Bitx40 circuit diagrams? #bitx40

Allen Woolfrey

The bitx40 circuit diagrams at

are not found.  Do they have detail or better resolution than the images on the bitx40 circuit description web page?

72/3, Al - va3iaw

Re: Source for female connectors/pins/manual crimp tool?

Doug W

On Fri, Jul 20, 2018 at 03:45 PM, Vince Vielhaber wrote:
The reel pins you get from Tayda are attached at the end where the wire goes in, not off of the ears. I've purchased hundreds from them and all were the same.
Good to know.  I have heard from others that they needed to be trimmed and that is how they look to me in the picture on their site so I have avoided them.  I like to be wrong when the right answer is better for me.


Re: KD6CEC code and Nextion displays, tuning skips steps #radiuno #ubitx


I am using normal tuning speed. Not fast tune.

I am quite aware of contact bounce and fitting capacitors etc.

The reason I ask, is to see if others using the CEC software with Nextion, are seeing a similar thing without having to fit any extra parts..  Ian's web pages don't mention any mods required that I can find.

glenn vk3pe

On Fri, Jul 20, 2018 at 11:25 PM, Michael Babineau wrote:
I have noticed this as well. For example when you set the step size to 50 Hz if you tune quite quickly it seems that the step-size

Are you sure that this isn't intentional ?  I see to recall Ian making a passing comment about variable rate tuning at some point.

Michael VE3WMB

P.S. I am really enjoying the ability to select the step size via touch screen in V2 of Ian's "Nextion" display code. This was a great addition.

I may have found another bug though. More on this later when I have had more of a chance to test it out. 

Re: uBITX No Power Output all of a sudden #ubitx


Nice fix Jim! Thanks for the write up.

all my best,

Mike N4EEV

Re: uBiTX Nextion issues

Björn Pasteuning

Checkout this link:
73' Björn de PD5DJ

Re: uBitX CAT problem on 40m #ubitx #ubitx-help #ft8

Tom, wb6b

Eventually I'll set up a proper ground island and shielding (like put my uBITX in a case), but in the meantime I'm having success with these toroids on the USB Cat cable. The black cable, with one at the radio and one at the raspberry Pi. This also helps reduce the RF noise from the Pi while receiving.

The clamp-on filter, on the white cable, is for the connection to a USB audio adaptor. I used a 2-3/8 toroid on the HDMI cable.

Transmitting on 80 meters was causing my internet to quit. I wound the power and ethernet cable to my router through a 2-3/8" toroid and that fixed that. I placed a grounded shield (aluminum "mini loaf" pan) around the power supply for the internet modem to get rid of the noise it was causing in the receiver. Eventually, I'll move all the wiring for the internet elsewhere, as far as possible from my ham station. 

On a side note, I used one of the 2-3/8 toroids to make a 1 to 9 impedance matching transformer for my 55 foot long (stealth) 80 through 10 meter non-resonate antenna. I placed another 2-3/8 toroid (with 10 turns of coax) 25 foot down the coax of the antenna cable to block the common mode RF. (The shield is the main counterpoise) Amazingly, it is a fairly good match for those bands, but I normally use it with an auto tuner.

I purchased these toroids from Palomar Engineering. The small ones on the black USB cable, were rated for 1 to 10 MHZ. The large ones, if I recall, were 1 to 30 MHZ.

Tom, wb6b

Re: uBITX No Power Output all of a sudden #ubitx


Thanks for the tip Jim.


Re: uBiTX Nextion issues



You have to use the .tft file for the 3.2 inch display, it sounds like you used the 2.4 inch file.


Re: uBiTX Nextion issues


So pleading ignorance, why do I have this large 1/2" band of black on the right side?  Is there something wrong? Everything else seems OK.

Re: uBiTX Nextion issues


DUH moment... I used the WRONG file for the Nextion!  I finally noticed the other files below!
Problem solved...

uBiTX Nextion issues


I purchased this Nextion 3.2" display:

So I've updated the uBITX software.  Then I've taken a 8Gbit (Sandisk, formated FAT32) and copied ubitx_32.tft onto it.  Hooked up properly to where the LCD used to reside.  When I power up the system, the display (reads at 90 degrees) Starts with "SD card update", but then quickly says "Model does not match" and " Device model NX4024K032_011R"  What am I doing wrong?  The version I bought said "enhanced".  Does that mean trouble?
Thanks, Jim W0CHL

Re: Source for female connectors/pins/manual crimp tool?

Vince Vielhaber

On 07/20/2018 01:26 PM, Doug W wrote:

Tayda while lower cost only has the connectors with the "ears" on them
from a reel that you have to trim off making them less than ideal.
You must have gotten a bad batch or listened to someone who had. The reel pins you get from Tayda are attached at the end where the wire goes in, not off of the ears. I've purchased hundreds from them and all were the same.

Now if someone has a source for pre-crimped wires like what comes with the bitx, I'd sure appreciate a link or at least a name of what they're called.

Michigan VHF Corp.

uBITX No Power Output all of a sudden #ubitx

Jim Sheldon

While prepping a V3 uBITX I had already built up to give to a friend of mine, all of a sudden the RF Power output went to ZERO.  Thought for sure I'd somehow blown 1 or both of the IRF510's, but I learned (and taught) electronic equipment troubleshooting during the later years of my 20 year US Army career and one point I learned was that nothing is always as it seems.

First thing I checked was voltage to the drains of the IRF510's -- ZERO (yes it was hooked up and turned on).  Tracing the voltage back, I had nothing on the supply ends of L8 OR L9.  I checked continuity between those same points of L8 and L9 and had good connections there. 

I found that I had +12V on the PA Power pin of P1 but nothing on the supply end of L8 which gets connected by a short trace to a very small VIA through the board and a short trace to L8 on the underside.  Looking at the underside, the trace was not burned but it turns out that tiny little VIA was open -- poor plating through the hole.  I put a piece of 30 gauge wire wrap wire through the via and soldered it on both sides.  This brought the +12 back to the supply side of L8, L9 and subsequently the drains of the IRF-510's .  Put it all back together and I now had full power again.

I've noticed in the past a few people having similar problems and not sure if they ever did find them.  This might be the cause and is definitely worth checking as there will be no visible indication of anything bad between the PA Power pin on P1 and the rest of the PA circuit.

Hope this is helpful to some of you.

Jim Sheldon, W0EB

Re: surprising CW sidetone value in uBITX Manager 0.11 #ubitx

Mike KK7ER

I think I see what is going on.  For example, in initSettings(), the sidetone value is getting read from the EEPROM:

EEPROM.get(CW_SIDETONE, sideTone);
But later on, it is getting overwritten if the value is not "sane":

if (sideTone < 100 || 2000 < sideTone)
  sideTone = 800;
So that explains why uBITX Manager is showing bogus values and yet normal values show up on the LCD.

73 Mike KK7ER

Re: K5BCQ click fix 2nd generation installed #ubitx

raymond bisseker <g3srq@...>

Still awaiting delivery of my uBITX....Hopefully next week?...Brilliant posts on this site...Helpful...Thanks guys.


Re: #ubitx-help Strong Audio Tones in and outside audio receive passband #ubitx-help

Jerry Gaffke

If you have a v4 with the socketed Nano, probably easiest to just buy a bunch of Nano's.
Find one that does not have the processor clock at the wrong frequency.

Be sure to buy Nano's that don't already have the pins soldered to the Nano,
since the pins must be added to the back side of the Nano.

The Nano's use a 16mhz ceramic resonator to determine the CPU clock frequency,
and that can vary by 50khz or more between units.
Apparently, harmonics of the 16mhz oscillator beat with harmonics of the 12mhz BFO, creating the tones.

If you hear the tones while using a v3 uBitx, try putting a finger on the (very dinky, about 2x3 mm)
ceramic resonator near the ATMega328P processor, on processor pins 7 and 8.
You will have to remove the LCD first to get your finger in there, but the radio will still work.
Since on the v3 uBitx the Nano is soldered down to the Raduino, it will be much tougher to
swap the Nano out.  Might be easier to add small capacitors (10pf) to ground from one or
both ends of the resonator.  But that resonator and ATMega328P are quite small, will be
a difficult solder job.  Might work to put insulating tape over the resonator, then grounded copper
foil over the top of that, effectively duplicating what happens when you put a finger on it.

There is also a 12mhz resonator associated with the Nano clone's ch340 USB chip.
This resonator is not active unless there is a USB connection to a host computer for a firmware download,
so interference from the 12mhz oscillator should not normally be an issue.


On Wed, Jul 4, 2018 at 06:19 PM, <groupsio@...> wrote:
Is replacing the Arduino still the easiest way to fix the 13kHz tone in the headphones?

Re: Another satisfied uBITX owner.


Used the stock mic element. Added the wind screen. I think 10 for 5 bucks from Amazon or ebay. 

Re: Another satisfied uBITX owner.

Kevin Rea

What did you use for the microphone element?

Re: logic mod for filter selection #arduino #ubitx

ajparent1/KB1GMX <kb1gmx@...>

FYI the diodes used were 1n4148/914.

Ruse the data bus for the display, you can do that.  Its better to keep them as
digital outputs but I've done that to get three outputs so that I can scan
multiple encoders with buttons and one input per encoder/button. 

The code for that is common-bus-encoders-master.  It works very well.
Not using it for bitx but handy for another project.

Created by : Jacques Bellavance, March 26, 2017
Released into the public domain.
This library is designed to use multiple encoders with the least amount of digital pins.
The first encoder requires 4 pins. the remaining ones require only one extra pin per encoder.
For use with quadratic encoders with 2 or 4 steps per detent,
and need to be actuated by hand. This Library does not use interrupts.
See the Tutorial for more information

Re: Source for female connectors/pins/manual crimp tool?

Dave New, N8SBE


I ordered:

100% Brand new high quality connector, pin headers and IDC cable kit
Package quantity: 635-Piece and 5-Feet 10-Wire IDC Cable

Package Includes: 
Dupont Connector Female / Male Housing Connector. 
1x2P Dupont Connector Housing Female-----------20-Piece
1x3P Dupont Connector Housing Female-----------20-Piece
1x4P Dupont Connector Housing Female-----------20-Piece
1x5P Dupont Connector Housing Female-----------20-Piece
1x6P Dupont Connector Housing Female-----------20-Piece
1x7P Dupont Connector Housing Female-----------20-Piece
1x8P Dupont Connector Housing Female-----------20-Piece
1x9P Dupont Connector Housing Female-----------20-Piece

210-Piece Dupont Jumper Wire Cable Female Pin Connector. 
210-Piece Dupont Jumper Wire Cable MalePin Connector. 

10-Piece 40 Pin 2.54mm Pitch Single Row PCB Pin Header 
10-Piece 40 Pin 2.54mm Pitch Single Row Right Angle PCB Pin Headers

5-Feet 10-Wire Rainbow Color Flat Ribbon IDC Cable

for $13.87 USD, and:

IWISS Crimping Tools for Dupont Professional Pin Compression Ratcheting Modular Insulated Terminal Crimper Pin 2.54mm 3.96mm 28-18AWG 0.5-1.0mm2 with Wire-electrode Cutting Die

for $22.99 USD

I'd say the tool dies look a LOT like the one I have for Anderson Powerpoles, but I'd rather have one that is specifically designed for the Dupont stuff than to take a chance that it doesn't fit quite right. I'm a great believer in proper crimping.

In any event, since I'm a Prime member, I will get both of those with free shipping in two days.

I figured that if I got a decent quantity of the housings/pins, I could share with my club mates, since we did a quantity buy of the uBITX, and a number of them are also ordering the case I got.  No sense everyone having to scour the Internet for missing connectors.


-- Dave, N8SBE

-------- Original Message --------
Subject: [BITX20] Source for female connectors/pins/manual crimp tool?
From: "Dave New" <n8sbe@...>
Date: Fri, July 20, 2018 12:57 pm


Sorry if this has been hashed over before on the list, but I couldn't find any reference to this, either here or on the various wiki/facebook, etc. sites I found.

I have a uBITX and one of the cases.  Between the two, there are a number of interesting PCBs, cables, etc.  There are two cables provided with the uBITX that are 8-way with female housings on one end of each cable (the other end is just loose wires).

The case comes with a front panel PCB, which has lands for 8-way BergStik-type male pins (which I was able to provide from my junque box).  Now I realize that I could've just soldered the loose wires from the cables provided with the uBITX into the front panel PCB, but now that I've gone and soldered all the male pins on the front panel PCB, I now need to find the appropriate female housings/pins and a manual crimp tool, to make it all look (and work) good/well.

I think I've found the appropriate stuff on Mouser, in their Amphenol/FCI brand, but I thought it might be helpful to find out what others on the list have used (or did they just solder the loose wires to the front panel PCB?).  A number of pictures I've seen of a uBITX installed in a case shows connectors on both ends of the digital and analog cables,  but no hint where to find such animals.

I did find a pre-made cable on Amazon (by searching on Relimate), but they wanted $90 USD for one cable, meaning that I would have to plunk down $180 USD for two!  That methinks goes against the spirit of the whole BITX thing, where the point is to come up with a reproducible inexpensive design.

So, links to messages, etc. would be greatly appreciated.

Thanks, and 73,

-- Dave, N8SBE