Replacing the PA section on Bitx 40
Hello,
My shipment of replacement RF Mosfets have arrived and I want to replace the on board PASection with one based on the RD16HHF1. It will be a separate small PCB based on the reference design shown in the data sheet. I need help from the professionals here as to where to attach the new PA board.
I know it would be somewhere after the 2N2219A driver, and I want to remove all bypassed SMTs and or other parts from the Bitx board in that area. If you have a pretty good idea could you please let me know, and possibly a drawing if you could. This should keep me busy and off the forum for a while.
Thanks,
James Lawrie
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Re: uBITX woes, feeling disheartened.
#ubitx
Hi Chris -?
Replying to your suggestion to check DC path.? Unfortunately there is a path to DC no matter if it's TX or RX.? The RX path goes through K1.??
I have verified 12v across D7 (K1) when PPT is on.? ?Still stumbling around ...?
--
Dave Beal
AE6RQ
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Jack, ? Nope, it has its own processor that takes care of the refresh. With the downloadable software you define touch areas, display areas etc. This is downloaded to the onboard processor via either serial of much faster via an SD card. The data defining characteristics and page numbers once down loaded are populated via the serial bus. The STM32 discovery boards availabl for less than $20 contain the BitX program (you can use the same IDE as used for the Arduino once the libraries are downloaded). It took me less than 20 minutes to define 4 pages to control all the functions. Thanks to your tutelage I was able to simply modify the portions of the BitX program I used with a 20X4 display. With the touch screen I can enter the frequency directly and pass it to the STM32 processor. Works well with the Arduino Mega as well using TX2/RX2. The software from the screen vendor allows you to prepare the files, simulate the screen and then when you happy send it to the SD card for installation. Once you get familiar with the simulator you can create an application in less than an hour. Once data has been passed to the screen you can disconnect the Arduiano/STM32 and the display continues on displaying the last data received in the fields defined by the SD card info. Screen sizes up to 7 inch are available albeit a bit pricey. I am using the 3.5 inch. ? v/r Fred W4JLE ?
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From: [email protected] [mailto:[email protected]] On Behalf Of Jack Purdum via Groups.Io
Sent: Wednesday, January 31, 2018 21:22
To: [email protected]
Subject: Re: [BITX20] Nextion Display? How's the refresh rate? Any flicker?
From: Dr Fred Hambrecht <w4jle@...>
To: [email protected]
Sent: Wednesday, January 31, 2018 7:43 PM
Subject: Re: [BITX20] Nextion Display ? I am using the serial connection. No drivers needed. Are you running the Nextion from the STM32? No driver issues?
From: Dr Fred Hambrecht <w4jle@...>
To: [email protected]
Sent: Wednesday, January 31, 2018 2:13 PM
Subject: [BITX20] Nextion Display I may be late to the party, but I have just discovered the NEXTION?display. I am using it on my BitX. What makes it really neat is the software that can be downloaded from the manufacturer's site. It takes all the pain out of graphics programming. I have also replaced the UNO with an STM32 as in addition to the normal stuff I have added a GPS module to display time/location/grid square data as well as using the 1PPS to do a continuous correction to the SI oscillator. The higher resolution allows calculating the SWR etc with much finer gradations.? I will be adding a filter board from a CODAN that will allow all band operation.(bought for $12.00 on EBay). Amazing what is available to the?homebrewer today! ?
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Which display width did you procure for the NEXTION?
Pat, VU3PAT
On Thursday, February 1, 2018 7:55 AM, Jack Purdum via Groups.Io <jjpurdum@...> wrote:
Did not know that, as I've never had one. Thanks!
Jack, W8TEE
From: Michael Monteith via Groups.Io <michael_r_monteith@...> To: [email protected] Sent: Wednesday, January 31, 2018 6:24 PM Subject: Re: [BITX20] Nextion Display Jack, ?The Nextion display only uses a serial port.? Software is written on the processor on the display to change the display contents based on data sent back and forth on the serial port.??? This allows in this case the external processor to deal with data a processing and letting the display itself to handle graphics content.? 73, Michael KM4OLT On Wed, Jan 31, 2018 at 11:48 am, Jack Purdum wrote:
Fred:
?
Are you running the Nextion from the STM32? No driver issues?
?
Jack, W8TEE
?
?
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UBITX: Guide page for wiring up a Paddle and Straight Key on ubitx.net
I had a bit of time up my sleeve today, so I have drafted one of the guide pages on the website:
???
I need better photos of the paddle and straight key jacks.? Can somebody send me some better photos (jpg)?
I am happy to take any other suggestions to improve this page as well!
73 Mike
--
Mike Woods
mhwoods@...
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Re: uBITX AM BCI Filter
#ubitx
Hi John, Ill get it installed tonight...
However, I do have one already installed using T37-6 and tantalum caps that seems to be working fine. It is on the ANT though, So I am hoping puting this new one on the RX path help with TX power (Marginal I imagine...)
Wanna try SKED on the weekend, say Sunday 7pm on 7177, as per other uBITX skeds?
Cheers. Nick
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Re: [uBITX] Key line resistor: OK to mount on Raduino board?
I soldered it at the board.? No issues.
Marco - KG5PRT?
On Jan 31, 2018 8:20 PM, "Jerry Gaffke via Groups.Io" <jgaffke= [email protected]> wrote: Should be fine, only concern might be if your soldering iron was faulty and the tip was not at ground potential.?
In fact, installing the 4.7k at the Raduino may be slighty preferred,
as there's less chance of the rig unexpectedly transmitting due to an open cable or connector.?
On Wed, Jan 31, 2018 at 06:11 pm, K5DH wrote:
There is a 4700 Ohm pullup resistor that must be installed between +5 V and the key line.? The wiring instructions show it being installed at the key jack.? Is it OK to install it on the Raduino board, on the solder side of the Digital connector?? Or is soldering to that board too risky??
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Did not know that, as I've never had one. Thanks!
Jack, W8TEE
From: Michael Monteith via Groups.Io <michael_r_monteith@...>
To: [email protected]
Sent: Wednesday, January 31, 2018 6:24 PM
Subject: Re: [BITX20] Nextion Display
Jack, ?The Nextion display only uses a serial port.? Software is written on the processor on the display to change the display contents based on data sent back and forth on the serial port.??? This allows in this case the external processor to deal with data a processing and letting the display itself to handle graphics content.? 73, Michael KM4OLT On Wed, Jan 31, 2018 at 11:48 am, Jack Purdum wrote:
Fred:
?
Are you running the Nextion from the STM32? No driver issues?
?
Jack, W8TEE
?
?
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How's the refresh rate? Any flicker?
Jack, W8TEE
From: Dr Fred Hambrecht <w4jle@...>
To: [email protected]
Sent: Wednesday, January 31, 2018 7:43 PM
Subject: Re: [BITX20] Nextion Display
Jack, I am using the serial connection. No drivers needed. ? v/r Fred W4JLE ? ? ? Are you running the Nextion from the STM32? No driver issues?
From: Dr Fred Hambrecht <w4jle@...>
To: [email protected]
Sent: Wednesday, January 31, 2018 2:13 PM
Subject: [BITX20] Nextion Display ? I may be late to the party, but I have just discovered the NEXTION?display. I am using it on my BitX. What makes it really neat is the software that can be downloaded from the manufacturer's site. It takes all the pain out of graphics programming. I have also replaced the UNO with an STM32 as in addition to the normal stuff I have added a GPS module to display time/location/grid square data as well as using the 1PPS to do a continuous correction to the SI oscillator. The higher resolution allows calculating the SWR etc with much finer gradations.? I will be adding a filter board from a CODAN that will allow all band operation.(bought for $12.00 on EBay). Amazing what is available to the?homebrewer today! ?
|
Re: [uBITX] Key line resistor: OK to mount on Raduino board?
Should be fine, only concern might be if your soldering iron was faulty and the tip was not at ground potential.?
In fact, installing the 4.7k at the Raduino may be slighty preferred,
as there's less chance of the rig unexpectedly transmitting due to an open cable or connector.?
toggle quoted message
Show quoted text
On Wed, Jan 31, 2018 at 06:11 pm, K5DH wrote:
There is a 4700 Ohm pullup resistor that must be installed between +5 V and the key line.? The wiring instructions show it being installed at the key jack.? Is it OK to install it on the Raduino board, on the solder side of the Digital connector?? Or is soldering to that board too risky??
|
[uBITX] Key line resistor: OK to mount on Raduino board?
There is a 4700 Ohm pullup resistor that must be installed between +5 V and the key line.? The wiring instructions show it being installed at the key jack.? Is it OK to install it on the Raduino board, on the solder side of the Digital connector?? Or is soldering to that board too risky??
73/72,
Dean K5DH
uBITX msn 279
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Re: uBITX AM BCI Filter
#ubitx
Hello Nick,
This is looking very good.
I will try a quick version tomorrow with T68-6 toroids (the smallest size I have handy) in the antenna circuit just to see how much attenuation I get. I am using the same circuit as yours and re-calculated the turns for the T68-6.
If that works I will order some small T30-6 toroids and do the same a you.
Please let me know the results when you wire yours up. I will keep you informed of my results.
All the best,
73, John (VK2ETA)
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I believe you will find that the front and rear panels for these cases are isolated electrically from the rest of the cabinet. They nestle into the plastic rim around the front and the back.?
If you want an RF proof enclosure you will have to run a ground wire from the panels to the rest of the case.?
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Re: Found another case for the Ubitx
I have one on back order. I have the smaller one and I just can’t get the ubitx in it. However it is a nice case so I backordered the bigger one
Bob
W5rkm
On Jan 31, 2018, 5:34 PM -0600, wishbone_aaa <dlmock@...>, wrote:
Looks like this would be a good candidate.
https://www.circuitspecialists.com/metal-instrument-enclosure-la-6.html
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Re: Software support Request for Full QSK BITX40
If the IRF510 gate is driven hard with a square wave, it switches fine at 7mhz and beyond, showing a nice square wave
for drain voltage (0-24v) and drain current with troughs all the way to zero.? That's with a 50 ohm antenna load, supply at 12v.
If the antenna port impedance is 10000 ohms at 7mhz, those drain and antenna port voltages roughly double,
and drain currents are kept fairly small.? ? I assume the lack of major voltage spikes is because
there remains some drain current in the troughs?due perhaps to miller effect capacitance
If the antenna port impedance is 10000 ohms at 7khz, the simulation shows
the kilovolt spikes I'd expect from a flyback transformer.
??
Quite curious.
But I think I'm ready to start playing with the uBitx, as the push-pull final there should be more predictable.
Jerry
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On Wed, Jan 31, 2018 at 03:32 pm, Jerry Gaffke wrote:
So T7 does indeed behave like a flyback transformer at slow speeds, but at 7mhz the IRF510
stays on to where that coil current always has somewhere to go, T7 behaves more like a forward transformer.
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Jack, I am using the serial connection. No drivers needed. ? v/r Fred W4JLE ? ?
toggle quoted message
Show quoted text
From: [email protected] [mailto:[email protected]] On Behalf Of Jack Purdum via Groups.Io
Sent: Wednesday, January 31, 2018 14:48
To: [email protected]
Subject: Re: [BITX20] Nextion Display? Are you running the Nextion from the STM32? No driver issues?
From: Dr Fred Hambrecht <w4jle@...>
To: [email protected]
Sent: Wednesday, January 31, 2018 2:13 PM
Subject: [BITX20] Nextion Display ? I may be late to the party, but I have just discovered the NEXTION?display. I am using it on my BitX. What makes it really neat is the software that can be downloaded from the manufacturer's site. It takes all the pain out of graphics programming. I have also replaced the UNO with an STM32 as in addition to the normal stuff I have added a GPS module to display time/location/grid square data as well as using the 1PPS to do a continuous correction to the SI oscillator. The higher resolution allows calculating the SWR etc with much finer gradations.? I will be adding a filter board from a CODAN that will allow all band operation.(bought for $12.00 on EBay). Amazing what is available to the?homebrewer today! ?
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Re: Fixing a blown Raduino board
Bernie:
Usually a "ticking" noise is caused by communication
between the chip and the LCD. It may not be that, however.
Anyway it is a kind of "normal" RFI from a uPC. Usually it can be
eliminated with proper wire dressing or shielding. Most uBITX'ers
have used shielding on extension cables for the LCD because
that is when they hear it.
john
AD5YE
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Re: Found another case for the Ubitx
Got one on backorder for my third uBITX. ?uBITX should ship pretty soon so I hope the case backorder doesn't take too long too. ?I've used the smaller versionsions of this case on other projects and it's really nice to work with but the aluminum front and back panels are really soft aluminum so be careful drilling holes and cutting the LCD window.
Jim Sheldon, W0EB
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Re: UPLOAD FIRMWARE IN RADUINO
What are those lights on the nano anyway? And do I need them?
There are usually 4 leds on the nano. They are usually in a row and
labeled "RX TX PWR L".
The RX and TX lights are connected to the lines that connect both the USB
interface and the ATMega628P. They connect to TX0 and RX0. They are very
useful as their flashing shows that communication is taking place during an
upload. Likewise, if RX flashes once and then not again during an upload,
there is a communications problem. Usually they are red and green; some may
be orange. Messing with them will probably mess up RX0 and TX0. It is
best to leave them alone. They are always out (low) with no serial communication
to the chip. If they stay on, something is wrong...
PWR refers to a direct connection to the voltage regulated 5v line. It is NOT
connected to the input voltage, whatever that may be. It is an indication that
the board has power either from Vin or USB. That is all it does. It is usually
red though I have seen many orange lights. It is useful, but it could be eliminated,
I guess.
L is connected to D13. It is a good light and should not be disconnected. If the
ATMega has a bootloader (which it should in a nano) this will flash three times
when the reset button is pushed and released. That is not guaranteed because
earlier versions of the bootloader did not show themselves through D13. And
if the ubiquitous Blink program is loaded, it will falsh D13. That alone makes it
a good light to retain. It is your "diagnostic visual indicator".
Anyway, that is what those leds do.
Hope this helps.
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Found another case for the Ubitx
Looks like this would be a good candidate.
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James Lawrie
Patrick Pugh Sawian
Nick VK4PP
Bob McMillan
Jim Sheldon