Just ordered  Microcontroller Projects for Amateur Radio; and received confirmation email from ARRL.  Somewhere in the process it said  "shipping mid sept". the confirmation email just has standard boilerplate - ships within 3 days; allow  1-7 days for delivery. it will be hard waiting

Owen,
Aaron had found the issue and is fixing the transmit problem.  It was a blown Q90.  He is now asking about the addition of back to back diodes to prevent that from happening again. 

Thanks for the suggestion.
73
Evan
AC9TU

Aaron,
I was going off of the numbers given on the HF Signals schematic (they are the same for all version since 4 that I know of):


You will need to trace out the wiring on the board to find the correct pins.  Note that the coil is listed on pins 8 and 9.  using your diagram it would be 1 is the upper right corner, and counting pins on twice the pitch as the actual pins, then going around in a counter-clockwise (TOP VIEW) direction you can make the assignments work. (strike through numbers are not used)

   8   7   6  5   4   3   2   1

   9 10 11 12 13 14 15 16

73
Evan
AC9TU

Mario,

Before working on the AGC wiring, I would make sure the audio amp and the rest of the rig is working.  

I assume that you will be using the Front Panel PCB supplied and that you have solder onto it all of the parts.  I will also assume that you have wired the tuning encoder and the optional 4 pin mic connector if you will be using it.

There are then 2 connectors left on the front PCB:
1 - A three-pin connector for the volume control
2 - A two-pin connector for the "speaker" if the audio amp is not used.

The speaker connector on the audio amp (2 pin polarized) is the same as the speaker connector on the front PCB.  This allows you to first make sure the mainboard and controls are working before you add the audio amp.  Just be sure to make the speaker wire and plug long enough to reach the audio amp speaker (LS) connection.  You still need to make a 3 wire plug to 3 wire plug jumper to connect the volume control that you mounted on the audio amp board.  I would also connect one of the 2 wire plugs to the inside and outside of the volume control line.  There are extra holes that allow you to solder in the red and black (black should be ground) to allow connection to the AGC after you have the audio amp working.  When you are ready to add the audio amp, you lift the speaker plug from the front PCB and move it to the speaker output of the audio amp and wire a 2 wire jumper from the front PCB speaker jack to the Audio In jack on the audio amp.  You will need to adjust the blue variable resistor to limit the maximum volume and prevent feedback.

Once you have everything working, including the audio amp, THEN start on the AGC.

I found getting the AGC to work the hardest part of the assembly.  The pictures of where to tie in the IF lines do not match the schematics given.  I followed the schematics and wired the IF to go across R10.  I was also confused by the AGC socket on the audio amp board.  That can be used, however, the S meter will fluctuate up and down, as well as the AGC limiting change with volume control setting.  The original design lists the connection of the AGC input to the High and Ground of the main volume control, and that is where I connected it (the 2 wire jumper you soldered into the extra holes on the audio amp that parallel the large volume control).  Seems to work properly after adjustment. 

One caution is to ensure that you soldered in the 2 and 3 pin connectors in the correct facing, otherwise, you can short out the signal as normally the black wire is ground and the red the signal or positive connection.  I got that wrong on the audio amp AGC out connector.  To compensate I changed the AGC In connector on the AGC board (it was easier to rework that board) to work with the AGC out from the audio amp until I found that that connection did not work as I wanted.  Now I have two 2 pin connectors that are in "backward." Only the one on the AGC board is in use.

I apologize if the above is not clear.  I do understand your confusion, and even with very good schematic skills I still had to rework most of the wiring in the kit because there is conflicting documentation provided for a number of areas, not just the Audio Amp and AGC.

As curt suggested in one of the earlier emails, for the uBITX it is always better to test the rig as close to stock as you can.  Usually, that means temporarily wiring up the rig outside of the case and verifying that all is working, including the stock display.  Then you know that the problem is not with the basic board and is aligned at least close to good.  There have been enough issues without adding more with kit wiring mistakes.

Above is my understanding of the rig at this point.  Others may have better information or different experiences.

Good Luck!
73
Evan
AC9TU

Evan, 
K1 does not have a Pin 12

--
'72

Hello,

Am 20.08.2020 05:40, schrieb vu3gwn:
[...]

So far, I have got the all peripheral boards soldered except audio
amp.

Do you have a AGC too?

[...]

73

Mario Koppensteiner
OE5MKE

Hello Evan,

Am 16.08.2020 12:59, schrieb Evan Hand:

Mario,
The Mini manual that Rick Price provided contains the following
information from HF Signals:
https://www.hfsignals.com/index.php/ubitx-wire-up/

I saw this page already. I does not explain how to connect the AGC and the AMP to the board.

Both can be used to wire-up the uBITX v3, v4, or v5 manual with the
stock configuration. I would highly recommend that you verify stock
operation before you add the Nextion display. You might want to do
that before you mount it in the case.

I'll have a try when I have connected all the wires.

[...]

73

Mario Koppensteiner
OE5MKE

Hello Mark,

Am 17.08.2020 14:43, schrieb Mark M.:

Hi Mario,
The diagram is actually good for three versions (v3, v4, v5). The ham
who posted the one you looked at just put a wrong title in (probably
because he had a v5). The original diagram was done by W4RJP and was
for the v3 (see link further down that section). The only difference
between the three versions are some mainboard changes, the connections
are still all the same.

thank you for your response.

I still need to know how to connect the AGC and the AMP to the ubitx board.

73

Mario Koppensteiner
OE5MKE

Hello Evan,


Am 17.08.2020 13:23, schrieb Evan Hand:

Mario,
From the links and your description, I assume that you have an
Amatuerradiokits case with the audio amplifier.

Yes I have.

If that is correct,
then the data that I have shows a TA4225 (not a TA4425) audio amp IC
as the audio amp. That is a 5 terminal device, not 3. That board is
very cramped, so it could be that the silk screening is really
pointing out the TA4225 5 pin socket and not the 3 holes that are
close by.

Sorry for the confusion. The part has 5 terminals. That's true.l

Attached are the 2 pdf files that I have for the audio amp.

I saw this already in the documentation. On the first pdf there are 3 terminals shown. The top one is for the power. the middle is labed "A/IN" and the bottom terminal is labled "AGC V". Both Terminals do have 2 pins each. Where should I connect this pins of the 2 terminals?

My guess is that the 3 hole location is for the onboard "volume"
control that is really a maximum volume control as the front panel
volume control is used to adjust the volume in operation. You should
have a blue 3 terminal variable resistor that goes into that location.

true

[...]

Please help me to get this AGC and the AMP connected.


73

Mario Koppensteiner
OE5MKE

Hello Bob,

Am 16.08.2020 03:22, schrieb Bob Lunsford via groups.io:

If I remember correctly on my V4 build, there are/were no specific
assembly instructions. I used the block diagram for the wiring which
made sure to connect everything where it needed to go.

Did you are the AGC and the AMP too?

[...]

73

Mario Koppensteiner
OE5MKE

Hello Rick,

Am 20.08.2020 00:40, schrieb Rick Price:

Hello Mario,
Yes, I saw in one of your messages after I sent the file that you had a
nextion case from amateurradio kits. If you still do not have the
instructions for assembly follow the link below and go to the bottom of the
page. There you will find a file with all of the instructions to download
for the ubitx nextion case.

https://amateurradiokits.in/downloads/


I did download this 7z archive already. There are lots of pictures included of an already assembled ubitx. most of the wires are brown and black on the pictures and you can't follow the single wires on the pictures. So I still do not have a plan how to wire the terminals of the AGC and the AMP.

Please help!

73

Mario Koppensteiner
OE5MKE

On Mon, Sep 14, 2020 at 11:49 AM, Gerard wrote:

try LTSpice 17, you can simulate electronic circuits.
See examples on the soft

Your message is a great reminder that I need to get back to learning better how to use these tools.

By the way, here is a direct link to the Analog Devices LTSpice download page:
https://www.analog.com/en/design-center/design-tools-and-calculators/ltspice-simulator.html

I've also played a little with ngspice:
http://ngspice.sourceforge.net

And there is another that I don't recall at the moment, that was an expensive paid product where the developer retired and now offers it as a free download. Anyone remember which this is?

One of the schematic capture cad packages I was using had Spice "integrated" into it, but setting up the signal generators and monitoring (test) points was still somewhat difficult. I'd like to improve my early beginner level of ability with Spice. It has been a while since I used these and have likely forgotten all of the little I knew already. 

For those that are more experienced with Spice, what is your favorite? Any practical hints? Anyone know of any good tutorials?

Tom, wb6b

Nigel,

Just checked sotabeams site again and this time it responded. That filter has a message stating that more stock is due in Autumn.

Reg                      G4NFR

hello,
i think you know some software helpfull like RFSim99, Dishal, Tore calculator.

try LTSpice 17, you can simulate electronic circuits.
See examples on the soft

cdt

Hi Nigel,

The two stage filter I used came from -

              https://www.sotabeams.co.uk/audio-filters-and-more/

I gather you have already looked at them ? They do a couple of cheaper dual bandwidth filters, one for SSB and CW and the other one specifically for CW. I don't intend using the uBitX for anything but CW so that was the filter I bought at aprox. £29.

The bad news... I have just looked at their site and that filter as well as other stuff is shown as out of stock. It won't let me click on it so there seems to be no further information at the moment. I know it has recently changed ownership so I don't know what is going on. Perhaps they are just out of stock - or - is the product line being streamlined ?
If you were interested in a filter you would have to contact them to find out what is happening.

It would be a pity if they dropped it as it is a very good filter and not a bad price.

Dual Bandwidth Filter Modules SSB/CW

Reg          G4NFR