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Dale Hardin, KS4NS
Elberta, AL

开云体育

Sorry to nit pick, however I do not know where to get 680nF inductors, only 680nH inductors.? I assuming that you do mean the 680 nanoHenry inductors that were suggested by?Raj, vu2zap in this thread:
/g/BITX20/topic/27154925#60568

That is unless I missed something about a part number.

Also, the relay and or off board filters do not address the spurs issues, only the harmonics issues.? The 2 spur fixes are either the shielded SMD inductors per Raj, or the Ashhar v5 fix with an LCL low pass filter before the last mixer in the transmitter chain.

It should be noted that there seems to be less harmonics when using SSB, but higher spurs on the upper bands.? For CW, Harmonics on the lower bands, and less on upper bands with little reported spurs on any band.?

This goes along with what I have been able to measure, though I do not trust the spurs testing that I did due to a poor RBW on the spectrum analyzers that I had at my disposal at the time.

73
Evan
AC9TU

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Dale Hardin, KS4NS
Elberta, AL

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Dale Hardin, KS4NS
Elberta, AL

Easiest soln? is to use a two chan level converter (~50 cents).?
You can also make a 3.3 v device the master, with pullups to 3.3 v source.? Arduino will read 3.3 v as high. ?

I have not yet done the mod, however KD8CEC at Hamskey.com has used the I2C line to link in second displays and Nano's for increased functionality.? To me that would imply that you can use the link to the Si5251.

FWIW
73
Evan
AC9TU

Hello, I have one of the 20x4 LCD displays on my uBITX, with the I2C backup to free up pins.? I removed the two pull-up resistors from the (5V) backup, so that I could use it in conjunction with the SI5351.??

Question... so I can't recall which pull-up is now getting used to pull the I2C lines up to 3.3V, but I'm wondering, can I add another I2C device to this bus, without adding any other conversions???

Specifically, I would like to use I2C to communicate between the Raduino and a Teensy 3.2 that I'm using for DSP audio filtering.? I was going to use serial, but I decided it was too much of a pain to try to interrupt the CAT stream, so I figured I'd try I2C instead.? But I want to make sure I can actually add the Teensy to the mix.

Thanks!
-Rob

Anyone have surplus 680nF inductors for V3 fix of spurious signals?? If so, contact me privately to discuss details.
Thanks, Dale
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Dale Hardin, KS4NS
Elberta, AL

Yes, those encoders are pricey.? I got mine for like $4 each from a surplus electronics shop in San Diego.? Though, having used them now, I'd still be tempted to use them even if I had to buy one new.? The issue most people have with using high ppr encoders with the uBitx is the processor is pretty slow and the encoder routines in the base Raduino code are not interrupt driven.? Also using digitalReadFast to read the encoders helps.? If you get much beyond a single 400/600 ppr encoder and you will likely need a faster processor to do it.? I'm using the BITeensio board with a Teensy 3.6 processor.? I've tested that board with two 1024 ppr optical? encoders with no problems.? Those encoders would be of little use to the uBitx thought, without some division ;-)

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John - N0CTL - Fulltime RV in a 40' motorhome

I went back and checked the QRP-Labs dummy load.? The connection is a filtered power indication.? This may not work for frequency counters, as the filter will lower the signal.? The small wire near the dummy is probably the best approach if you do not have a true attenuator.

Apologize for the miss information.
73
Evan
AC9TU?

Please be aware that the new v5 boards need to have the CEC version 1.2 or higher.? The IF frequency changed between the v4 and v5 boards.? IF you are going to go back to an older version of CEC for use on the v5 board you will need to go into the source and change the IF frequencies, recompile and then download.

Also be aware that the stock firmware requires a dummy load and separate receiver or frequency counter to calibrate.? The CEC software does not need the dummy load to calibrate.

The HF Signals' Tuneup web page instructions for step 2 are WRONG (Ashhar, this REALLY needs to be fixed!).? The stock firmware that I received on my v5 board put the uBITX into TRANSMIT mode at 10mhz.? Maybe this has changed with newer boards.

Since in my country (USA) 10MHz is not a valid ham frequency, a dummy load must be used.? I am pretty sure that this was done to facilitate the production testing/calibration process, however it does cause a problem if you are trying to calibrate and do not know that it will go into transmit mode at 10mhz.? It can also cause damage to the uBITX if left in this mode too long without a proper load. (note: QRP-Labs makes a nice 20 watt kit:?

For the stock firmware, dummy load and receiver/frequency counter setup, it is fairly easy to set the receiver to 10mhz (I assume that you calibrated the receiver/freq counter before this) and adjust the calibration until you get a zero beat on the receiver or 10 MHz on the counter.? Using a frequency counter, it is just a matter of connecting? to the counter through an attenuator to reduce the signal (the QRP-Labs dummy has a tap on it).? Most counters will work with a short wire held near the dummy load, no physical connection needed.? If you have an oscilloscope with a frequency counter built in, you could use it.? Most oscilloscopes are not that accurate, so I do not recommend this approach, unless being used as a relative reference.?

Once the master clock has been calibrated, I have found that the BFO is best adjusted with a free audio spectrum analyzer software.? Connect a mic to the PC, find a frequency with only static, hold the mic close to the speaker and adjust until the amplitude of the signal displayed is between 500 and 2500 Hz.

Free PC software:?

Above is my free advice, please use with caution as I could be wrong and will not assume any responsibility for it's use.
Good luck!
73
Evan
AC9TU

I also use this type of optical rotary encoder. It is much better and the feel is just perfect.
Between the encoder and the Radiuno I have a extra Arduino to adapt the pulses and divide them to not overrun the Radiuno.

I found a sketch by Jim Smith - G3ZQC and Glenn Percy - VK3PE to perform this task perfectly and only added some stuff for my project.

Try it !

Regards and 73's
PE1MHY
Guido

The one I've? I feel it smoother ans quieter and global better quality.?
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73's
Adrien F4IJA

What’s the benefit of using this encoder instead of the standard one??

All orders have been built and set for shipping. If by some random haze of madness I missed your order let me know. All orders will have a USPS tracking number linked to your paypal.

73

?More are on the way soon!
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David

?N8DAH