Date   
Re: RD16HHF1 power curve flattening...some

John <passionfruit88@...>
 

Hello Nick,

This looks like a good result.

Just to summarise your changes: RD16 finals, BN43-3312  1T primary, 2T secondary, 320pf on all 7 emitter resistors of the pre-amp chain, 330pf across the primary of the final's winding. Anything else?

Since I am portable VK4/Brisbane area at present we could try a QSO if you want. We should be able to get 20m going as we are far enough from each other.

All the best,

73, John (VK2ETA)

Re: uBITX AM BCI Filter (3.5mhz High Pass Filter) #ubitx

Jerry Gaffke
 

Hmmm, a stopband below 1705khz, passband above 1800khz.
Possible, and worth looking into for the few interested in operating on 160m.

But given the same number of parts, designing for a passband above 3.5mhz
will give much better results.


On Sat, Mar 31, 2018 at 04:32 pm, K9HZ wrote:
Nick, Just curious… there is a ham band that u cut out between 1.8-2.0 MHz with this filter.  I think the board is super but maybe start the band pass at 1.8?

Re: #ubitx Progressive 50dB+ Software based RX (and TX) IF attenuation. #ubitx

Jerry Gaffke
 

The crystal filters are not quite aligned when using the standard firmware
as per this post:  https://groups.io/g/BITX20/message/44278
A somewhat related post is this:  https://groups.io/g/BITX20/message/44515

Curious that John in post 45675 was not noticing a change in audio quality, just signal strength.

Jerry


On Sat, Mar 31, 2018 at 06:33 pm, John wrote:
Me too I noticed that the two filters are not quite aligned as defined by the factory setting,

Re: Arduino For Idiots?

Stephen Wandling
 

For now, I have purchased a $3 Canadian Kindle:

https://www.amazon.ca/dp/B079R94QBV/ref=pe_386430_122412850_TE_DP

Then for $10 Canadian Arduino Nano, shipped:

https://www.amazon.ca/dp/B01FV7NIUA/ref=pe_3034960_233709270_TE_item

Thanks for all of the advice.  I have noted all of the book suggestions, for when my skill level rises.  I am feeling less lost already. 

Stephen

VE7NSD


Re: RD16HHF1 power curve flattening...some

Nick VK4PP
 

Hi John,
BN42-202, but a 2:4 ratio winding giving 1:4 transformation. Runs cool at 20+w with 330pf Mica cap. 220ohm feedback resistor.
Listening on 14.277 ?
73 Nick

Re: RD16HHF1 power curve flattening...some

John <passionfruit88@...>
 

Thanks Nick for the information.

Calling now on 14,277.

73, John (VK2ETA)

Re: RD16HHF1 power curve flattening...some

Ashhar Farhan
 

How much power should we put out? It is really your call. I personally prefer 10 watts. There are multiple reasons. First, between 10 watts and 20 watts, the other side will feel almost no difference. Second, at 10 watts, I can still you batteries. Third, the heatsink is managable. Fourth, I am technically in QRP land.

- f


On Sunday 01 April 2018 09:03 AM, Nik VK4PLN wrote:
Hi John,
BN42-202, but a 2:4 ratio winding giving 1:4 transformation. Runs cool at 20+w with 330pf Mica cap. 220ohm feedback resistor.
Listening on 14.277 ?
73 Nick

Re: uBITX AM BCI Filter (3.5mhz High Pass Filter) #ubitx

Nick VK4PP
 

Hi all.
for a 1.7mHz cut off try these:  4.207nF - 3.754uH  - 1.039nF - 2.341uH - 1.039nF - 3.754uH - 4.207nF 

3.75uH is 35 turns on a T37-6 (T30 will be too small)
2,34uH is 28 turns.

Good luck.
73.

Re: RD16HHF1 power curve flattening...some

Gordon Gibby <ggibby@...>
 

I'm VERY impressed and interested in the ability to have up to 20W for these reasons:


1)  I see this as a way to entice many local ARES club members into moving into HF from their exile in VHF-only land....20 watts  possibility is quite useful.

2)  I do mostly digital, so I set the power level by adjusting the TX GAIN on the Signalink (or more likelly, on the homebrew interface I soldered together)​ -- so I can easily set it at a modest 10W if the rig itself can produce up to 20....with the higher duty cycle, this is prudent.

3)  I'd like to get folks locally into an 80 meter training net, and having a rig that can handle up to 20 watts SSB peaks (with its low duty cycle) at this price level is very attractive.   I can honestly tell them they will be doing 8-10 W out from the beginninng on the lower bands, and that they can double that if they wish with a bit of soldering work.


Many of these people learned how to solder only within the last year (from me) and building gas discharge tube lightning arrestors last weekend is the proper level of challenge for them!!!


Cheers,


gordon




From: BITX20@groups.io <BITX20@groups.io> on behalf of Ashhar Farhan <farhanbox@...>
Sent: Saturday, March 31, 2018 11:41 PM
To: BITX20@groups.io
Subject: Re: [BITX20] RD16HHF1 power curve flattening...some
 

How much power should we put out? It is really your call. I personally prefer 10 watts. There are multiple reasons. First, between 10 watts and 20 watts, the other side will feel almost no difference. Second, at 10 watts, I can still you batteries. Third, the heatsink is managable. Fourth, I am technically in QRP land.

- f


On Sunday 01 April 2018 09:03 AM, Nik VK4PLN wrote:
Hi John,
BN42-202, but a 2:4 ratio winding giving 1:4 transformation. Runs cool at 20+w with 330pf Mica cap. 220ohm feedback resistor.
Listening on 14.277 ?
73 Nick

Re: Arduino For Idiots?

Steven Read
 

I am not sure how much you already know about the Arduino & how much you want to know but this appears to be a good starting point 

I am OLD SCHOOL & like to see how to do something rather than read about it until I have built up some proficiency. I do not have a BITX20 but went through this a couple of years ago when my wife got a small robot with an Arduino board in it from RadioShack. Compared to some others the IDE seems a bit primitive by current standards. 

I am assuming putting the BITX20 together will not present any problems or I may just have missed that as I am rushing to get this sent. 

I am typing this on my phone & am a few minutes from it shutting down due to battery. I will check back here regularly to watch for your posts.

Steven Read - ab9ol - (em79jt) Dublin, IN 

--

Steven Read - ab9ol - Dublin, Indiana (em79jt)

Re: #ubitx Progressive 50dB+ Software based RX (and TX) IF attenuation. #ubitx

John <passionfruit88@...>
 

Hello Jerry,

Thanks for the reply. 

Yes I am asking myself the same question (see my previous post looking for a logic gap).

I haven't been able to find an amateur station strong enough to fully test it and I have had to rely on AM broadcast stations for my tests.

I would be great if someone could load the modified software (in the file section) and do a real-life comparison by manually shifting the 1st IF in the presence of S9+20 and over stations.

All the best,

73, John (VK2ETA)

#ubitx #ubitx-help Wow! the ubitx.net/ site is amazing! #ubitx #ubitx-help

D. Daniel McGlothin KB3MUN
 

I had looked over the http://ubitx.net/ site several times earlier in its infancy.

I just now read thru the entire site. It is an impressive aggregation of apparently all knowledge about the uBITX as discussed here since the uBITX release.

I will be building my new uBITX using the http://www.hfsignals.com/index.php/ubitx/ schematics and build info but viewed thru the lens of http://ubitx.net/ .

Thanks, ubitx.net for the work you have put forth in organizing this helpful information.

Daniel KB3MUN

Re: #ubitx #ubitx-help Wow! the ubitx.net/ site is amazing! #ubitx #ubitx-help

Mike Woods
 

Dan

Thanks for the nice thoughts about www.ubitx.net

Hopefully it will help quite a few people along the way to constructing the kit, building a µBITx from scratch, or modifying their pride and joy.

73 Mike ZL1AXG ubitx.net

On 1/04/18 4:51 PM, D. Daniel McGlothin KB3MUN wrote:
I had looked over the http://ubitx.net/ site several times earlier in its infancy.

I just now read thru the entire site. It is an impressive aggregation of apparently all knowledge about the uBITX as discussed here since the uBITX release.

I will be building my new uBITX using the http://www.hfsignals.com/index.php/ubitx/ schematics and build info but viewed thru the lens of http://ubitx.net/ .

Thanks, ubitx.net for the work you have put forth in organizing this helpful information.

Daniel KB3MUN

--
Mike Woods
mhwoods@...

Re: #ubitx Progressive 50dB+ Software based RX (and TX) IF attenuation. #ubitx

John <passionfruit88@...>
 

Puzzle solved by Ian Lee. Thank you Ian.

The issue was that in the fonts in my computer, lowercase "L" and number "1" appear exactly the same. So 1000l (l for Long) reads as 10001.

So my frequency numbers are all too small by a factor of 10.

Here is the corrected graph and it explains why the slope of the filter is not noticeable on the audio since we are introducing about 1dB of impact between 500Hz and 2400Hz when using the slope of the filter.



Now the theory matches the practice..hihi

It also means that the first IF filter is (in my case) around 7000Hz out of alignment with my 2nd IF filter, as mentioned before.

Please note that Ian has released a video of the 1st If shift. See  https://youtu.be/QcOs_gzg-_8

I will correct and re-upload the test sketch as well.

All the best,

73, John (VK2ETA)

Re: Arduino For Idiots?

Stephen Wandling
 

Steven, yesterday I knew nothing about Arduino.  I know a bit more after reading the first bit of the Kindle I mentioned.  How much I want to know, is a question that is premature for me. 

I was looking for some peace of mind, and if I bought a BITX, I did not want to be stepping into a 'world' that would require 'extensive' education on my part.  If that were the case, I would probably not buy the BITX.

Once I begin working my my Nano, I may decide I need to take my Arduino up a notch, or not.  And with the BITX I suspect it will be much the same.  If I REALLY want a feature, I would learn how to make it happen.

I am closer to 80 than to 75 and serious education is not usually on my horizon.  While I often watch a Youtube on some topic, just to get the general idea of how things are done, I value having time to think when I read.

Stephen

VE7NSD


On 3/31/2018 8:53 PM, Steven Read wrote:
I am not sure how much you already know about the Arduino & how much you want to know but this appears to be a good starting point 

I am OLD SCHOOL & like to see how to do something rather than read about it until I have built up some proficiency. I do not have a BITX20 but went through this a couple of years ago when my wife got a small robot with an Arduino board in it from RadioShack. Compared to some others the IDE seems a bit primitive by current standards. 

I am assuming putting the BITX20 together will not present any problems or I may just have missed that as I am rushing to get this sent. 

I am typing this on my phone & am a few minutes from it shutting down due to battery. I will check back here regularly to watch for your posts.

Steven Read - ab9ol - (em79jt) Dublin, IN 

--

Steven Read - ab9ol - Dublin, Indiana (em79jt)

Re: #ubitx Progressive 50dB+ Software based RX (and TX) IF attenuation. #ubitx

Jerry Gaffke
 

Adding L's to 32 bit constants seems to be a thing with this group.
I doubt it's necessary, even on our Nano under the Arduino IDE where an int is 16 bits.
C compilers can easily determine that they must treat 12345678 as a 32 bit integer, and do so.
They have done so for the last 40 years.
See section "A2.5.1 Integer Constants" in Appendix A (The Reference Manual), in the second edition of K&R C.

My copy of K&R has nothing to say about 64 bit long-longs, however. 
They weren't a thing in 1988.

Jerry, KE7ER



On Sat, Mar 31, 2018 at 10:17 pm, John wrote:
The issue was that in the fonts in my computer, lowercase "L" and number "1" appear exactly the same. So 1000l (l for Long) reads as 10001.

Re: #ubitx Progressive 50dB+ Software based RX (and TX) IF attenuation. #ubitx

John <passionfruit88@...>
 

I just wished they were written as capital L. It would have saved me some head scratching...hihi

73, John

Re: #ubitx Progressive 50dB+ Software based RX (and TX) IF attenuation. #ubitx

John <passionfruit88@...>
 

Corrected code snippets for programmers:


#define OPTION_SMETER
#define OPTION_SOFTWAREAGC


void doSoftwareAGC() {
#ifdef OPTION_SMETER
 
  int newSMeter;
 
  //VK2ETA S-Meter from MAX9814 TC pin
  newSMeter = analogRead(ANALOG_SMETER);
  //Serial.print("newSMeter:"); Serial.println(newSMeter);
 
  //Faster attack, Slower release
  currentSMeter = (newSMeter > currentSMeter ? ((currentSMeter * 3 + newSMeter * 7) + 5) / 10 : ((currentSMeter * 7 + newSMeter * 3) + 5) / 10);
 
  //Serial.print("currentSMeter:"); Serial.println(currentSMeter);
  //Scale it
  scaledSMeter = 0;
  for (byte s = 8; s >= 1; s--) {
    if (currentSMeter > sMeterLevels[s]) {
      scaledSMeter = s;
      break;
    }
  }
  //Serial.print("scaledSMeter, un-adjusted:"); Serial.println(scaledSMeter);
#ifdef OPTION_SOFTWAREAGC
  //Apply auto-shift of first IF to increase the dynamic range of the Audio AGC circuit
  long previousShift = firstIfShift;
  if (scaledSMeter >= 7) {
    //Reduce gain by shifting the first and second If by the same value, thereby
    //  leaving the RX frequency the same but using the slope of the roofing
    //  filter to deliver progressive attenuation.
    // 10kHz or 5kHz per step.
    firstIfShift += (scaledSMeter > 7 ? 10000 : 5000);
  } else if (firstIfShift > 0 && scaledSMeter < 1) {
    //Re-increase the gain if we reduced it earlier
    firstIfShift -= 5000;
    firstIfShift = firstIfShift < 0 ? 0 : firstIfShift;
  }
  if (firstIfShift != previousShift) {
    setFrequency(frequency);
    //Serial.print("firstIfShift:"); Serial.println(firstIfShift);
    //Adjust meter by IF attenuation except for the first 10Khz. Approx 6dB per 5KHz.
    scaledSMeter += (firstIfShift > 10000 ? (firstIfShift - 10000) / 5000 : 0);
    //Serial.print("scaledSMeter, adjusted:"); Serial.println(scaledSMeter);
  }
#endif  //OPTION_SOFTWAREAGC
#endif  //OPTION_SMETER
 
}



//And the setfrequency function becomes:

 
void setFrequency(unsigned long f) {
  f = (f / arTuneStep[tuneStepIndex - 1]) * arTuneStep[tuneStepIndex - 1];
 
  setTXFilters(f);
 
  if (cwMode == 0)
  {
    if (isUSB) {
      //si5351bx_setfreq(2, SECOND_OSC_USB - usbCarrier + f  + (isIFShift ? ifShiftValue : 0));
      si5351bx_setfreq(2, SECOND_OSC_USB  + firstIfShift - usbCarrier + f  - ((isIFShift && !inTx) ? ifShiftValue : 0));
      si5351bx_setfreq(1, SECOND_OSC_USB + firstIfShift);
    }
    else {
      //si5351bx_setfreq(2, SECOND_OSC_LSB + usbCarrier + f + (isIFShift ? ifShiftValue : 0));
      si5351bx_setfreq(2, SECOND_OSC_LSB  + firstIfShift + usbCarrier + f + ((isIFShift && !inTx) ? ifShiftValue : 0));
      si5351bx_setfreq(1, SECOND_OSC_LSB + firstIfShift);
    }
    //VK2ETA Bring back the BFO to default if using IF Shift and we are TXing
    si5351bx_setfreq(0, usbCarrier + ((isIFShift && !inTx) ? ifShiftValue : 0));
  }
 
  else
  {
    if (cwMode == 1) { //CWL
      //si5351bx_setfreq(2, SECOND_OSC_LSB + cwmCarrier + f + (isIFShift ? ifShiftValue : 0));
      si5351bx_setfreq(2, SECOND_OSC_LSB  + firstIfShift + cwmCarrier + f + ((isIFShift && !inTx) ? ifShiftValue : 0));
      si5351bx_setfreq(1, SECOND_OSC_LSB + firstIfShift);
    }
    else {            //CWU
      //si5351bx_setfreq(2, SECOND_OSC_USB - cwmCarrier + f + (isIFShift ? ifShiftValue : 0));
      si5351bx_setfreq(2, SECOND_OSC_USB  + firstIfShift - cwmCarrier + f - ((isIFShift && !inTx) ? ifShiftValue : 0));
      si5351bx_setfreq(1, SECOND_OSC_USB + firstIfShift);
 
    }
    //VK2ETA Bring back the BFO to default if using IF Shift and we are TXing
    si5351bx_setfreq(0, cwmCarrier + ((isIFShift && !inTx) ? ifShiftValue : 0));
 
  }
 




Variation on Ian's KD8CEC uBitx software (based on his 1.04 release for now) and ATU sketch. #ubitx

John <passionfruit88@...>
 

I have implemented the following changes in this software targeted at /P, /PM operations (software is in the files section):
 
1. Options for various features which can be turned on or off. Key objective is to be able to customise the rig based on your needs and unfortunately on the restricted memory size of the Nano. So not all features can be selected at once. Choices, choices...
 
2. ATU control. A servo-based L-Network ATU. The communication between the Raduino and the ATU Arduino is via I2C. There is a separate sketch for the ATU Arduino (Nano or Pro-mini). ATU operating mode can be set to OFF, Manual as in on-demand, or auto-RX meaning that it pre-tunes based on historical data on a change of band and after first change of dial frequency (for a quick scan of the bands). It uses the EEPROM data of the closest stored frequency for pre-tune or tune on-demand to accelerate the tuning process.
 
3. Handsfree microphone/headphone. Using an Android style 3 rings (TTRS) handsfree earpieces/mic combination, with 1 or 3 buttons (Play/Pause, +, -), the PTT is controlled by Play/Pause as toggle, and I use long presses on + and - as respectively pre-tune and smarttune of the ATU. Short + or - presses could be used for frequency up and down. Requires a very simple hardware mod to free-up A6 (see below).
 
4. SWR measure and display, using analogue input A7 from an 2N7002 based AGC or a MAX9814 circuit or any other for that matter.
 
5. Software based AGC range extender to augment (as in double or triple) the dynamic range of an audio AGC. This uses the slope of the 1st If filter at 45Mhz to attenuate the Rx signal when the audio AGC reaches its limit. Adds over 50dB of dynamic range.
 
6. Forward power and SWR measure and display. Currently assumes that th ATU is providing that info over I2C. Otherwise could be adapted with a pair of analogue inputs for measure. See the excellent NT6D design on the wiki. 
 
7. An option to display the S-Meter, SWR and forward power in either easy to see "fat" bars with no number, or "skinny" bars with more text and numbers.
 
8. An option to enable a "Memory mode", selectable by menu, which cycles through all the populated memories (channels). Dial lock also locks the change of channels.
 
9. Made some rarely used or once-off functions as options to recover program memory after initial tuning and allow for more options to be selected.
 
10. Fixed some issues with the IF-shift option. Ian has resolved these in his new V1.06 and later releases. Two issues were present: IF-shift in USB would change the receive frequency and it was applied to TX as well. Now applies to Rx only.
 
The only required hardware mod is to connect the CW key input to the PTT. Since in Ian's software we select the mode by menu, there is no need to have a separate analogue input tied-up for the CW key. This frees-up analogue input 6 for use by other functions like the handsfree option above.
 
To-Do: apply Ian's improvements in 1.06, especially CW transmit frequency option and if possible the WSPR beacon mode.
 
Usage: download the zip files, unzip in your Arduino sketches folder. Edit the ubitx_20 options sections, using #define for enabled and #undef for disabled. Perform a CTRL-R to compile and check how much memory is used. If you go over the limit, a warning is issued. Upload to the Arduino.

I have uploaded both the Raduino as well as the Arduino sketch for the ATU and SWR measurement. They can be found in the folder "Variations on Ian Lee's Software (by VK2ETA) + ATU sketch".
 
All software in under GPL V3. 
 
All the best,

73, John (VK2ETA)

No More Smoke -- Changes to our podcast

Bill Meara