchase the similar PA from qrp-labs, certainly less expensive than doing your own board. Also Hans and Allison did lots of work to improve its performance.

Curt

ajparent1/kb1gmx
 

The general answer no one has.

The amp mentioned is a considerable improvement but it was designed
for a trx that provides the needed 25 milliwatts drive.   The predriver and
driver in the ubitx is still needed and they have issues as well.  That and
grafting it to the ubitx would be a challenge for the non RF experienced.

No one I know of has done a single board replacement amp that
can do 10W from the output of the low pass filter.   Its a difficult
design to get that much gain on one board without VHF layout
the level of ground plane needed for stability.

Allison

Curt
 

Thanks Allison for clariying. Based upon the message title, I am thinking the application here is a homebrew project. As for the exact number of watts, well enough is involved that I imagine merely a good irf510 amplifier is being sought. I think I recommended the best one around that uses a printed board.

73 curt

Dave Dixon
 

hi curt,
            G3PCJ Walford electronics here in the uk has  produced a linear,mine and a friends use a 5 watt qcx to drive it up to 45 watts on 40 using a pair of irf 510s.but can be made for any band..regards Dave.


On Sat, 2 Nov 2019 at 03:15, Curt via Groups.Io <wb8yyy=yahoo.com@groups.io> wrote:
Thanks Allison for clariying. Based upon the message title, I am thinking the application here is a homebrew project. As for the exact number of watts, well enough is involved that I imagine merely a good irf510 amplifier is being sought. I think I recommended the best one around that uses a printed board.

73 curt