Re: uBitx FT8 problem

John P

Do you have split mode enabled in WSJT and not in the radio? In split mode, WSJT plays with the transmitter frequency and the audio tone frequency to keep it in the middle of the bandpass. It sounds like the frequency is being changed but not getting changed back after transmitting
John - WA2FZW

Re: Low Pass filter inductor question. #filters


I've built the lpf for 40 and realize there is plenty of room for putting the 20 meter filter on the same board.  I thought I'd manually switch them.  So does this switching work?  What I mean is, should both legs be switched,  will I get any weirdness from the shared ground?   Sorry for the poor diagram.

Re: uBitx FT8 problem

Doug W

I am not using CAT control so I can only guess but if that is the only time you see this behavior I would start by looking at how well shielded your usb cable is (or is not).

Re: uBitx FT8 problem


Controlling with CAT cable. WSJT-X program controll automaticly,then you set 20m band program set frequency 14,074mhz on the radio...

Re: uBitx FT8 problem

Doug W

How are you controlling your frequency on the radio?

uBitx FT8 problem


Hello,one question about working on digimodes FT8 with uBitx... after transmiting , the frequency drops downthrough 1kH on uBitx display.for example: then frequencie is 14.074mhz after transmit drops down to 14.073mhz. After second transmit drops down to 14.072mhz and so on... Im working with WSJT-X. How to solve the problem? Thanks.

Re: Adding /modifying firmware. #firmware


Hi Mike, 
I looked up ver 1.1  memory manager and found the place to enter the call letters .  I noticed his new version does not have all the spaces on the left that the old one had.
I couldn't seem to find any instructions other than Dr. Lees on the old version (which I didnt understand)
A couple of questions
1) Baud rate?  What is it.  Then connect
2) Enter KM4TRT across from "my callsign" and chk the box  Do I have to enter anything in the text box above?
3) Then "write to bitx"  and done?

Andy  KM4TRT

Re: I find This Shorted Circuit on Raduino, here the pics..plz Help? #ubitx-help


AM is difficult due to carrier and bandwidth more than SSB filter.
It was never meant to be a AM receiver.  To do AM well the filters would
have to be 6Khz wide and that is far wide for SSB use.

SSB should be fine as that was the design. 


Re: I find This Shorted Circuit on Raduino, here the pics..plz Help? #ubitx-help

sdr freak

i have now tried almost everything that was within my reach.

now i had decided to give up on this fight. but on the other side i don't want to be a looser so i don't want give up because i felt only lucky when i have win this fight even its hard work but i have no other choice i have to must to work on and on till success comes 

NO i don't want give up, no no no i was not allowed to give up.

i'm back here again, to ask a bit better for the reception of a AM radio transmitter and like to know what you think it has to sound in yours to do with a damaged component or circuit, perhaps something like a bad (transistor,ic or maybe capacitor and induction or relay) on the circuit board, which breaks the modulation so much.

i don't think it works to receive from the AM transmitter or SSB language.

have you success when you want to receive an AM station on Ubitx(3) and can anybody please make a short video from his AM receive,and SSB receive how it should sounds, this would be very nice to see this for me.


Joe Puma


So I installed the ND6T and I think its working but the results are questionable. It seems to decimate my signal completely only allowing the littlest of signal in. I have to turn up the volume all the way to hear anything. With it inline it obviously ruins the experience of the IF out and waterfall as it reduces RF on the whole viewable band. My IF tap might need to be moved somewhere else, not sure if it can be put before the AGC as that’s a different stage before 45mhz crystal and mixing right? (shooting in the dark here).  We can address that later.


Another thing I noticed as the ND6T AGC introduced some spikes back into the signal path. I put the AGC after the BCI filter thinking it would be better to AGC a cleaner RF signal without all that AM IMD. I’ll post a pic of the bard layout so you can see my solder work and where I put the components.  I don’t think I messed up there but its odd that when the AGC is in place the overall signal drops at least 60-70%. Yes I can some signals but weaker signals just disappear. I figured that my signal wouldn’t be attenuated maybe even amplified if signal was lower then expected and then just attenuate the stronger signals.



This is with the AGC inline by disabled with the jumper across JP1. There are some noticeable spikes when inline compared to when its not. I don’t have a current comparison without it inline.




This is a shot with the AGC enabled. Jumper on JP2. The signal is mostly gone. I was playing with the volume control and where you do see signal further down the water fall is when I had the volume knob turned up. You can see the evenly spaced spikes too.









Sent from Mail for Windows 10


From: Joe Puma
Sent: Monday, September 24, 2018 7:00 PM
Subject: Re: [BITX20] ND6T AGC


Thanks everyone. I was able to secure a kit, thanks Mark!





Sent from Mail for Windows 10


From: Dennis Zabawa
Sent: Monday, September 24, 2018 1:46 PM
Subject: Re: [BITX20] ND6T AGC


You can get a board ONLY from:



Re: 10K Tuning Potentiometer has a very small range for BITX40

Allard PE1NWL

Hi Michael,
in a standard unmodified BitX40 the tuning range is only 50 kHz.
When you reach the end of the pot "fast step up/down" will occur so that you can still operate the entire band.

If you want to increase the tuning range so that it spans the entire 40m band, you could install a 10-turn pot and upgrade the firmware to v1.28.
Download it from (instructions included).

73 Allard PE1NWL


iz oos

That should be a very fine part provided the vendor is reliable.

Il 28/set/2018 04:02, "Joe Puma" <kd2nfc@...> ha scritto:

I found this on ebay, looks like its in spec?


Manufacturer: Coilcraft

Part Number: WB2010-1

  • Wideband RF Transformer
  • Imp. ratio pri:sec: 1:1
  • Frequency: 40KHz - 175MHz
  • Pri: L min 95uH, DCR max 0.200
  • Sec: L min 95uH, DCR max 0.200
  • Case DIP-5, through hole




Sent from Mail for Windows 10


From: Dexter N Muir
Sent: Thursday, September 27, 2018 6:33 PM
Subject: Re: [BITX20] IF OUT


AUDIO transformer! Anything over about 20kHz (maybe 50) severely attenuated.Useless at MHz of IF/RF. Very useful for isolation of sound card to avert ground-loop hum.


Re: uBIT and antenna connector and Nextion 7"

iz oos

As my local store offers good BNC at a reasonable price I opted to use BNC connectors for all RF homebrew stuff. They have the clear advantage of quick plugging in as opposed other connectors, SMA, N, PL. They are just more convenient. When I use a tuner I tune with an antenna analyzer and plugging-unplugging BNCs is fast.They are easier to assemble too and a good choice up to microwave.

Il 30/set/2018 21:05, "Rich" <admin@...> ha scritto:
This one is going to be base station at home and won't be moving.  I've already got plans for another one to go mobile :P

Re: Modified Baofeng Mic on BitX40 with case

Dexter N Muir

I'm suspecting the Baofeng mic relies somewhat on its housing and input circuitry for audio tailoring. BitXes don't - they're essentially hi-fi until the modulation and RF filtering, a possible reason the supplied element works best.

'noddling', ZL2DEX

Re: Modified Baofeng Mic on BitX40 with case



My findings exactly. This is why I used the ubitx supplied element instead of the Baofeng one, and the same with my current cb mic... 

Re: Grey case OUT OF STOCK

Praba Karan

At where?...Is this related to Sunil's case?

On Mon, Oct 1, 2018, 12:58 AM Tom <tomnagy@...> wrote:

Website shows grey case out of stock.

Can I expect this case to be back in stock with a few days??

 -Tom, W3TLN

Re: Adding /modifying firmware. #firmware

Mike Woods

That’s right!  

Your call sign is entered using  a third bit of software - uBITX Manager that runs on Windows and interfaces to the Raduino via USB.  You can set a whole range of parameters for the uBITx using KD8CEC’s uBITx Manager.


On Mon, 1 Oct 2018 at 4:44 AM, KM4TRT via Groups.Io <> wrote:
So if I buy say the Adifruit cable with the built in FTDI and download the driver, then I can download direct to the Nextion with the 4 pin connector instead of the sd card?

Re: BITX40 Potentiometers for volume and tuning

Dexter N Muir

The value of the pots is not critical. Log/Audio taper for Volume and Linear for tuning. As noted above, the middle tab of the tuning pot may not be the wiper - particularly if it's a 10-turn - and yes 10k works well there, but if watchagot is greater 10nF wiper to ground bypass..

Re: 10K Tuning Potentiometer has a very small range for BITX40

M Garza <mgarza896@...>

Is this a 10 turn pot or regular? 

My previous comment is for a 10 turn pot.

Marco - KG5PRT

On Sun, Sep 30, 2018, 10:02 PM M Garza <mgarza896@...> wrote:
Please verify that the potetionmeter is wired correctly.  The middle tab is usually not the connected to the wiper.


Marco - KG5PRT

On Sun, Sep 30, 2018, 9:49 PM Michael Trager <mtrager1@...> wrote:

Anyone know why the range is so small?


Do I need an update for the display/ VFO?



BITX40 Potentiometers for volume and tuning

Michael Trager <mtrager1@...>

What is the value of the volume pot that should be used?


Tuning Pot = 10K ???