Date   
Re: calibrate v4 ubitx

Jerry Gaffke
 

I zero-beat.
This beatnote thing wasn't well thought out, you want to move the BFO too,
far enough to avoid hearing the opposite sideband.
Left as an exercise for the reader.



On Thu, Jul 19, 2018 at 04:31 PM, Jerry Gaffke wrote:
This line of code:
    unsigned long clk1 = clk0 + 44995000;      //  clk0 + the center of the 45mhz crystal filter
could be changed to 
    unsigned long clk1 = clk0 + 44995000 + beatnote;  
where beatnote is an audio tone of perhaps 500  in Hz.
Then use a frequency counter on the speaker leads to measure the resultant audio tone,
twiddle the encoder till the frequency counter reads exactly that 500 hz.
With this change, you no longer need to find true zero beat, as zero Hz may be hard to find
given the capacitive coupling through the audio amp.

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

Jack Zielke
 

Version 4 has a socket for the Arduino so that was not going to be so bad.  I bought the RobotDyn Nano.  It turns out that the headers are on the opposite side as the one that comes with the radio.  I did not notice and plugged it in.  Nothing showed up on the display and the 5v regulator got very hot.  I turned it off and compared them a little closer and noticed the difference.  I put the old one back in and the radio appears undamaged.  I have not really tested it yet, just a power on, tuning (no antenna), and volume control appeared to work.  I plugged the new Nano into my computer and KD8CEC's Memory Manager was able to talk to it so this mistake might not have been a costly one.

Re: uBitx Prototype (PCB)

Robert Ogburn
 

Looks nice.  

Perhaps pin headers for audio derived AGC add on, pin headers for de click add on, pin headers for VOX add on.

Nice to have test points, I make them with a filled pad and silk circle+"TP1 (etc).  

Consider adding 2.54mm pin fields for power and ground and be certain that all power and ground islands are well stitched together.

As to the audio output stage.  Consider adding header pins for pwr, gnd, in and out.  

The builder could provide the choice of amplifier type or install the TDAxxxx part.

Several Chinese offerings 

here is one https://www.banggood.com/10Pcs-XPT8871-5V-5W-1A-Single-Channel-Mono-Digital-Audio-Amplifier-Board-p-1268826.html?rmmds=detail-left-viewhistory__3&stayold=1&cur_warehouse=CN  

 

5W  5V  digital mono. uses the XPT8871 IC (SIMILAR TO LM4871).

Amp has typical 3dB point of ~350 Hz and ~90kHz..  suitable for voice.

 

 10 assembled amps from Banggood for $5.31 USD shipping included.  Amp has typical 3dB point of ~350 Hz and ~90kHz..  

I agree with the use of contemporary component value protocol.  Where 4N70 denotes 4.7nF,  33R0 is 33 ohms, 331 is 330 etc.

73

Re: Inexpensive eBay Amplifier Kits

Lee
 

I have seen some of these come with 30mhz LP filters and some order the model without a filter and add one for the band they will be using.  Is either idea acceptable or is one better than the other.   I just ordered a 70 watt, heat sink, and case on eBay and will have to get a filter. Thank you.
--
Lee - N9LO  "I Void Warranties"

 

Re: RF power chain mods and improvements..

ajparent1/KB1GMX
 

Most of us spend too much on "just a hobby".  I try to be frugal and get the best bang for the buck or whatever.
It is why the junk box to end all is my mainstay.  

Can't solve all the problems, wish I could.  

Allison

Re: uBITX adjustable power supply?

ajparent1/KB1GMX
 

Several things...

Those are switching converters and make noise. 
Some can only go to barely 3A, most much less, the TX will want at least
2+A (at 12V) or more.  At 80m and 24V expect 3 to 3.5A power draw.
I found those I have like that were very weak.  However my bench supply
does it well to 30V and 5A.

The bias stays where its set.

Allison

Re: V4.3 arduino code description... #arduino

ajparent1/KB1GMX
 

Steve, KD1JV has a knack for good code and user interfaces.  I have one of his
short run of Slopbucket SSB/CW 20m rig.  Great radio and very solid user
interface.  Fun build.  The code for it is rather interesting.

I tend to write very bland code.  Lots of lines simple and readable.  I try to
understand what the compiler will create so it can be efficient.

That is why I'm digging deep into the code, to make clean changes and make it 
as I wish it to be.

Allison

Re: Inexpensive eBay Amplifier Kits

Jerry Gaffke
 

Any amateur amp should be followed by a low pass filter suitable for knocking out the second harmonic and beyond.
That means separate filters for 160m, 80m, 40m, 20m, 10m.
You may piggyback some of the other non-harmonic bands into that set of filters,
but that makes the filters much more difficult to design and build.

A rig with only a 30mhz LP filter is likely aimed mostly at CB'rs.

QRP is good for experimenting.
But with a 50W+ ebay amp, you really should be testing for compliance with FCC regs.
It likely fails, and all the nasties will scale up with the output power.

Jerry


On Thu, Jul 19, 2018 at 06:12 PM, Lee wrote:
I have seen some of these come with 30mhz LP filters and some order the model without a filter and add one for the band they will be using.  Is either idea acceptable or is one better than the other.   I just ordered a 70 watt, heat sink, and case on eBay and will have to get a filter. Thank you.
--
Lee - N9LO  "I Void Warranties"

 

Re: uBITX adjustable power supply?

Tom, wb6b
 

That is good information. I haven't load tested the ones I have yet, to see if their rating is honest. They claim to rated rated for 4 amps. Even if I could not go to a full 24 volts, hopefully there would be a worthwhile increase in output power.  Fortunately, if they turn out not to be up to par, they did not cost much and be useful for something else. 

Regarding the noise. If possible, (assuming they can be switched on quickly enough) these would only be running during transmit. So receiver noise should not be a problem. But, did you find any issues with noise causing unwanted transmit emissions?

I was running WSPR with my uBITX. I powered it from a 12V portable battery power box. I discovered that on a few occasions my WSPR beacon was received on two frequencies. The primary and a weaker secondary signal 120HZ away. It seemed to be related to when the battery charger kicked in. So, if the boost converter had significant output voltage ripple or noise, something similar could happen.

Tom, wb6b

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

Mike KK7ER
 

Alas, having the correct version of uBITX Manager did not solve the problem.  Now the CW Side Tone and CW Speed both show as 65535 (0xFFFF).  They are still just as meaningless as before and do not correspond to the values shown on the LCD display.
FYI.

73 Mike KK7ER

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

Tom, wb6b
 

Hi,

This is somewhat puzzling. Assuming it is not a software issue or hardware problem with the USB connection, I'll hazard one guess.

When I looked at the CEC code, some time ago, I noticed a few places, where the CEC firmware was adding new functionally, the code checked to see if the related EEPROM memory address had been set. To maintain backward compatibility with the factory firmware, if it saw 0xFF the code worked in a compatible mode to the factory firmware. 

Have you tried setting the values from the uBITX manager? 

Tom, wb6b

Re: Buying just the stock standard vanilla #Radiuno (no uBitx) #radiuno

VK3HN
 

Thanks Nick, I tried emailing you but didnt hear back.  Email me at vk3hn@... to continue the discussion.

I take it that HFSignals no longer sells just Radiuno by itself?

Re: Buying just the stock standard vanilla #Radiuno (no uBitx) #radiuno

Glenn
 

Paul, I got one from Nick a while back and it works fine as you would expect. Nick put a few extra sections on the PCB which I haven't used. I just dummied one up on the bench yesterday to checkout the CEC Nextion display


.

Re: Buying just the stock standard vanilla #Radiuno (no uBitx) #radiuno

Nick VK4PP
 

Hi Paul, Email replied.
Glenn, Looking good....

Cheers.

Re: RF power chain mods and improvements..

Nick VK4PP
 

Glenn, try minikits.com.au, Great fast service and Genuine parts... Price is acceptable for me.

Cheers.

Re: RF power chain mods and improvements..

Glenn
 

Hi Paul, yes i buy from them also. They don't do the RD06HHF1 device though which I also use.
Their RD16HHF1 is AUD$8.80 (plus postage)   Since i wanted spares etc i elected to buy from RF Parts. Overall price slightly lower.  I have though bought 1 or 2 from Minikits.
glenn

Re: logic mod for filter selection #arduino #ubitx

Nick VK4PP
 

Lovely solution!

Also don't forget about D0 and D1.

73 Nick Vk4PLN

(Some) Nextion Displays not working

Björn Pasteuning
 

I have some Nextion Display (Basic) 2.8" / 3,2" / 4.3"

I Succesfully programmed the 2.8" variant with the firmware of KD8CEC. and works great,
I have also programmed the 3.2" and 4.3" with adapted KD8CEC firmware, and also the firmware of KN4UD
But they both dont communicate with the uBitx

All nextion's where programmed via the serial cable, So I know that port is working ok.

What could be wrong?

 
-- 

73' Björn de PD5DJ
www.pd5dj.nl

Re: uBITX adjustable power supply?

Jim G4GNO
 

Hi Jim
Re. noise,  I am using a 14.8v lithium pack and used of these to drop that to 12volts for the main board (finals stay on 14.8). It was fine for that. Not a trace of noise that i can detect.  The uBitx far outperforms my venerable TS-680 on receive with respect to noise and pretty much everything else in fact.

Jim

 

Re: uBITX adjustable power supply?

Tom, wb6b
 

An additional thought. There is a good chance the rating is honest, but referring to the input current. The output is not isolated so there is no opportunity to run this at 12V out added to the 12V already from the main power source. In that case a beefier boost converter will be needed. I believe Amazon has higher power boost converters for a reasonable price, too. Just not at the impulse buy price these were at. I'll still find uses for these and the buck converters I bough at the same time. They will live happily in my parts box for future use. Load testing will tell what they can do.

Has anyone been able to parallel these and keep the load current equally balanced between them?

Tom, wb6b