Re: boosting the power on 28 MHz
#ubitx
Thanks for the help, Nick.? I think I will wait until Allison works out the flat power output problem.? 15 meters is my favorite band.
73, WA9PWR
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jack, I've seen rigs like yours burn just like that and they were commercially built. don't feel so bad. it happens to us all eventually.
73s david ka9koj ?
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?
Sent from Yahoo Mail. jerry,
you are right a gnd is a ground all the way around. yes the fuse will help on providing a path, but like i said , i would protect it before the fuse because I've worked in the consumer electronics field for 25 years and all the mis wired units I've worked on, was fried. yes a schottky diode is good, . I've seen zeners being used, triacs,optic isolators and other components. but why make it more complicated. some will put a fuse in and throw away the diode to their junk box for another project.some will just use an onboard inline fuse while others may opt for only a diode in series with the hot lead to the switch. and if I'm going to protect my equipment,i use one before the fuse. yes the diode will short out or burn open.ive seen both. and me personally , i wouldn't take the chance to have a positive voltage on my ground plane. a ground is a ground like u said and if any chips or gets on the board are sensitive to a very very brief surge of positive voltage where its supposed to be negative,well i don't want to replace all my equipment I've had for over 35 years since 1980. I've been doing it ever since.yes the diagram is representative of the on/off switch on the audio board. i didn't use that. i installed a toggle switch near the entry point where the source comes in. that way any noise that may be induced into other circuits by running the longer wires are eliminated.And I've seen diodes burn open and the fuse never blew and the fellow hooks it back up the same way and its toast.because the diode is now open and cannot prevent + voltage to ground .that is why i install polarity protection outside of my rigs before the fuse. i don't trust components. 
anyway good discussion. this my own preference of doing things jerry. your suggestions are valid and on the mark. others will think I'm a crackpot. but if you ever seen ebay filled with $500 or higher rigs where the op hooked up the wrong polarity? those units should protect from that but a lot are lacking due to the designs. no matter how much the rig is worth.
anyway ?good info and hope to work you on the bands sometime.
73s,
david todd ka9koj
i
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Re: ND6T AGC implementation for uBIT-X
I believe Kees is kitting these up for 0805 parts.
The 0805 parts are included with his kit.
An 0805 is 0.08 inches long, 0.05 inches wide.
Rational countries use metric numbers to identify surface mount part sizes.
??
?
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On Wed, May 23, 2018 at 10:53 pm, ohwenzelph wrote:
Should the caps and resistors all be 1206 size?
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Re: toggle for low output and max output?
#ubitx
On a somewhat related note, that code of post 44278 conforms with the stock uBitx firmware
in that it keeps the BFO on the low side of the 12mhz crystal filter.
This was done to avoid having audio beat notes between harmonics of?
the 16mhz Nano resonator and the 12mhz BFO.
Playing with my Nano, I don't hear any nasty audio with a high side BFO.
The 16mhz resonator is well away from 16.000 mhz, as it's not terribly accurate.
The 12mhz resonator on the CH340 chip is not active unless cabled up to?
a host computer's USB port.? Convenient, as the 16mhz resonator is the?
only one that is accessible once the Nano is soldered down.? And if one wishes
to communicate with the Nano from a host while using the radio for digital modes,
could use something like the CP2102 of post 50027 if the CH340 is causing grief.
Anyways, might be a good idea to reconsider using a high side clk1 into the second mixer,
always parked at 45mhz+12mhz=57mhz.? Currently it flips between 45-12=33mhz
and 57mhz to select lower sideband and upper sideband operation respectively.
A high side clk1 is preferred, as this will greatly reduce the number of lower frequency
mixer products, and thus reduce the birdie count.?
Though some might prefer to?keep the BFO on the high side of the 12mhz filter.
Crystal ladder filters tend to have a steeper skirt on the upper freq side than on the lower freq side.
? ??
Having the BFO on the upper side improves suppression of the carrier and opposite sideband.
If audio tones from the 16mhz resonator are an issue with some Nano's, a solution might
be to add some capacitance around the resonator to lower the frequency a few khz.
Small caps to ground from ATMega328P pins 7 and 8 where the resonator is wired
should help, but that would be a tricky soldering job for some.
Sticking a finger in there will mess with the resonator considerably,?
a bit of kapton tape and some grounded copper foil should be able to do the same job.?
Better yet, replace the resonator with a crystal of somewhat different frequency??
Or clock the ATMega328P from the BFO, assuming the processor can power up
using some other clock?
Jerry
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On Wed, May 23, 2018 at 10:38 pm, Jerry Gaffke wrote:
There are 2 pole and 4 pole variants of that 45mhz crystal filter.
HFSignals is probably using the 2 pole.
If this method of transmitter attenuation is to be used,?
would be best to keep using the same filter.
Looking at the half dozen lines of code here:
? ??/g/BITX20/message/44278
the 45mhz transmit attenuator feature could be implemented by adjusting the value
of c45 during transmit, then returning c45 to its default value during receive.?
Recompute and reload clk1 and vfo into the si5351 with each transition, the bfo can remain fixed.
Will likely be necessary to calibrate each rig once for constant power across bands.
This could be fully automated if there were a diode RF probe on A7
watching the antenna port into a dummy load.
Jerry, KE7ER
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Re: ND6T AGC implementation for uBIT-X
Should the caps and resistors all be 1206 size?
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Re: toggle for low output and max output?
#ubitx
There are 2 pole and 4 pole variants of that 45mhz crystal filter. HFSignals is probably using the 2 pole. If this method of transmitter attenuation is to be used,? would be best to keep using the same filter. Looking at the half dozen lines of code here: ? ?? /g/BITX20/message/44278the 45mhz transmit attenuator feature could be implemented by adjusting the value of c45 during transmit, then returning c45 to its default value during receive.? Recompute and reload clk1 and vfo into the si5351 with each transition, the bfo can remain fixed. Will likely be necessary to calibrate each rig once for constant power across bands. This could be fully automated if there were a diode RF probe on A7 watching the antenna port into a dummy load. Jerry, KE7ER
On Wed, May 23, 2018 at 10:08 pm, John wrote:
I have uploaded the latest version of my variation on Ian's software with a default of "stock standard" which means it should run on units "factory" wired.
It includes the "OPTION_ALC" where I use a table and interpolation to set the attenuation for? 3 levels (Low, High, Max) for SSB power output.
Not a complex code at all (just search for the "option_alc" keywork). Will give up to around 50dB of attenuation. So should be plenty to control the power even for WSPR low power fans.
I even had to attenuate the signal for "Max" power on 40 and 80m otherwise I would get well passed the targeted 16-17W on the lower frequencies.
But still well short on 10m, so I am following Allison's work on the power chain with great interest.
73, John (VK2ETA)
Software at: /g/BITX20/files/Variations%20on%20KD8CEC%20Software%20%28by%20VK2ETA%29%20+%20ATU%20sketch/uBitx-Raduino-KD8CEC%20based-VK2ETA-Variation%20-%20V20180524.zip
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Re: W8TEE vft/tft questions
There are some encoders that do put out 4 pulses (two sets of A & B pulses) per detent.?
This has been discussed before.? The fix was to make the code swallow two pulses and
use the other 2 pulses.?
Arv
_._
On Wed, May 23, 2018 at 9:00 PM, Jack Purdum via Groups.Io <jjpurdum@...> wrote:
It appears that your encoder sends out 4 pulses on each detent. I'm not where I can test the code, but try something like this:
void SetEncoderDirection() {
? ? encoderDirection = 0;
???? ????newPosition = rotary.read(); ??? if (newPosition == 0) ??????? return;
?? while (count < 4) {??????? // Ignore 3 readings
? ????newPosition = rotary.read();
?? ?? if (newPosition != oldPosition) {
? ? ? ?? if (newPosition > oldPosition)
? ? ?????? encoderDirection = 1;
? ?????? else
? ? ????? encoderDirection = -1;
? ????? oldPosition = newPosition;
}
The idea is to throw away all but the last direction read. Like I said, you'll need to play with it. Also, it will be easier to read your debug code if you don't put things on a new line. Use something like:
#ifdef DEBUG
?if (newPosition != oldPosition) {
? ? ?Serial.print("In SetEncoderDirection old = " );
???? Serial.print(oldPosition);????????????????????????????????????????// No newline here
? ?? Serial.print("?? new = " );
???? Serial.println(newPosition);
?}??????????????????????????????????????????????????????? // Move this one from here....
#endif
If DEBUG is #defined at the top of the file, the debug statements are compiled into the sketch. Comment the #define DEBUG line, and they are no long in the executable, but still can be turned on again if need be.
Jack, W8TEE
Hi Jack, thanks for answering. I have been watching the debug code you mentioned, and the output has changed since things went south. I added some Serial.print statements of my own.? After watching the debug output for a while, I wanted to know what was going on in SetEncoderDirection:
void SetEncoderDirection() {
? encoderDirection = 0;
? newPosition = rotary.read();
?if (newPosition != oldPosition) {
? ? ?Serial.print("Old: " );
? Serial.println(oldPosition);
? ?Serial.print("New: " );
? Serial.println(newPosition);
?}??????????????????????????????????????????????????????? // Move this one from here....
? if (newPosition != oldPosition) {
? ? if (newPosition > oldPosition)
? ? ? encoderDirection = 1;
? ? else
? ? ? encoderDirection = -1;
? ? oldPosition = newPosition;
? }
} ...and also here, at the top of your debug block:
#ifdef DEBUG?
?Serial.print("Direction: " );
? Serial.println(encoderDirection);? ? ? ? ?
Serial.print("Examine Fast Tune: Start = ");? ? ? ? // May be useful for setting Fast Tune rate
Serial.print(fasttuneStart);
Serial.print("? ?end = ");
Serial.print(fasttuneEnd);
Serial.print("? diff = ");
Serial.println(fasttuneEnd - fasttuneStart);
#endif? With this in place, I turned the encoder one detent stop, and you see that SetEncoderDirection was called three times.? I kept doing this, slowly, and you can see from the serial monitor output below that even though I am turning the encoder int he same direction, the encoderDirection is variously 1 and -1.? Every 3rd turn the frequency is just not updated at all, but with the vacillating encoderDirection, the freq. goes up 100Hz and down 100Hz.? I thought maybe a bad solder connection was causing a kind of "echo" in the circuit, so I re-flowed the solder to pins 18, 19 and 20.? I have tried a couple of encoders with the debounce caps installed (but who knows, maybe I have a drawer full of bad ones).? I was reading your followup article on encoders and when I got to the end where you suggest always to look for the last thing you think might be wrong, I even changed the connection wires.? Last thing? that I can think of is to swap out the Arduino mini, which I will get to in a day or so (ugh, all those header pins to solder).? If you can suggest anything else, let me know.? Serial output follows: First turn here:
Old: -1
New: 0
Old: 0
New: -1
Old: -1
New: 0
Direction: 1
Examine Fast Tune: Start = 3324? ?end = 11398? diff = 8074
Old: 0
New: -1
Old: -1
New: 0
Old: 0
New: -1
Direction: -1
Examine Fast Tune: Start = 11539? ?end = 31281? diff = 19742
Old: -1
New: 0
Old: 0
New: -1
Old: -1
New: 0
Direction: 1
Examine Fast Tune: Start = 31422? ?end = 40482? diff = 9060
Old: 0
New: -1
Old: -1
New: 0
Old: 0
New: -1
Direction: -1
Examine Fast Tune: Start = 40623? ?end = 48869? diff = 8246
Old: -1
New: 0
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Re: toggle for low output and max output?
#ubitx
I have uploaded the latest version of my variation on Ian's software with a default of "stock standard" which means it should run on units "factory" wired.
It includes the "OPTION_ALC" where I use a table and interpolation to set the attenuation for? 3 levels (Low, High, Max) for SSB power output.
Not a complex code at all (just search for the "option_alc" keywork). Will give up to around 50dB of attenuation. So should be plenty to control the power even for WSPR low power fans.
I even had to attenuate the signal for "Max" power on 40 and 80m otherwise I would get well passed the targeted 16-17W on the lower frequencies.
But still well short on 10m, so I am following Allison's work on the power chain with great interest.
73, John (VK2ETA)
Software at: /g/BITX20/files/Variations%20on%20KD8CEC%20Software%20%28by%20VK2ETA%29%20+%20ATU%20sketch/uBitx-Raduino-KD8CEC%20based-VK2ETA-Variation%20-%20V20180524.zip
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Re: toggle for low output and max output?
#ubitx
I use a mini train troggle 3pdt on-off-on multi 2 pole switch for this.
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Hihi Sam, ha the universal cure...cheers then. In between two glasses of the beverage you could try to load the test software if you feel so inclined and see if the other Raduino inputs are working. Since the tests are via the serial monitor you don't need working display or inputs. If you are lucky and the other inputs are ok you could re-assign the push button to another input as a (temporary) patch. Test software at? /g/BITX20/files/uBitx%20Diagnostic%20software%20by%20VK2ETAAll the best, 73, John (VK2ETA)
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I did that. It seems like it's taking and reboots at completion. Top line flashes ubitx .20 and disappears. Bottom line says c 1.061 and stays.?
On Wed, May 23, 2018, 8:10 PM kj6etl < pa1zz@...> wrote: Pull the board and remove the display, then try reloading the software. If you are on a Mac you might want to try a PC or Linux. For me the new iMac USB 3.0 ports did not connect and the older MB Pro crashed hard when connecting the arduino. As a last resort I pulled an old laptop from the trash and put Ubuntu on it and was able to load the software.
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Pull the board and remove the display, then try reloading the software. If you are on a Mac you might want to try a PC or Linux. For me the new iMac USB 3.0 ports did not connect and the older MB Pro crashed hard when connecting the arduino. As a last resort I pulled an old laptop from the trash and put Ubuntu on it and was able to load the software.
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Re: boosting the power on 28 MHz
#ubitx
No, you need to cross over the legs... see here:?
73, VK4PLN
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Re: W8TEE vft/tft questions
It appears that your encoder sends out 4 pulses on each detent. I'm not where I can test the code, but try something like this:
void SetEncoderDirection() {
? ? encoderDirection = 0;
???? ????newPosition = rotary.read(); ??? if (newPosition == 0) ??????? return;
?? while (count < 4) {??????? // Ignore 3 readings
? ????newPosition = rotary.read();
?? ?? if (newPosition != oldPosition) {
? ? ? ?? if (newPosition > oldPosition)
? ? ?????? encoderDirection = 1;
? ?????? else
? ? ????? encoderDirection = -1;
? ????? oldPosition = newPosition;
}
The idea is to throw away all but the last direction read. Like I said, you'll need to play with it. Also, it will be easier to read your debug code if you don't put things on a new line. Use something like:
#ifdef DEBUG
?if (newPosition != oldPosition) {
? ? ?Serial.print("In SetEncoderDirection old = " );
???? Serial.print(oldPosition);????????????????????????????????????????// No newline here
? ?? Serial.print("?? new = " );
???? Serial.println(newPosition);
?}??????????????????????????????????????????????????????? // Move this one from here....
#endif
If DEBUG is #defined at the top of the file, the debug statements are compiled into the sketch. Comment the #define DEBUG line, and they are no long in the executable, but still can be turned on again if need be.
Jack, W8TEE
On Wednesday, May 23, 2018, 6:13:07 PM EDT, tom.mccobb@... <tom.mccobb@...> wrote:
Hi Jack, thanks for answering. I have been watching the debug code you mentioned, and the output has changed since things went south. I added some Serial.print statements of my own.? After watching the debug output for a while, I wanted to know what was going on in SetEncoderDirection:
void SetEncoderDirection() {
? encoderDirection = 0;
? newPosition = rotary.read();
?if (newPosition != oldPosition) {
? ? ?Serial.print("Old: " );
? Serial.println(oldPosition);
? ?Serial.print("New: " );
? Serial.println(newPosition);
?}??????????????????????????????????????????????????????? // Move this one from here....
? if (newPosition != oldPosition) {
? ? if (newPosition > oldPosition)
? ? ? encoderDirection = 1;
? ? else
? ? ? encoderDirection = -1;
? ? oldPosition = newPosition;
? }
} ...and also here, at the top of your debug block:
#ifdef DEBUG?
?Serial.print("Direction: " );
? Serial.println(encoderDirection);? ? ? ? ?
Serial.print("Examine Fast Tune: Start = ");? ? ? ? // May be useful for setting Fast Tune rate
Serial.print(fasttuneStart);
Serial.print("? ?end = ");
Serial.print(fasttuneEnd);
Serial.print("? diff = ");
Serial.println(fasttuneEnd - fasttuneStart);
#endif? With this in place, I turned the encoder one detent stop, and you see that SetEncoderDirection was called three times.? I kept doing this, slowly, and you can see from the serial monitor output below that even though I am turning the encoder int he same direction, the encoderDirection is variously 1 and -1.? Every 3rd turn the frequency is just not updated at all, but with the vacillating encoderDirection, the freq. goes up 100Hz and down 100Hz.? I thought maybe a bad solder connection was causing a kind of "echo" in the circuit, so I re-flowed the solder to pins 18, 19 and 20.? I have tried a couple of encoders with the debounce caps installed (but who knows, maybe I have a drawer full of bad ones).? I was reading your followup article on encoders and when I got to the end where you suggest always to look for the last thing you think might be wrong, I even changed the connection wires.? Last thing? that I can think of is to swap out the Arduino mini, which I will get to in a day or so (ugh, all those header pins to solder).? If you can suggest anything else, let me know.? Serial output follows: First turn here:
Old: -1
New: 0
Old: 0
New: -1
Old: -1
New: 0
Direction: 1
Examine Fast Tune: Start = 3324? ?end = 11398? diff = 8074
Old: 0
New: -1
Old: -1
New: 0
Old: 0
New: -1
Direction: -1
Examine Fast Tune: Start = 11539? ?end = 31281? diff = 19742
Old: -1
New: 0
Old: 0
New: -1
Old: -1
New: 0
Direction: 1
Examine Fast Tune: Start = 31422? ?end = 40482? diff = 9060
Old: 0
New: -1
Old: -1
New: 0
Old: 0
New: -1
Direction: -1
Examine Fast Tune: Start = 40623? ?end = 48869? diff = 8246
Old: -1
New: 0
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Re: boosting the power on 28 MHz
#ubitx
What is the difference in the pads for the RD16HHF1 versus the IRF510?? Can i directly replace the IRF510 with the RD16HHF1?
Bill
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Re: RF power chain mods and improvements..
My brassboard is basically like the ubitx save for it has a lot of scarce parts
that do it well.? ?The interstage transformers were using BN43-202/43-302
up to the fets and went with BN43-3312 because i have a few.? For 10W
is a lot bigger than needed.? Transistor line up had a pair of mrf449s as driver
and a single 2SC779 for -predriver.? The first amp was a 2n2369A.? Most of those
if you find them are not cheap or counterfeit.? I got them way back as they?
were once cheap as common for CB radio driver and finals.
At one point the finals wer MRF137Y (15W gemini two on a single header good to 400mhz)
as I have some, killer part if you have 24V kinda weak at 12V.? The IRF510s were better
at 12V.? That the real issue with all the good LDMOS fets they want 28,? 36, or 50V
but they perform.
On the mixers the best (max) output is usually about 10db below the LO power.
More than that your into gain compression to some amount.? I have not measured
the mixer drive but if its 10dbm its more than I'd guess.? So that is where I pulled
that number from.?
Allison
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Re: RF power chain mods and improvements..
Nick,
That's good as then there are two like this.? ?I'm testing mine.??
I have one report of the MPSH10s might be a bit tepid in their power handling.
The might work for the predriver and not well in the driver.? Its why we build and test.
I've built a lot of amplifiers for many of my radios so this problem is one not unfamiliar to me.
Especially as I've done it from HF through 2M and a few higher power amps for 432.
To get the power wanted you must have the gain and the gain has to hold across the?
band of frequencies.? For example I can get 2n3904s to be flat to to 30mhz,? Run all
of the stages at a gain of 10DB? we would need one more stage than is in the BITx
and we are good but its not eh best way to go and ot would be hard to add/mod.
Allison
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Re: RF power chain mods and improvements..
Hi Allison, thanks. My little proto board is from Q90 to the FET pre drivers. See below, the PCB on left side. OK on the -10dBm level. Will use that in any future testing, once i get the 2N4427's etc installed.? Not likely today as other commitments here. glenn 
On Wed, May 23, 2018 at 06:52 pm, ajparent1/KB1GMX wrote:
First off the output of the mixer is anywhere near -6dbm its going to be distorted.
I'd expect -10dbm max.
The mpsh10s I have not tried as they have not arrived.? I'd expect to have to pair them up
as their power handling is about par with 2n3904s.
Also my test includes the q90, predrier and driver that should be over 44DB of gain
or you will never make enough power to make the IRF510s run.
The 3866s had the existing bias.? Also I have all of the peaking suggestion in place.
Allison
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Re: RF power chain mods and improvements..
I think they might work.? If you got them smoke them (hopefully not).? I don't have enough 5109s
or 4427s to try.
Allison
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kj6etl
Nick VK4PP