Everyone, I have come up with a modification to Gian's circuit that makes the pop/click completely tolerable with headphones at full volume. Please see the attached modified schematic and report back with your results. The pop is still there, but does not tend to hurt the ears. I may get some crap for the layout/design, but I don't care. I am always open to friendly suggestions to make it better.  73 Jonathan, N?JMS
|
Re: Antenna Analyzer problems.
Hi Roy,
I saw very high SWR where I didnt expect one like the original poster. Then in looking at the schematic again of the analyzer I suddenly realized what was happening ! I was uploading the code and running my test from the usb cable so no external power connected. It dawned on me that the analyzer would need external power to function and indeed after connecting a 9V battery it works just fine. Maybe the original poster was also powering the analyzer just from USB if that is the case it might be worth a try to run it of a battery or external power supply,.
regards,
Leo
|
I noticed that later last night (2am) on the M1/M2.. While looking at the drive required for the PTT relay I noticed the RX signal (+12 volt supply to the LM386) is switched by the PTT; Has anyone tried adding a 3.3k resistor to pin 6 of the LM386 and ground?
At any rate I came across K3NG Nano Keyer, I'm changing my layout to use his code.??-- My 'Logic' normally stops around 10PM, that post was past my bedtime! Still waiting on my board.... My layout includes a TCXO for stability, +3 regulator instead of the nano 50ma source and voltage level shift for the Si5351, it does add a couple of dollars.?? ?
|
Re: Bitex40 power output.
Thanks Andy, we'll try what you found.? 73, Karl, KO8S
On Saturday, August 19, 2017 10:16 AM, KM4TRT via Groups.Io <garello@...> wrote:
Hi Karl,
I had the same problem with my 40 and after pulling out the transformer, checking all voltages etc, I found that it was the VFO injection. ?Check the voltages on Q7, Q8, Q9 against the chart. ?I think on mine Q8 was dead.
Andy
KM4TRT
|
Re: Antenna Analyzer problems.
Specifically what issues are you having?
Roy WA0YMH
On Aug 19, 2017 10:58 AM, "Leo de Blaauw" < L.deblaauw@...> wrote: Hi,
Anybody found any solutions or things to trace down the SWR5 problem I am having the same issue it seems...Any help, pointers or tips greatly appreciated.
regards and 73
Leo
|
Re: Antenna Analyzer problems.
Hi,
Anybody found any solutions or things to trace down the SWR5 problem I am having the same issue it seems...Any help, pointers or tips greatly appreciated.
regards and 73
Leo
|
Re: Bitex40 power output.
Hi Karl,
I had the same problem with my 40 and after pulling out the transformer, checking all voltages etc, I found that it was the VFO injection. ?Check the voltages on Q7, Q8, Q9 against the chart. ?I think on mine Q8 was dead.
Andy
KM4TRT
|
That 190mv at C132 might be ok, will depend on audio level going in. I was seeing 400mv pk-pk when applying 100mv pk-pk at the microphone input to the Bitx40: ? ?? /g/BITX20/message/31496In the first link of the above message, I tell how I created a 750 hz 100mv audio signal. You might try adding this line to the end of setup() inside Allard's current Raduino code to create a 7.15 mhz test signal out of the otherwise unused CLK0 from the Si5351: ? ?? si5351bx_setfreq(0, 7150000);Then add a resistor network between CLK0 and C132 to get the RF level at C132 of your choice, see if you can get 5W out of the IRF510. If the voltage at C132 really is too low, there are any number of things between the microphone and C132 that could be attenuating the signal: ?mic amp, modulator, crystal filter, bidi amps, mixer, BPF. The receiver could work quite well even if there was a 10dB attenuation somewhere in there, perhaps due to a cold solder joint on one of the inductors for example. Jerry, KE7ER
On Sat, Aug 19, 2017 at 04:49 am, <jrea79@...> wrote:
at C132 i only got around 190mVp-p, Q13 B is 4.06V, C is 12.93V and E is 3.35V?
so that confirms I have low signal at C132 (It should be 1Vpp right?)
|
Hi Jonathan,
Check the collector of Q7, it should have a 1 - 1.5V p-p flattened sine wave.
Remove C91 and C92 to increase the RF at Q7.
Check the value of R46
toggle quoted message
Show quoted text
At 19-08-2017, you wrote: hi Raj!
I forgot to add that I had R136 at max setting
at C132 i only got around 190mVp-p, Q13 B is 4.06V, C is 12.93V and E is 3.35V
so that confirms I have low signal at C132 (It should be 1Vpp right?)
btw I am using an amplified mic in front of an AM broadcast radio
i also resoldered L1-L3 (removed and re-tinned)
i remember there is a difference between the junction of C11/C41 and C132 - I failed to note and I will get back to it
can you please post also the measurements around Q9-Q7 area?
thanks and 73!
jonathan/DV2NAH
|
Audio volume and distortion fix.
Change the following resistors
R114 from 100K to 220K
R112 from 4.7K to 1K
This will change the biasing to Q16 taking the collector voltage higher and
allowing a larger signal to be amplified without distortion.
Change R111 from 100 Ohms to 10 Ohms, or just piggy back a 10 Ohm.
This Resistor in series with the audio chip is dropping too much voltage at louder
volumes and the sound gets distorted. This mod will give you big volume without
sounding like a torn speaker!
I suggest changing D18 to a 1A diode.
Cheers
--
Raj, vu2zap
Bengaluru, South India.
|
hi Raj!
I forgot to add that I had R136 at max setting
at C132 i only got around 190mVp-p, Q13 B is 4.06V, C is 12.93V and E is 3.35V?
so that confirms I have low signal at C132 (It should be 1Vpp right?)
btw I am using an amplified mic in front of an AM broadcast radio
i also resoldered L1-L3 (removed and re-tinned)
i remember there is a difference between the junction of C11/C41 and C132 - I failed to note and I will get back to it
can you please post also the measurements around Q9-Q7 area??
thanks and 73!
jonathan/DV2NAH
|
First check R141 if the value is more than 10 Ohms change it. Many boards
report failed R141.
At 13.2V DV and 150mV 1Khz audio injection I get
C132 = 1 V p-p
Q13b = 0.6
Q13c = 12V
Preset centered = 1.5V
Preset top = 5V
Q14c no load 20V i.e no Q14 present
Check at the junction of C11 and C41
There is a suspicion that the values of L1,2,3 may not be optimum due
to winding mistakes etc and the filter
may be position wrongly in the 40M spectrum.
Raj
toggle quoted message
Show quoted text
Hello fellow hams!
?
My bitx40 have low output -only about 2 Watts on a dummy load
Originally it has only 1W and the receive is OK
I had checked and rechecked the TX section (Q13-Q15)
All bias voltages are ok, i can adjust for 100mA at Q15 and speaking on
the mic it, only goes to 250-300mA
I also replaced Q13 with 2n3904, rewound T6 and replaced Q15 with no
change. BTW Q13 and Q14 heats up while Q15 is cool.
Using the scope I got the following (all peak to peak):
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?? Base?
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?? ? ? ? ? ? ? ? ? ? ? ? ? ?
?? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?? Collector
Q13? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?? 190mV? ? ? ? ? ? ?
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?
? ? ? ? ?? 1.3V
Q14? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?? 1.9V? ? ? ? ? ? ?
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?
? ? ? ? ? ? ? ? ? ?? 4.4V
Q15? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?? 2.4V (gate)? ? ? ?
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?
?? 10.4V (source)
?
Initially, I suspected Q14 circuit (that?�?s why I rewound T6) and Q15
gate circuit but I found nothing. Are these readings normal or out of
spec?
I went ahead and updated the Arduino to Allard?�?s V1.20.1, made all the
related mods and when I removed C91 and C92 I was surprised that the
output went to 2W on LSB but zero on USB.
I am now thinking that I may have a low VFO signal going to the balance
modulator (is it supposed to be driven with a 1.4V signal?)
At Q7 collector it has 180mV, just a few millivolts on Q8 and Q9 and the
DDS output is only 40mV – all bias voltages are ok
I suspected Q8 since I can only measure a few millivolts on its Base and
emitter but if I short R81 I got 1V at Q7 collector and the output goes
to 3W (even without speaking to the mic) and the receive goes
louder
I disconnected the raduino from the BITX board and measured the output –
it?��?s only around 40mV ( the output drive is set to 8mA) on LSB with
distorted sine wave ? and zero output on USB
Is the Raduino circuit causing the low output power? I am a self-taught
ham and ? I am running out of ideas, any help would be greatly
appreciated, thanks and 73!
Jonathan/DV2NAH
|
Hello fellow hams!
?
My bitx40 have low output -only about 2 Watts on a dummy load
Originally it has only 1W and the receive is OK
I had checked and rechecked the TX section (Q13-Q15)
All bias voltages are ok, i can adjust for 100mA at Q15 and speaking on the mic it, only goes to 250-300mA
I also replaced Q13 with 2n3904, rewound T6 and replaced Q15 with no change. BTW Q13 and Q14 heats up while Q15 is cool.
Using the scope I got the following (all peak to peak):
??????????????????????????????? Base????????????????????? ?????????????? ??????????????? Collector
Q13??????????????????????? 190mV????????????????????????????????????????????????? 1.3V
Q14??????????????????????? 1.9V?????????????????????????????????????????????????????? 4.4V
Q15??????????????????????? 2.4V (gate)????????????????????????????????????????? 10.4V (source)
?
Initially, I suspected Q14 circuit (that’s why I rewound T6) and Q15 gate circuit but I found nothing. Are these readings normal or out of spec?
I went ahead and updated the Arduino to Allard’s V1.20.1, made all the related mods and when I removed C91 and C92 I was surprised that the output went to 2W on LSB but zero on USB.
I am now thinking that I may have a low VFO signal going to the balance modulator (is it supposed to be driven with a 1.4V signal?)
At Q7 collector it has 180mV, just a few millivolts on Q8 and Q9 and the DDS output is only 40mV – all bias voltages are ok
I suspected Q8 since I can only measure a few millivolts on its Base and emitter but if I short R81 I got 1V at Q7 collector and the output goes to 3W (even without speaking to the mic) and the receive goes louder
I disconnected the raduino from the BITX board and measured the output – it’s only around 40mV ( the output drive is set to 8mA) on LSB with distorted sine wave ?and zero output on USB
Is the Raduino circuit causing the low output power? I am a self-taught ham and ?I am running out of ideas, any help would be greatly appreciated, thanks and 73!
Jonathan/DV2NAH
|
Sorry, M1 and M2 are the other way around. Grounding K2.1 shorts the output of the pre-amp Q16 to earth on transmit, leaving the feed to the volume control and U1 open-circuit (and probably picking up hash). If you want to kill that 'pop' in and out of Tx, research back a few messages - I7SWX's circuit is a good start, Ted Doell and I have improved on that, and an earlier (much earlier) solution allows for CW sidetone (possibly also with better stability). Good luck - your 'logic' could use it ...
73
|
Can someone try grounding pin 1 of K2? That will take the input of the LM386 to ground when the PTT is pressed. Now pin 1 of K2 appears to be floating in the schematic I have. I've been working on a PCB to 'clean up' the Raduino some..  ?
|
Ciao Gian,
No worries about the LM386. It still works well. I have spares in the junk box if needed.
I was experimenting trying to discover other methods, and thought I would give what I described a try.
Will keep you posted.
Grazie,
Jonathan, N0JMS
|
Re: Problems with Arduino Nano: has anyone the program for BiTX 40?
?Correction: ? ?Nano has 15 pin positions per side
On Fri, Aug 18, 2017 at 8:15 PM, Larry Smith <815cpu@...> wrote:
?
Most Nanos come with the pins
installed or you need to solder the pins into the Nano
Nano has 30 pins per side and
sometimes the six pin header pin is included.
?
Use the below to search for like
items or order from these sites as shown.
?
New Nanos usually come with the Nano
port - USB cable so you can down load sketches.
?
I program my Nanos not plugged into
the DDS.?
Just make sure the NANO (pins) is
resting on non-conductive surface.
?
I’m sure other members have better parts sources IE ? ?K9AGE
?
I would use pre-cut 15 pin headers as I find
they are a bit tricky to saw…I use a FINE tooth hobby saw.
?
The pins are segmented so small wire
cutter pliers should work.
Make an effort to keep pins and
headers at right angles to the Nano./ DDS PCB.
You can solder a center pin and or
header and check for alignment. Then good to go-solder all. Check for solder bridges
etc..
?
If you’re not sure about this
procedure- note the component side and place a mark denoting the USB port for Nano
insertion.
?
And finally I write the version # on
a self-stick Dot? This way I know what
sketch I downloaded into the Nano .? I have
about 4 Nanos floating around on my desk so I try to keep from confusing
myself.? Otherwise just boot the Nano and
DDS will tell all.
?
copy and paste this Ebay item number
should show Header pins
?eBay item number:
171686744816
?
?
copy and paste this
Ebay item number and it should show the headers:
eBay item number:
292149896446
?
NANO IO Expansion Board +400 Point
Breadboard+120Pcs Jumper Wires Male/Female
copy and paste this
Ebay item number and it should show the headers:
eBay item number:
282608752030
I show and used more
wires on the LCD than are needed,.,to ?lazy to make more efficient for now.
I encourage you to
shop around and I like free shipping :)
I’m almost
certain many BITX’ers know of better sources.
73
Larry
WA9DOH
|
Re: I'm sure it is my hork up re: tft.setFont()
#w8tee
That's not your fault. Starting with Rel 1.8 of the compiler, they tightened up the expression parser to catch more errors that before. Also, the mcufriend library inherits a lot of its functionality from the Adafruit libraries that the code uses. So you need to make sure that you have that library installed.
#include <Adafruit_GFX.h> ? ? // https://github.com/adafruit/Adafruit-GFX-Library
If you look in that library around line 85 you'll see the function prototype for setFont(). If you look at line 13 in the mcufriend header file, you'll see:
class MCUFRIEND_kbv : public Adafruit_GFX {
What this says is that the mcufriend library "inherits" the functionality of the Adafruit_GFX library, but adds some of its own stuff on top of that. So if you see an error that something is missing, it could be that you didn't install the Adaruit library.
Jack, W8TEE
?
From: Vince Loschiavo <vince320@...>
To: [email protected]
Sent: Friday, August 18, 2017 4:55 PM
Subject: [BITX20] I'm sure it is my hork up re: tft.setFont() #w8tee
Jack, not really a programmer.. started to compile got through the MorseCode.h issue, it balks complaining?
Arduino: 1.6.9 (Windows 10), Board: "Arduino/Genuino Mega or Mega 2560, ATmega2560 (Mega 2560)"
?
I:\B40Software\B40SoftwareRel0106\B40SoftwareRel0106.ino: In function 'void ShowFrequency(long int, int)':
?
B40SoftwareRel0106:857: error: 'class MCUFRIEND_kbv' has no member named 'setFont'
?
? ?tft.setFont(); ? ? ? ? ?// Return to default size
?
? ? ? ?^
?
exit status 1
'class MCUFRIEND_kbv' has no member named 'setFont'
?
This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.
I checked in MCUFRIEND_kbv-master\TFT_HX8347GLUE.h and at
line 110 it exists..
could you give a hint? on where I am messing up?
Vince
|
Re: A little ardunio help
On Fri, Aug 18, 2017 at 11:49 am, pat griffin wrote:
I am on the road so I can't verify this but I think you actually must have the compiler connected to some version of the arduino for the code to compile.
I compile stuff all the time without an Arduino connected. Make sure you're clicking on the compile/verify icon in the IDE (checkmark in the upper left corner). ? -- John - WA2FZW
|
Re: Problems with Arduino Nano: has anyone the program for BiTX 40?
?
Most Nanos come with the pins
installed or you need to solder the pins into the Nano
Nano has 30 pins per side and
sometimes the six pin header pin is included.
?
Use the below to search for like
items or order from these sites as shown.
?
New Nanos usually come with the Nano
port - USB cable so you can down load sketches.
?
I program my Nanos not plugged into
the DDS.?
Just make sure the NANO (pins) is
resting on non-conductive surface.
?
I’m sure other members have better parts sources IE ? ?K9AGE
?
I would use pre-cut 15 pin headers as I find
they are a bit tricky to saw…I use a FINE tooth hobby saw.
?
The pins are segmented so small wire
cutter pliers should work.
Make an effort to keep pins and
headers at right angles to the Nano./ DDS PCB.
You can solder a center pin and or
header and check for alignment. Then good to go-solder all. Check for solder bridges
etc..
?
If you’re not sure about this
procedure- note the component side and place a mark denoting the USB port for Nano
insertion.
?
And finally I write the version # on
a self-stick Dot? This way I know what
sketch I downloaded into the Nano .? I have
about 4 Nanos floating around on my desk so I try to keep from confusing
myself.? Otherwise just boot the Nano and
DDS will tell all.
?
copy and paste this Ebay item number
should show Header pins
?eBay item number:
171686744816
?
?
copy and paste this
Ebay item number and it should show the headers:
eBay item number:
292149896446
?
NANO IO Expansion Board +400 Point
Breadboard+120Pcs Jumper Wires Male/Female
copy and paste this
Ebay item number and it should show the headers:
eBay item number:
282608752030
I show and used more
wires on the LCD than are needed,.,to ?lazy to make more efficient for now.
I encourage you to
shop around and I like free shipping :)
I’m almost
certain many BITX’ers know of better sources.
73
Larry
WA9DOH
On Fri, Aug 18, 2017 at 3:56 PM, John D (gmail) <1practical.man@...> wrote: Larry
Can you point me to a source of the headers and ribbon cable you used?
I am very new to all this. I would like to try your approach for easier modularity?
Thanks John? On Aug 18, 2017, at 16:39, Larry Smith < 815cpu@...> wrote: For what it's worth..I have down loaded my DDS pictures with the Nano removed.? I installed headers so I can Plug n' Play nano's as improvements come in.? Just remember the USB connection on the NANO points off the DDS as always (after you solder in the headers). Hope this helps along with the other BITX Group help/ suggestions. The extended LCD display is something I'm trying out. You should be able to zoom these pictures
73 Larry WA9DOH
<032617 1 Nano removed Componet side frm DDS.JPG>
<032617 1 Nano removed frm DDS.JPG>
<032617 2 Nano removed frm DDS.JPG>
<032617 3 Nano removed solder side DDS.JPG>
<032617 Nano removed frm DDS.JPG>
<042717 DDS plugable.JPG>
|
Kevin
Raj vu2zap