Re: uBITX full design

Scott McDonald

FWIW, if you haven’t already seen them, the IF amp boards - SMT type- are available on OSH Park very reasonably and are a great start for a stage by stage build.  They don’t have holes for mounting posts so a bit of ingenuity is required but they work well otherwise.

Good luck.  Scott Ka9p

On Sep 23, 2019, at 1:40 PM, MadRadioModder <madradiomodder@...> wrote:

In my mind… this is the obvious next step for the uBITx.  There is a good following of people here that wouldn’t mind building the radio from scratch… and it also allows for experimentation in each of the stages as one builds and tests.  If I ever get time, my goal is to make a set of boards stage by stage that can be fit together on a motherboard.  What better teaching tool?


For the rest, there is the completed (prebuilt board) uBITx that has become so successful.



From: [] On Behalf Of Ashhar Farhan
Sent: Monday, September 23, 2019 1:13 AM
Subject: Re: [BITX20] uBITX full design




I can arrange for a blank PCB if you want to solder it all up. it  hurts my wrist to do it all over again. i have done it several times to test the new boards. there is very little education in it. 

on the other hand, you might want to build a ubitx all by yourself. although it is a double conversion design, it is actually quite easy to build, stage-wise. beign by building the IF amplifiers. you will have to build six of those. get one going and duplicat the rest. each on a separate 2"x2" copper board.  you can hook up a raduino from the Si5351 board from qrp-labs and an antuino. using that as a signal generator, you can test/align the 45 Mhz filter and the LPF. At that point, you are done with the RF parts and you can choose to go with any audio amplification system.

i would encourage you to build it one stage at a time, test, measure and move on. great education!!


73, f


On Mon, Sep 23, 2019 at 4:06 AM Jerry Gaffke via Groups.Io <> wrote:

I agree with Curt.
A good student project would be to get the uBitx, and then try to improve it somehow.
Lots of fodder in this forum if looking for ideas of what to do.


On Sun, Sep 22, 2019 at 03:27 PM, Curt wrote:

Jerry gave a nice description of the board.  An EE named Allison has separately commented on optimizing the PA portion - and she went out and designed a better PA layout assisting Hans Summers at QRP-Labs (they currently offer this PA kit over there).  Years ago a prof somewhere got his students to build a QRP rig, Norcal 40A maybe.  I see you already built a McHF so I don't see a lot of upside to you building your own ubitx from scratch.  likely you have already dug into the nifty synthesizer components that are a key piece of modern QRP likes ubitx and QCX. 



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