Re: uBitx V4 linearity mod in final audio amplifier
#ubitx
On Monday, June 18, 2018, 7:27:20 AM PDT, ajparent1/KB1GMX <kb1gmx@...> wrote:
?However the one I use when not using? LM386 is the circuit on page 1.12 figure 1.17 in EMRFD. The EMRFD design has a number of features that make it desirable, actively set bias and feedback being significant. It always works when I build it and? its clean sounding.?? Allison I second this ....Not hi-fi, Just works well
Jim
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I have a new (upopened) uBitx which I ordered as I started working on my first unit. The is a version just before V4 and has the socketed audio power amplifier.
Eyes were bigger than stomach and it's clear I won't get to this second unit for several months.
Therefore, I am happy to ship this unit to anyone who can use it for $95 with free USPS shipping in the US, paid to my PayPal account.
I'll pick up a new one when/if I start a second system.
73,
Paul K2AYZ
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Re: Help with AGC kit wiring
OK, a picture it is. I would be more inclined to move the AGC board to the right, near K3     . This shows the AGC and uBITX boards parallel (second option in #7 of my note below).
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Re: No S-Meter nor callsign showing in KD8CEC
#ubitx
In the memory manager under User Interface I do not have anything checked before the S-meter. Try unchecking the Always Display Call and Scroll Display.
de ku4pt
On Mon, Jun 18, 2018 at 3:54 PM, Sascha Bohnet via Groups.Io <saschabohnet@...> wrote: Yes, the firmware I have in use is UBITX_CEC_V1.080_16P.hex - the standard display.
I did activate the S-Meter in the Memory Manager (I am using uBITX_MM_V1.081 here).
I have attached my configuration file. Maybe there is something what I am just overlooking.
The values which have added for S-Meter steps are fictional - i wanted to do the calibration later with my lab equipment.
But I can read out the ADC values of A7 and I get always changing values between 30 and 190 if i tune to an AM Broadcasting station.
As these values are withink the steps I defined, i think something should be shown. Or could it be that the values are changing too fast?
I have also attached a picture of the wiring of my ND6T AGC_KIT Wiring. I think I connected it properly but maybe I am wrong.
However I think the mistake is somewhere within the software. Instead of the S-Meter in the right corner ?
I just get shown "ST" which i think is short for "XXX Hz Tuning STEP", right?
And somewhere my Callsign should also scroll within the screen with these configuration, or am I wrong?
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Re: KD8CEC - Nextion Display - IAN questions
any word on when 1.09 is going to be ready to download?? ?
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Re: The BITeensio board is here.
#ubitx
Jack, sorry I'm slow getting back to you on the video microscope. My bottom line opinion is that you save the $60?and put it towards something better.
I bought one of these from Banggood back when it only came with a suction cup style mount. It was so unstable for taking a photo that I disassembled the unit and added an external pushbutton on a cable. Later they introduced the aluminum stand and I bought one. With that it at least made it usable.?
I found that there didn't seem to be any difference in the resolution settings from 5mp down to 1.3mp photos and if I tried to take photos in the 5mp setting that about half the time the unit would freeze and I had to hit the reset button. So I just left it in 1.3mp. So strike one against it, better to take photos with my cellphone! Next the display screen, it's contrasty, poor color saturation and low resolution. So you might use this for some inspection work but I sure wouldn't use it for actual solder work. Strike two, better to use a jewelers magnifying band that I've used for years. Last but not least is the integrated light, which is not bright enough to adequately illuminate the subject without being extremely close. A couple of the photos on the shared album where taken while holding a strong flashlight to the side. There's one taken with only the integrated light and another with the flashlight. I'd thought about adding side lights on both sides of the unit to get adequate balanced lighting.??
This link will take you to a shared album with some photos that hopefully give you a visual idea of what I'm talking about.
Mine has firmware version 1.3 and that appears to be latest version. So nothing has been done to fix any of the flackyness. If someone else has purchased one recently and check their firmware version it would be interesting to verify.
Roy WA0YMH
On Sun, Jun 17, 2018, 8:31 AM Jack Purdum via Groups.Io <jjpurdum= [email protected]> wrote:
Has anyone tried this type of scope:
(eBay 352344602558)? For $60, I'd be very interested if it works.
Jack, W8TEE
On Sunday, June 17, 2018, 1:16:28 AM EDT, Kevin Luxford < kbgluxford@...> wrote:
To my dear XYL's chagrin, I have just purchased a stereo AmScope SE400-X
microscope with fixed 5x or 10x magnifications (depending upon the
eyepice selected).? This has a 9 inch distance to the work object and a
wide field of view, so very little chance of burning one's nose with the
soldering iron. But USD200! + freight down here to Oz.? However it
provides a stereo view of the pcb with great clarity.? I understand that
freight to CONUS is free. Usual disclaimers.
73 all,
Kevin VK3DAP? / ZL2DAP
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Audio feedback during transmit?
#ubitx
I'm having audio feedback during transmit through my external speaker.!? I have the issue even with a dummy load.? I hear my voice (distorted) on the receive side when transmitting on any band. Anyone else have this issue?
Thanks,,
Jim W0CHL
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Re: KD8CEC - Nextion Display - IAN questions
Not the cheapest but it got here in three days!!
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Mark,
I went through the same agony in making a decision, and have been VERY happy with mine. The Ammeter is wonderfully accurate too. The harbor freight meters are?junk sorry guys. I don't trust them.?
I wrote about my search and why I chose the one I did on my blog. $20 was all that I needed to spend:
--
Ryan Flowers - W7RLF
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Re: KD8CEC - Nextion Display - IAN questions
The battery is for the Real Time Clock - not required at this stage.
Yes E version of TFT file is for the enhanced version.? The functionality initially will be identical for both standard and enhanced versions of the Nextion.
Mike ZL1AXG uBITx.net
On Tue, 19 Jun 2018 at 8:06 AM, Gary Shriver < gshriver@...> wrote: Ian (and the group)? In great anticipation of running the Nextion display on my uBitx, I purchased a 2.8¡±display on ebay and it arrived today.? I ordered the ¡°Enhanced¡± version and I found a lithium battery socket on the board.? Do I have to run a lithium battery for this board to work?? I figured it would be powered by the uBitx but was wondering if I had to have the battery installed for it to remember the settings I upload to it.? If the battery is required, does anyone know which battery it calls for?? Nothing on the board and no instructions came with the board so I¡¯m in the dark on this one.?
Also Ian,? would I use the GUI firmware ¡°ubtix_28_E.tft¡± file?? I was thinking that the ¡°E¡± was for the enhanced version of the Nextion board.?
Also, do you have any idea when the 1.09 firmware version is going to be available for download?? Can you tell I am really excited about this mod??!!!?
Thanks for all you do Ian, U-Da-Man!? I haven¡¯t had this much fun in years.?
73-Gary
KC6SWL
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Re: Help with AGC kit wiring
Just noticed I forgot a picture.
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Re: Transmit indicator light.
Roy? WA0YMH
Yes.? It works fine with just a couple inches of twisted hookup wire between toroid
and LED.? Adjust the number of turns for slightly less than full brightness at full
power.? FT37-43 cores work well, but for 40M you can use one of the clip-on ferrites
or the green core liberated from a dead CFL light bulb.?
This is not a particularly new or original idea.? It has been floating around the airwaves
for many years.?
Arv? K7HKL
_._
Arv, so you have used this method in a QRP transceiver? Did you run the wire to the LED as a simple twisted pair or a piece of mini coax?
Roy WA0YMH
Roy WA0YMH
Probably could use a diode rectifier and filter cap at the toroid location and run
DC to the front panel LED.? I have never tried that because radiated RF inside
the chassis has never been a problem.
Using a rectifier and filter cap could also let you measure RF current on an ADC
input of the Arduino.? Interesting thought that if you measure RF current and RF
voltage at the antenna jack it might be possible to calculate antenna impedance.
Arv? K7HKL
_._
The following is a question not a statement.
Typically the ant lead is at the back of a radio case and the LED indicator would be on the front panel. Wouldn't running the wires feeding the LED that distance cause a potential of rf radiation into the radio?
Roy WA0YMH
On Mon, Jun 18, 2018 at 8:07 AM Praba Karan < vu3dxr@...> wrote: Circuit diagram to enable this idea?..
On Sat, Apr 21, 2018, 3:51 AM Don, ND6T via Groups.Io <nd6t_6= [email protected]> wrote: In my opinion, the very best LED transmit indicator was the one that Derry Spittle (VE7QK [SK]) used in his Epiphyte QRP SSB series. That was just a 470 ohm quarter watt resistor through a small toroid and attached to a panel-mounted LED at each leg. The lead to the antenna passed through next to that resistor. That was it! When RF went to the antenna, it lit. You could easily tell if you were speaking loudly enough into the microphone, etc. Fast response, little panel space, and EASY. 73, Don
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Re: Help with AGC kit wiring
I have made some photos of how I did it. You need to keep rather to the left (near K1) as on the right there are some lines on the bottom of the PCB.
Also i had to solder the socket on the AGC PCB with an angle - since this toroid above R89 would have been to close to the AGC. So its a bit tilted in my construction.
Maybe this helps a bit
Sascha, DL5SMB
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Re: KD8CEC - Nextion Display - IAN questions
On Mon, Jun 18, 2018 at 01:05 pm, Gary Shriver wrote:
I purchased a 2.8¡±display on ebay and it arrived today.?
Hi, Gary. Can you share the link for the item you purchased? Thanks!
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KD8CEC - Nextion Display - IAN questions
Ian (and the group)? In great anticipation of running the Nextion display on my uBitx, I purchased a 2.8¡±display on ebay and it arrived today.? I ordered the ¡°Enhanced¡± version and I found a lithium battery socket on the board.? Do I have to run a lithium battery for this board to work?? I figured it would be powered by the uBitx but was wondering if I had to have the battery installed for it to remember the settings I upload to it.? If the battery is required, does anyone know which battery it calls for?? Nothing on the board and no instructions came with the board so I¡¯m in the dark on this one.?
Also Ian,? would I use the GUI firmware ¡°ubtix_28_E.tft¡± file?? I was thinking that the ¡°E¡± was for the enhanced version of the Nextion board.?
Also, do you have any idea when the 1.09 firmware version is going to be available for download?? Can you tell I am really excited about this mod??!!!?
Thanks for all you do Ian, U-Da-Man!? I haven¡¯t had this much fun in years.?
73-Gary
KC6SWL
|
Re: Transmit indicator light.
Jerry
Beauty of the little toroid and LED trick is its simplicity and ease of use.
Of course if we were to build something like this inside a BITX it should probably be
a real SWR bridge with phase compensation and so on.
Arv
_._
On Mon, Jun 18, 2018 at 1:22 PM Jerry Gaffke via Groups.Io <jgaffke= [email protected]> wrote: Phase is important, if you are measuring current and voltage at the antenna port
you will also want to measure the phase angle between the two.
A Tandem Match more or less measures voltage and current into the antenna.
This one is $12:? ? ??
T1 is a current transformer, T2 is a voltage transformer,
Actually, a Tandem Match adds the voltage and current readings in phase and out of phase
from which an SWR relative to 50 ohms can be calculated.
From those readings, can also calculate forward and reverse power in Watts..
Primary trick on a Tandem Match is that the voltage and current are scaled such that if driving a 50 ohm load,
the sum of the two when out of phase is zero.??
The Bruene and Monimatch designs do about the same as a Tandem Match.??
This 1959 Bruene article is a classic, recommended:??
Here's a full analysis of the Tandem Match:??
Another tutorial on SWR meters:??
There are others.
An advantage of the Tandem Match is that the transformer ratios pretty much calibrate it
for both absolute power into 50 ohms, and SWR.?
Unlike the resistive bridges typical of qrp swr meters, a Tandem Match (or Bruene or Monimatch and friends)
can remain inline to monitor correct antenna functioning while operating the transmitter.
If you really want to explore antenna impedances to 440mhz and maybe do two port measurements,
check out?Kee's AQRP Vector Impedance Analyzer near the bottom of this webpage:
? ??
That one really does measure voltage and current into the antenna, along with the phase angle.
And can do much much more.
Jerry, KE7ER
?
On Mon, Jun 18, 2018 at 11:10 am, Arv Evans wrote:
Probably could use a diode rectifier and filter cap at the toroid location and run
DC to the front panel LED.? I have never tried that because radiated RF inside
the chassis has never been a problem.
Using a rectifier and filter cap could also let you measure RF current on an ADC
input of the Arduino.? Interesting thought that if you measure RF current and RF
voltage at the antenna jack it might be possible to calculate antenna impedance.?
|
Re: No S-Meter nor callsign showing in KD8CEC
#ubitx
Yes, the firmware I have in use is UBITX_CEC_V1.080_16P.hex - the standard display.
I did activate the S-Meter in the Memory Manager (I am using uBITX_MM_V1.081 here).
I have attached my configuration file. Maybe there is something what I am just overlooking.
The values which have added for S-Meter steps are fictional - i wanted to do the calibration later with my lab equipment.
But I can read out the ADC values of A7 and I get always changing values between 30 and 190 if i tune to an AM Broadcasting station.
As these values are withink the steps I defined, i think something should be shown. Or could it be that the values are changing too fast?
I have also attached a picture of the wiring of my ND6T AGC_KIT Wiring. I think I connected it properly but maybe I am wrong.
However I think the mistake is somewhere within the software. Instead of the S-Meter in the right corner ?
I just get shown "ST" which i think is short for "XXX Hz Tuning STEP", right?
And somewhere my Callsign should also scroll within the screen with these configuration, or am I wrong?
|
Re: Transmit indicator light.
Arv, so you have used this method in a QRP transceiver? Did you run the wire to the LED as a simple twisted pair or a piece of mini coax?
Roy WA0YMH
Roy WA0YMH
Probably could use a diode rectifier and filter cap at the toroid location and run
DC to the front panel LED.? I have never tried that because radiated RF inside
the chassis has never been a problem.
Using a rectifier and filter cap could also let you measure RF current on an ADC
input of the Arduino.? Interesting thought that if you measure RF current and RF
voltage at the antenna jack it might be possible to calculate antenna impedance.
Arv? K7HKL
_._
The following is a question not a statement.
Typically the ant lead is at the back of a radio case and the LED indicator would be on the front panel. Wouldn't running the wires feeding the LED that distance cause a potential of rf radiation into the radio?
Roy WA0YMH
On Mon, Jun 18, 2018 at 8:07 AM Praba Karan < vu3dxr@...> wrote: Circuit diagram to enable this idea?..
On Sat, Apr 21, 2018, 3:51 AM Don, ND6T via Groups.Io <nd6t_6= [email protected]> wrote: In my opinion, the very best LED transmit indicator was the one that Derry Spittle (VE7QK [SK]) used in his Epiphyte QRP SSB series. That was just a 470 ohm quarter watt resistor through a small toroid and attached to a panel-mounted LED at each leg. The lead to the antenna passed through next to that resistor. That was it! When RF went to the antenna, it lit. You could easily tell if you were speaking loudly enough into the microphone, etc. Fast response, little panel space, and EASY. 73, Don
|
Re: BITX QSO Afternoon/Evening, Sunday, June 17, 3PM & 7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere.
QRM was pretty bad here in Orlando. I never did have any replies or hear anyone. So worked on getting digital working. Did hear a WSPR above my noise level on 30 so all wasn't dead
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Re: Transmit indicator light.
very good explanations Jerry. an another realisation
Gilles F1BFU / FR
Phase is important, if you are measuring current and voltage at the antenna port
you will also want to measure the phase angle between the two.
A Tandem Match more or less measures voltage and current into the antenna.
This one is $12:? ? ??
T1 is a current transformer, T2 is a voltage transformer,
Actually, a Tandem Match adds the voltage and current readings in phase and out of phase
from which an SWR relative to 50 ohms can be calculated.
From those readings, can also calculate forward and reverse power in Watts..
Primary trick on a Tandem Match is that the voltage and current are scaled such that if driving a 50 ohm load,
the sum of the two when out of phase is zero.??
The Bruene and Monimatch designs do about the same as a Tandem Match.??
This 1959 Bruene article is a classic, recommended:??
Here's a full analysis of the Tandem Match:??
Another tutorial on SWR meters:??
There are others.
An advantage of the Tandem Match is that the transformer ratios pretty much calibrate it
for both absolute power into 50 ohms, and SWR.?
Unlike the resistive bridges typical of qrp swr meters, a Tandem Match (or Bruene or Monimatch and friends)
can remain inline to monitor correct antenna functioning while operating the transmitter.
If you really want to explore antenna impedances to 440mhz and maybe do two port measurements,
check out?Kee's AQRP Vector Impedance Analyzer near the bottom of this webpage:
? ??
That one really does measure voltage and current into the antenna, along with the phase angle.
And can do much much more.
Jerry, KE7ER
?
On Mon, Jun 18, 2018 at 11:10 am, Arv Evans wrote:
Probably could use a diode rectifier and filter cap at the toroid location and run
DC to the front panel LED.? I have never tried that because radiated RF inside
the chassis has never been a problem.
Using a rectifier and filter cap could also let you measure RF current on an ADC
input of the Arduino.? Interesting thought that if you measure RF current and RF
voltage at the antenna jack it might be possible to calculate antenna impedance.?
|
Paul Galburt - K2AYZ
Arvo W0VRA
