MOSFETs are just an electronic form of variable resistor.? No need for drain voltage.
_._
On Tue, Nov 7, 2017 at 11:42 AM, Philip Thompson <pcteee@...> wrote: Must be having a senior moment but how does this AGC circuit work when there
is no voltage on the drain of the FET ....
Phil? G4JVF
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Must be having a senior moment but how does this AGC circuit work when there is no voltage on the drain of the FET .... Phil? G4JVF 
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Re: BITX40 build for SOTA/POTA operation
I glued strips of wood just below the lid, then set the plastic face on top of the wood. The extra pot without the knob is just the volume control. I think this is the for $9 from walmart. Added a pic of the antenna auto transformer. Its a 150-43 core with 14ga wire. I could have used a smaller core but this one is light enough for now. The caps are 2 x 120pf 6000v in series. BTW you can use this antenna at low heights for nvis. 
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Re: BITX40 build for SOTA/POTA operation
WalMart has the Shakespeare Wonderpole 20' collapsible rod for $30 ish. ?It works great for me! ?You'll need to figure out guying though.
If you want an end fed half wave, Sotabeams Pico Tuner is 10w rated and very simple to make, but single band. ?While you're ordering, pick up a couple wire winders and a guying ring (If I recall, the 22mm ring works great on the Wonderpole with a bit of electrical tape to bulk up the pole where you want the ring to sit)
If you want a dipole, you can leave the last section of the Wonderpole collapsed - You need the extra rigidity to support the extra weight of the coax.
I second the motion to just get out there. ?Don't let the perfect be the enemy of the good here - I guarantee your setup will change as you find out what you need in the field. ?Fastest way to learn is to just get out there.
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Re: raduino v1.27 released (improved suppression of spurious burst)
Adafruit?just added another option:??Because it's a breakout board, it might be easier to use than a raw DIP chip.?
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Re: raduino v1.27 released (improved suppression of spurious burst)
El 07/11/17 a las 01:58, Mike Woods
escribi¨®:
I am in the process
of adding the following features/mods:
- Multi-banding using the QRP-Labs relay boards (LPF and
BPFs)? ?- Requires 5 digital I/O ports (or 10 if you want to
drive relays directly from a port)
In the actual state of the project/sketch you don't have as much as
5 free ports, I will suggest for version 2 the use of a I2C I/O
expansion board as we already has a I2C bus and the code must be
easy to implement.
If this is the path I will use those I/O ports for Output only and
in non time-critical outputs to make the delays at minimum.
Allard: I have some experience with using the Si5351 for VFO/BFO
from another active project, just let me know when the v2 start to
develop to contribute with ideas/code/tips/etc.
--
73 CO7WT, Pavel.
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Re: uBITX - A reboot of the old BITX
Ashhar,
I want to thank you for the work you are doing and I hope this renews interest in homebrewing ham radio equipment. I am going to build a uBITX and hope to inform you soon about my success.
Art
KB8HGW
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Re: raduino v1.27 released (improved suppression of spurious burst)
Port expansion can be had for a few dollars:?. What about adding a second Nano? Would still be cheaper than upgrading to a SAMD board. Oh, and speaking of digital modes, I've experimented with AFSK decoding (for APRS) on a Nano and it's ADC is just fast enough :)
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Re: raduino v1.27 released (improved suppression of spurious burst)
We've now got over a thousand units in the field. ?
Allard's been creating code for the majority of Bitx40v3 users who don't want a major project
on their hands, they want existing hardware to work better with a minimum of mods.
And he's doing an incredible job of that. ?
Look for the donate button to his favorite charity in his github page if you agree.
But yes, it would be nice for a few of us to move to something bigger than a Nano.
I doubt we will all agree, as we have different goals in mind.
But we should be able to structure things such that we can swap in the various processors and displays available.
Here's a few of the features I would like to see:
? ? Arduino compatible with standard libraries available
? ? ARM 32 bit core, up from the 8 bit ATMega stuff.
? ? 12 bit ADC's
? ? More IO pins, RAM and flash
? ? Cheap
Here's a couple contenders, neither of which I have tried:
? ??
? ??
Moving up to a Teensy3.6 with floating point in hardware would be great for experimenting with digital modes,
but at $30 it might not be the first choice for many users of a $59 radio.
The Arduino world is stuck at 5v for some reason, the ARM processors and most?
peripheral chips that have come out in the last 20 years are at 3.3v.
I would move to a 3.3v i2c display if speed and noise were not issues.
The Raduino with its soldered down Nano hinders this evolution.
But we could glue a small PC board for the si5351 to the back of the Bitx40v3 main board
then we can swap processors and displays at will. ?
Allard's most recent sketch uses a non-standard Arduino library for interrupts to deal?
with the carrier burst, that part of the code should be if-def'ed out so it is easily removed
when using something other than an ATMega processor. ?There are other ways to suppress the
carrier burst.
Jerry, KE7ER
toggle quoted message
Show quoted text
On Mon, Nov 6, 2017 at 10:58 pm, Mike Woods wrote:
My feeling is that it would be good to decide collectively, on where we go with the processor!? ?Choices seem to be:
- Arduino Mega Mini Embed (available from China for around US$8 including headers).? This is functionally the same as a Mega meaning tons of room and ports.
- Maple Mini STM Clone (BAITE) - About US$5 - very affordable and solves headroom problem and it has sufficient extra ports (particularly if the display uses I2C)
- Teensy 3.6 (or earlier) - but about US$30 each.
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Re: BITX40 build for SOTA/POTA operation
On Tue, Nov 7, 2017 at 06:06 am, <quietglow@...> wrote:
but I do have to find a way to operate w/o a tree
Check out W7RLF's solution He is using an L match tuner.? If you are looking for light and easy you might try ? My advise as a master over thinker, stop over thinking it and just get on the air.? The radio will work just fine in the plastic box it shipped in or a cookie tin or whatever as long as you aren't white water rafting or rappelling into the grand canyon.? Hot glue the heck out of everything for extra insurance.? I can almost guarantee you that whatever case/antenna/power/etc... decisions you make you will want to change after using them anyway.? Like Mike Tyson always said, " Everybody has a plan until they get punched in the mouth".? Get on the air before you are waist deep in snow.? Once you figure out what works or doesn't you can build your dream set up.
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Hello, everyone - bitx newbie here. I just got my bitx40 this week and have it wired up for receive while I wait for the next VE exam session. In the mean time I've been looking through the Raduino code as there are several modifications I'd like to try. After getting frustrated with the Arduino IDE, I searched around and discovered PlatformIO. It's pretty nice. I took a stab at reshuffling the Raduino code around to work in PlatformIO:? IMO, the sketch is rather large and would benefit from some refactoring/splitting up. This is not easily done with the Arduino IDE, but relatively straightforward with PlatformIO. It has much nicer way of dealing with libraries. Rather than everything coming from one global libraries folder, you can specify project-specific libraries through configuration: [env:nanoatmega328]
?platform = atmelavr
?board = nanoatmega328
?framework = arduino
?lib_deps =
? ?[email protected]Also in your source tree, you can include your own project-specific libraries (details in this ). So, is this something people would be interested in trying out?
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Raduino firmware upgrade instructions at
73 AL
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Re: BITX40 build for SOTA/POTA operation
I like all these antenna options, but I do have to find a way to operate w/o a tree. The MI parks ask people not to run anything up into trees because of concerns about moving parasites around. I am thinking the tenkara fishing rod option or possibly a magloop. Mag loops seem to get much simpler to build when you're talking QRP power (no vacuum capacitor needed).
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Raj,
thanks a lot, now it compiles too on my Pc,
Der Sketch verwendet 5882 Bytes (19%) des
Programmspeicherplatzes. Das Maximum sind 30720 Bytes.
Globale Variablen verwenden 592 Bytes (28%) des dynamischen
Speichers, 1456 Bytes f¨¹r lokale Variablen verbleiben. Das Maximum
sind 2048 Bytes.
so only 5,8 kB
thanks a lot!!
Am 07.11.2017 um 14:36 schrieb Raj
vu2zap:
toggle quoted message
Show quoted text
Henning,
I added these libs and it compiles as is..
I could not send this to the group so here are the dropbox links
Raj
At 07-11-2017, you wrote:
Michael,
after commenting out the two header files You stated below, I
had to
comment out a lot more lines, then it compiled, only 5 k of
code, see the
attached sketch. But i am not sure if this code will give a
working
result.
I got Your pcb, but have not populated it due to non existing
files i.e.
schematics, layout. I remember You sent it to me but momentarily
I can
not find these files...
Henning
Am 05.11.2017 um 22:06 schrieb Michael Hagen:
Probably these?
#include "si5351.h"
#include <Rotary.h>
Remember the complaint the
external SI
library eats memory?
That's why it is internal
on newer
versions.
Mike, WA6ISP
On 11/5/2017 1:00 PM, Henning Weddig via Groups.Io wrote:
yes, now it compiles:
"Build-Optionen wurden ver?¡èndert, alles wird neu kompiliert
Der Sketch verwendet 15464 Bytes (50%) des
Programmspeicherplatzes. Das
Maximum sind 30720 Bytes.
Globale Variablen verwenden 838 Bytes (40%) des dynamischen
Speichers,
1210 Bytes f??r lokale Variablen verbleiben. Das Maximum
sind 2048
Bytes."
but I am wondering why this sketch uses abouzt 50% of the
available
programm memory space !
Henning
Am 05.11.2017 um 21:54 schrieb Michael Hagen:
OK, comment out LCD.H
and
// LCD Backlight ON
//lcd.setBacklightPin(BACKLIGHT_PIN,POSITIVE);
//lcd.setBacklight(HIGH);
Now it compiles here?
Look like those
functions are in some
other library other than the standard Liquid Crystal
library?
?
WA6ISP, Mike
--
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID?
"MotDog@..."
Mike@...
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Henning,
I added these libs and it compiles as is..
I could not send this to the group so here are the dropbox links
Raj
At 07-11-2017, you wrote:
toggle quoted message
Show quoted text
Michael,
after commenting out the two header files You stated below, I had to
comment out a lot more lines, then it compiled, only 5 k of code, see the
attached sketch. But i am not sure if this code will give a working
result.
I got Your pcb, but have not populated it due to non existing files i.e.
schematics, layout. I remember You sent it to me but momentarily I can
not find these files...
Henning
Am 05.11.2017 um 22:06 schrieb Michael Hagen:
Probably these?
#include "si5351.h"
#include <Rotary.h>
Remember the complaint the external SI
library eats memory?
That's why it is internal on newer
versions.
Mike, WA6ISP
On 11/5/2017 1:00 PM, Henning Weddig via Groups.Io wrote:
yes, now it compiles:
"Build-Optionen wurden ver?¡èndert, alles wird neu kompiliert
Der Sketch verwendet 15464 Bytes (50%) des Programmspeicherplatzes. Das
Maximum sind 30720 Bytes.
Globale Variablen verwenden 838 Bytes (40%) des dynamischen Speichers,
1210 Bytes f??r lokale Variablen verbleiben. Das Maximum sind 2048
Bytes."
but I am wondering why this sketch uses abouzt 50% of the available
programm memory space !
Henning
Am 05.11.2017 um 21:54 schrieb Michael Hagen:
OK, comment out LCD.H
and
// LCD Backlight ON
//lcd.setBacklightPin(BACKLIGHT_PIN,POSITIVE);
//lcd.setBacklight(HIGH);
Now it compiles here?
Look like those functions are in some
other library other than the standard Liquid Crystal library?
?
WA6ISP, Mike
--
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID?
"MotDog@..."
Mike@...
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Re: BITX40 build for SOTA/POTA operation
Nice case peatmoss. I like that you brought out a usb connector so you don't have to disassemble every week when Allard has a great new software upgrade. It looks like another pot without a knob was also added. What is it for?
I usually just carry 2 lengths of 1/4 wave wire on a winder. I throw one end up in a tree and lay the other on the ground. The downside of a half wave is that you need a longer wire which is tougher to get up in the air. The plus is that if you can use a half wave wire you can get the high current point up in the air.
??? Bob
?????? KD8CGH
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Arthur Bryant
Raj vu2zap
Bob Benedict, KD8CGH