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Re: Best way to unsolder the Nano?
I use chipquick and wick On Wed, May 23, 2018, 6:45 AM Ralph Mowery <rmowery42@...> wrote:
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Re: Best way to unsolder the Nano?
I won't say it is the best, but what worked for me two times. Due to my fault while modifying the ubitx I had to replace the nano board. I used one of the hot air rework stations that can be bought off ebay for about $ 60 . It has a hand held wand that blows hot air out of about a 1/4 inch hole. You keep moving the wand from pin to pin? every second or less. That melts the solder and the whole board can be pulled out at once.? Then I used a solder sucker to clean out each hole that had solder left in it.? Just keep the heat down so as not to lift the traces off the board.? It does take some practice as how to do this.? Look on you tube for many examples of using it with the SMD. This is the one I used.? There are many sources for them on ebay.? Some from the US and some from China at many? different prices. You get a hot air gun and a soldering pencil that has some fine tips to replace the nano.? While I would not recommend this for heavy duty work, it holds up well enough for just a hobby.? If it quits, you are not out much money and can always get another. On Wed, May 23, 2018 at 9:20 AM, <Kd4epg@...> wrote: Need device on the best way to unsolder the nano board. |
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Re: Raduino issue
Jack Purdum
Probably obvious, but don't forget a button battery for the RTC and add code to set it when you're tethered to the PC, using its system clock to get the current date and time. There's plenty of code online for formatting the data to an LCD display. Jack, W8TEE
On Wednesday, May 23, 2018, 9:13:51 AM EDT, Sam Tedesco <stedesco619@...> wrote:
Ordered nano and clock board. Gonna start with nano then the 5351 ic. Anything else I should consider? Thx On Tue, May 22, 2018, 9:10 PM Sam Tedesco <stedesco619@...> wrote:
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Re: Best way to unsolder the Nano?
Jack Purdum
I think most will tell you to snip the legs of the Nano, remove it, and carefully unsolder each pin from the board, exercising care not to overheat the board and lift the pads. Jack, W8TEE
On Wednesday, May 23, 2018, 9:20:52 AM EDT, <Kd4epg@...> wrote:
Need device on the best way to unsolder the nano board. All help gratefully received. -- 72 and God bless KD4EPG |
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Re: Raduino issue
Ordered nano and clock board. Gonna start with nano then the 5351 ic. Anything else I should consider? Thx On Tue, May 22, 2018, 9:10 PM Sam Tedesco <stedesco619@...> wrote:
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Re: boosting the power on 28 MHz
#ubitx
David Robertson
Ashar, I did your modification which included shorting R83. I was careful to bag and tag all the removed components so I could remove the modification if needed.
I found the power out on 10 meters was 4 watts ( 1.2 watts before mod) and increased as we went down in frequency. On 80 meters it appears that I have about 18 watts out peak. Ran a couple of qsos and got good reports. Looks like this mod is a keeper! Thanks Ashar and thanks for such a good design. 73 Dave KD1NA |
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Re: Raduino CAD Files
Hi Guys!
I'm still trying to make the Pill work in the least intrusive way. It seems to me that the 5V from the Pill's USB connector only powers the 3.3V on-board? regulator, and everything else on the board runs from 3.3V. So my thinking is to put another 3.3V regulator on the Raduino board (I was going to do that anyway in order to have that voltage source) and feed that to the Pill's 3.3V pin via a PNP transistor that only turns on if there's no 5V present from the USB. This requires no mods to the Pill, but it does assume you can safely put 3.3V on the on-board regulator's output when there is no input voltage present.? Does this make sense and can anyone comment whether the regulator will tolerate an external voltage source on it's output when there is no input voltage? I think it will.? I can try it on the bench, but I don't think I'll have the opportunity for several weeks as I'm going on a trip. Joe |
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Re: Raduino CAD Files
The connector is simply a 0.1 inch spaced pin out. The rest are not really important. The gerbers are enclosed. - f On Wed, May 23, 2018 at 10:21 AM, <alitton@...> wrote: Joe, |
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Re: Raduino CAD Files
Joe,
Be it arduino or many other miniature processor boards I find there is very little attention paid to the power management on these little boards. No overvoltage protection, no reverse voltage protection, no fusing and as you found on the blue pill, the designers assume you will be powering the device through the USB which could be +5V, could be +3.3V or who knows what? Much is sacrificed for a miniature board without any overwhelming need for small size other than minimizing cost.? You will ultimately pay the price either on a well thought out board or in surrounding it with all those features on your own hardware.? The Teensy 3.x boards seem to have done much better job on this than most with fusing, reverse diode protection and USB power jumpering, at least 4 layer board among other things that I normally do on boards of this type. The NXP ARM processors are also usually available in distribution and about the same cost as ST. My only big problem with the teensy is its Arduino centric development environment, The 3.5 would be about the minimum for I/O requirements I'd want and at $24 for what they have on the board is pretty good. If I recall correctly the processor alone is around $13 in single quantity.? I don't see any fundamental problem with the onboard USB from a noise standpoint and if you want to ever do CAT control it is much better to have it closely coupled on the processor board rather than running it off-board.? As for EEPROM, the 128x8 I2C EEPROM we use that has a MAC address is $27 cents and in an SOT-23-6 package. A comparable 1kx8 I2C EEPROM is also around 30 cents or you can splurge and get a 32Kx8 I2C EEPROM for about 60 cents.? As for the SI5351 or other synthesizers I would have preferred placing it on the RF board rather than routing 3 rf clocks off the processor / user interface board through a header. I think that opens up many more problems than an I2C line run onto the RF Board. It is easy to manage the rise/fall times of the I2C and route them for minimal emission / crosstalk. I can't imagine the amount of LO radiation leakage being experienced in remoting the Radunio board from the uBITX board as a number of folks do.? For me it is usually more about the development environment and ease of code development and debugging. I used to do almost exclusively PIC processor design and spent many years waiting for an ARM development and debugging environment equal to the venerable MPLAB development environment. The STM environment with their acquisition of Atollic is getting close. ST-Link single wire debuggers are cheap. Development platforms like the Nucleo and Discovery series of boards are relatively cheap as well. One of the first STM boards I had experience with was the Discovery board used in Kees Vector Impedance Meter and was surprised at how inexpensive it was.? I like the additional flash memory, internal speed and peripheral mix on the ARM processors and the relatively low cost and availability in distribution of the STM (and NXP) processors.? As seen by the discussions here it is clear that the software requirements for "simple" radios like the uBITX are bumping up against the speed and memory limitations of 8 bit processors.? I hope you have a great month long vacation! Allen K5ABL |
Arvo W0VRA
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