Hi,
I recently built my ubitx, and after assembling
it received perfectly.  I just got my HAM license,
so I decided to see how the cw key function worked.
There seems to be a problem.

I am using the stock software which came with my
July 2018 delivered ubitx.

The PTT function works perfectly, just the slightest ground
puts the ubitx into Tx voice mode.

With CW, the story is different. 
First, the instructions are pretty shoddy, and only because
I could trace the wires from pictures in some setup instructions
was I able to figure out the wiring to the various 1/8'' female 
connector sockets.

I found there was no mention of the keyer socket PIN 3 connection
to the yellow ground wire of the Arduino, and it seems that
I needed to make a wire jumper to connect the keyer socket ground
to the Arduino yellow wire at PIN 4, the Arduino ground.
I guess they assumed a metal chassis would make the connection?
I have a plastic chassis.

So OK, got that glitched fixed and I fully expected it to work.
I had 5 volts connected to the 4.7k resistor, and the blue and green
wire connections were correct.

When I tried to key, nothing happened. I thought it might be a dirty
straight key, so I tried monmentarily jumpering the blue wire to
ground. It correctly went from 5v to 0v on each contact.

Now this is the weird part. If I repeatedly touched the blue wire
to Arduino ground ( yellow wire ), the cw tx mode would suddenly
start, with TX power and proper sidetone, then suddenly stop.

There is no pattern to trigger it. If I repeatedly touched and 
shorted the blue to yellow ground, I would randomly get
a burst of dits and dahs, then it would stop. I could repeat this
over and over, but without finding a definite pattern.

I thought maybe the Arduino board had a bad solder joint,
or some other intermittent problem, but I'm also wondering
if the stock software is flawed in the cw portion, and the Arduino
is having a hard time detecting the voltage drop of the key.

Before I go any further in ripping this thing apart, I would
hope one of the ubitx experts can provide an answer to this.

Thank You,
Joe Milosch, KN4OND, Mauk, GA, USA

?

Bo have you tried the 2N2222A or 2N2219’s yet? Although I haven’t added sockets I did replace all 2N3904s with 2N2222A starting with Q90. My output has increased on the upper bands.?

?I know this is an old topic, but I want to do some SIMPLE tinkering & learning.
I put 'socket pins' in for the 6 3904s thinking I could simply find some 'hotter' replacements. ?

Well I tried some 5109 and 2369s found on eBay. No noticeable improvements noted.

Then I tried my hand with LTSPICE, having used in since the 60's and taught it until '06. ?One of the transistors was in their library and I think I added the model for the 5109 correctly.
Not sure my setup is 100%, but I did get similar dismal results.
Anyone have some transistor types that may work.?
Not interested in other mods YET.?
I used to be addicted (and very skilled) in several versions if SPICE. Still have the MicroSim version somewhere.
Bo W4GHV?
??

?I know this is an old topic, but I want to do some SIMPLE tinkering & learning.
I put 'socket pins' in for the 6 3904s thinking I could simply find some 'hotter' replacements. ?

Well I tried some 5109 and 2369s found on eBay. No noticeable improvements noted.

Then I tried my hand with LTSPICE, having used in since the 60's and taught it until '06. ?One of the transistors was in their library and I think I added the model for the 5109 correctly.
Not sure my setup is 100%, but I did get similar dismal results.
Anyone have some transistor types that may work.?
Not interested in other mods YET.?
I used to be addicted (and very skilled) in several versions if SPICE. Still have the MicroSim version somewhere.
Bo W4GHV?
??

Hi Hiro, nice analysis, if I understand right if you add also any 30mhz (also like CB) lowpass filter you may transmit on 15m band. Isn't? Is the Trio tuner a simple pi-tuner? I have just done a variable low pass filter with a double 450pf air variable capacitor a six position switch and a 130-7 toroid and looking at PC the results from my antenna analyzer it seems better than expected.

Il 17/ago/2018 16:39, "JJ1FXF" <jj1fxf@...> ha scritto:

Hi, all.

Attached is a PDF file which shows the results of measuing spurious emission on my uBitX which I haven't modified its hardware/software at all.

Here, in Japan, the spurious emission should be less than -50dBc and so the list indicates I can use my uBitX with a Pi-C antenna tuner, but not on 15m unfortunately.

This time, I checked only the CW transmission beccause I had a problem to measure SSB case. It would be very much appreciated if someone could advise to me.

To measure the spurious emission on SSB, at first I need to saturate the PA output by the mic input of so called "pseudo voice" that is 1.5kHz sine wave, and when the output is saturated by increasing the input leve, then 80% of the input level will be used to measuer spurious emission, the Lab guy explained to me.

However, uBitX output won't be saturated which means I couldn't observe the flat level of PA output as increasing the input (pseudo voice) level, but suddenly the output level falls down to a few mW.

The Lab guy said it would be because uBitX didn't have an ALC - Auto Level Controller of the mic input.

So please advise to me how I can saturate the output (PA) level with such a "pseudo voice" input? Maybe bring an external mic compressor? However, how can I observe the flat level of PA output?

Thank you for reading my long email. Hope someone can help me. If you are interested in screen shots of the spurious analyzer, feel free to email me.

BR,

// hiro, JJ1FXF