Date   
Re: First Mod to µBitx = first screw up--Oh my #ubitx-help

Jerry Gaffke
 

Here's that excellent post  from AA9GG with the pin numbers for the uBitx and Bitx40 relays:
    https://groups.io/g/BITX20/message/47000

The relay datasheets number the pins as if the device was a 16 pin 300 mil wide DIP.
(The TDA2822 is an 8 pin 300 mil wide DIP, where DIP means "dual inline package")
But skips over some of the pin numbers because relay pin spacing is 200 or 300 mils instead
of the standard 100 mils.

Also, the uBitx schematic has pin numbering a bit different than the relay datasheet, 
has the relay rotated 180 degrees.

Jerry, KE7ER



On Thu, Jun 14, 2018 at 09:07 am, Don, ND6T wrote:
I believe that there was an excellent post a few months ago that showed the pin numbers. Perhaps someone can help before I can locate it?

Re: First Mod to µBitx = first screw up--Oh my #ubitx-help

Clark Martin
 

I believe that is due to some datasheets having the pin numbering rotated 180 degrees as compared to other datasheets.


Clark Martin
KK6ISP

On Jun 14, 2018, at 9:15 AM, Jerry Gaffke via Groups.Io <jgaffke@...> wrote:

Also, the uBitx schematic has pin numbering a bit different than the relay datasheet, 
has the relay rotated 180 degrees.

Re: Ubix & case for sale

Dave Dixon
 

HEY UP CHRIS,
                          ITS DAVE G0AYD,lost your phone number when my phone shit i8tself and deleted all my contactstrust tour well..tried to ring you but no responce.heres my my mobile 07735944744.wonder what version the mbitx is and can you send me pics plrase,im interested,regards dave


On 14 June 2018 at 01:50, chris gress <Chrisg0wfh@...> wrote:
I am selling my Unix untouched kit and untouched case both boxed case came from sunil lakhani is red UK will ship to euro land if postage covered selling for what they cost me £123.27 post free in the UK contact chris g0wfh tel 07482429329
Email chrisg0wfh at gmail . com to much work and no time for the kit thanks chris


Re: How hot is too hot? #ubitx

Allen Merrell
 

Mine in the oem state with 16x2 display never got too hot to hold. went to 20x4 display and it got HOT too hot to hold added a Nextion 3.2 enhanced and it got even hotter so I am considering building an auxiliary 5v supply off the 13.8v input line to run what addon's I add to it to get this load completely away from the raduino board.
73's  kn4ud
--
Allen  Merrell

uBitx has a bit too crispy / semi-distorted audio even on low signal levels #ubitx #ubitx-help

Mike
 

I have completed the uBitx and calibrated both frequency and BFO. The sensitivity appears OK. However audio has a strange crispy / semi-distorted sound to it.

I read the post from W3JDR https://w3jdr.wordpress.com/2018/04/11/ubitx-dynamic-range-improvement/#comment-1507  about biasing Q70 more strongly, however that only reduced the gain somewhat but didnt seem to help the crispy / semi distorted sound.

I have tried several headsets and a speaker. Same issue.

Anyone have any hints to what may be done to achieve better audio and get rid of that distortion effect?

Re: How hot is too hot? #ubitx

Bo Barry <wn4ghv@...>
 

I put a handy buck converter that has a voltage display on it and dropped the voltage to 8 volts with it, AND LABELLED THE PLUG.  
Currently using it with the addon arduino/display, but might incorporate it to the ubitx built in display.

Re: uBitx has a bit too crispy / semi-distorted audio even on low signal levels #ubitx #ubitx-help

KE6BB
 

Are you sure you have the BFO set and fine tuned?   Check out VK3YE's YouTube video to see how he fine tuned his BFO setting:

https://youtu.be/sXJmAhpAjeI

He is listening to his transmissions, but if my memory hasn't failed me, the setting affects both TX and RX.

Hope that helps.
--
Mark,
KE6BB

Re: How hot is too hot? #ubitx

Jack, W8TEE
 

Our 5" TFT color display can draw as much as 0.7A @3.3V, so we're working with a pretty hefty buck converter.

Jack, W8TEE

On Thursday, June 14, 2018, 1:18:25 PM EDT, Allen Merrell via Groups.Io <kn4ud@...> wrote:


Mine in the oem state with 16x2 display never got too hot to hold. went to 20x4 display and it got HOT too hot to hold added a Nextion 3.2 enhanced and it got even hotter so I am considering building an auxiliary 5v supply off the 13.8v input line to run what addon's I add to it to get this load completely away from the raduino board.
73's  kn4ud
--
Allen  Merrell

Re: How hot is too hot? #ubitx

ajparent1/KB1GMX <kb1gmx@...>
 

One of the big power consumers in the Raduino is the backlight for the display.
Before I tamed mine it was over 80ma!  At 20ma it was easier on the eyes.


Allison

Voice keyer - parrot - ISD1820

iz oos
 

Hi, what about using cheap ISD1820 voice recorders kits as voice keyers? They seem to me they have a really high output, something like half a watt on a 8ohm load. If they can be used would a audio transformer 8-1000ohm really needed or would just unnecessarily elevate the voltage without any benefit? Would a 1:1 audio isolation transformer a better choice. How much attenuation would be necessary to prevent any damage of the mic input of the ubitx?

Re: uBitx has a bit too crispy / semi-distorted audio even on low signal levels #ubitx #ubitx-help

Ralph Mowery
 


My receive and transmitted audio did not have much highs or lows in it.  The filter was only about 1700 Hz wide.  I changed the 5 capacitors from the crystals that are used for the filter from 100 pf to 82 pf ( think that is the standard value) and it widened out the audio range .  Probably should parallel some 5 or 6 pf capacitors across them to get about 85 to 88 pf as I did not have anything between a low 80 and the 100 pf.

That effects both the transmit and receive response, so you may want to make sure the transmit audio sounds about the same.

de ku4pt


On Thu, Jun 14, 2018 at 1:18 PM, Mike <rezycle.bin@...> wrote:

I have completed the uBitx and calibrated both frequency and BFO. The sensitivity appears OK. However audio has a strange crispy / semi-distorted sound to it.

I read the post from W3JDR https://w3jdr.wordpress.com/2018/04/11/ubitx-dynamic-range-improvement/#comment-1507  about biasing Q70 more strongly, however that only reduced the gain somewhat but didnt seem to help the crispy / semi distorted sound.

I have tried several headsets and a speaker. Same issue.

Anyone have any hints to what may be done to achieve better audio and get rid of that distortion effect?

_

Re: uBitx has a bit too crispy / semi-distorted audio even on low signal levels #ubitx #ubitx-help

Jerry Gaffke
 

If the audio is loud enough and has sufficient bass and treble and an SSB transmission is intelligble,
then this is not likely a BFO issue.  Could be a fault most anywhere between the antenna port
and headphone jack.   Though I would expect this problem to be somewhere from the demodulator
on through the audio amps.  

I would probably first try injecting a low level audio signal into the bottom of C50.
Could use audio from an mp3 player or broadcast radio headphone jack, but reduce the 
power level by a factor of a million or so (60 dB) first to avoid over driving Q70.
That means a voltage ratio of sqrt(1000000) = 1000  so from headphone jack to a 1 meg resistor
to a 1k resistor to ground, add a wire from the top of the 1k resistor to the bottom
of C50.  You also need a ground connection.  If that sounds good, then trouble is further back in the radio.
I'd look very hard at the demodulator if it isn't in the audio stages.
Trouble in the RF sections of the radio might mean birdies or weak signals, not so likely to 
create distorted audio.

Not sure anybody here knows what objectionably "crispy" audio sounds like,
you might give a link to an audio recording.

If there's another uBitx or Bitx40 in the neighborhood, you could patch in a signal from that other
radio into the your rig.  For example, inject a signal into c30 on your failing radio from the corresponding
point of that other radio, if the receiver now works well that means the fault is closer to your antenna jack.
Ideally remove c30 from both rigs, then have a 0.1uF cap in series with the
signal wire from one rig to the other to keep impedances about where they should be.  That wire is 
ideally a piece of 50 ohm coax, ground both ends of the coax braid. 

Good luck!

Jerry


On Thu, Jun 14, 2018 at 10:18 am, Mike wrote:
I have completed the uBitx and calibrated both frequency and BFO. The sensitivity appears OK. However audio has a strange crispy / semi-distorted sound to it.

I read the post from W3JDR https://w3jdr.wordpress.com/2018/04/11/ubitx-dynamic-range-improvement/#comment-1507  about biasing Q70 more strongly, however that only reduced the gain somewhat but didnt seem to help the crispy / semi distorted sound.

I have tried several headsets and a speaker. Same issue.

Anyone have any hints to what may be done to achieve better audio and get rid of that distortion effect?

Re: #ubitx-help #ubitx-help

hakan.sjostrom@...
 

I have got help for my RX problems. But nothing of what I could though about. In my home I hear a lot of signals with my little transistor radio but nearly nothing with the ubitx. At my friends house suddenly there was a lot of signals with the rig (and a dipole antenna). I also tested the LW at another place outdoors - no problems. So it seems the problem is in the enviroment of my apartment (combination with the indoor antenna?)
Anyway it looks a lot better now. And many thanks to you who tried to help me with my problem!
Håkan

Re: Latest Build, Mods and results.

Mike
 

Hi @Mharpen do you have a shematic of the audio amp circuit you used to compensate for the gain loss of the AGC circuit?

Swapping First and Second Line on uBITX Display with KD8CEC v1.08 firmware #ubitx

 

I just got my uBITX V3 wired up yesterday and decided to go ahead and load the latest available KD8CEC firmware this morning.

After playing around with it for a while I decided that I would prefer to have the Main VFO frequency and Mode displayed in the top
line of the display and the secondary info (VFO B etc) on the bottom line so I looked at the code and realized that there seemed to be a swap
happening between lines one and two under some circumstances. This quest ultimately lead me to the uBITX Memory Manager. 

Under 'User Interface' of the uBitx Memory Manager application (scroll way down), checking  the '1/2 Line Toggle' works to swap the first and 2nd lines
on the display, so I didn't have to change any code to achieve this. 

I did a search within this group and found reference to this feature in message #46400 but it was pretty low key so I thought that I would
reiterate this in case anyone was else has a preference for putting the more important info on the top line of the display.

Cheers

Michael VE3WMB 

Re: New RF AGC modification #ubitx

Mike
 

Hi. Is there an error in the wiring instructions of the coaxes here? -> http://www.nd6t.com/uBITX/Graphics/potmnt2.jpg

Shouldn't it be to K3 pin 3 and not pin 14?

(In the schematic on hfsignals.com pin 14 look like is ground?) http://www.hfsignals.com/wp-content/uploads/2017/12/ubitxr4.pdf

73

Re: How hot is too hot? #ubitx

Bo Barry <wn4ghv@...>
 

Yep, i got the 5A LM2596 version on eBay $8.00

Re: uBitx has a bit too crispy / semi-distorted audio even on low signal levels #ubitx #ubitx-help

Mike
 

Hi I actually have two uBITx radios. One that I have tuned the BFO on and another factory stock. I did swap in the other uBITx into the same cable harness: the "crispy / semidistorted" audio is exactly the same on both of them. Its kind of "cracking up" on the peaks. If i listen to a carrier, I hear the same effect. The tone is not clean.

Re: New RF AGC modification #ubitx

Don, ND6T
 

Well, looky there! Mike, I hadn't noticed  but it looks like Farhan moved the wiring from version 3 (the one that I have) to the other set of relay contacts on version 4 (the one that I am waiting for)! Good catch! As soon as I get my new boards I'll check that out and update the web site. I can hardly wait to see what else has changed. Just might have some more work to do. Hold off a bit, if you could. As soon as I get my new  board I will get right to it. Thank you.

Re: uBitx has a bit too crispy / semi-distorted audio even on low signal levels #ubitx #ubitx-help

Mike
 

Here is an example of how it sounds like. SSB signals kind of sounds like someone runs a strong RF clipper on them. If you wait until the last part of the clip you can also hear CW signals. Those signals are not too strong and should not distort.

https://groups.io/g/BITX20/files/180615_1218.MP3