Saturday, March 21, 2020

New Technology for 2020 ~ Lets Build a Phasing SSB Transceiver

LBAPT ~ Let's Build a Phasing Transceiver!

3/24/2020 ~ A bit of new hardware!


After a Skype session with ZL2CTM and also in an attempt to produce a quadrature output Si5351 --- I finally bumbled and stumbled through  many failures and now have something working (with a lot of help from around the world).


The idea of a quadrature output Si5351 has been around for some time, only I was not too successful in implementing the actual hardware -- until now. It gets harder as you get older! 

In my conversation with ZL2CTM he mentioned the idea of using a separate Arduino/Si5351 to generate the Quadrature outputs to free up the workload on the Teensy 4.0 which is running at 600 MHz and is fast. This then opens up the possibility of two displays. One could do an amazing spectrum waterfall piece and another would do just the frequency and other housekeeping tasks like Step Tuning Function, Sideband Select, etc.

One critical piece is the library that you use for the Si5351. Frankly this has me confused as I have four different versions of the Si5351 library and one caused you to have a 180 Degree shift an another a 45 Degree shift. I simply do not know why. But I guess the third time got me there.


This is all preliminary but having the separate Arduino /Si5351 Quadrature output is a piece needed for our Phasing Transceiver project. 

By the Way check out the LTC5599 IC from Analog Devices. It is a 30MHz to > 1Ghz SDR transmitter on a chip and can be had for about $11. One ham shared with me he has this working on 17M. 

Ahhh the new technology in 2020 is amazing!

If you are interested in hearing straight talk about the Covid-19 tune into one of the briefings by Governor Andrew Cuomo from New York. Listening to the emperor (with a small e) is a waste of time and riddled with misinformation (MOM).

I personally believe that blindly following the emperor (with a small e) puts you at a grave risk! You only need to observe the daily exponential growth in cases to see that opening the country by Easter is unthinkable.

Its like saying use a 47 Ohms resistor --it is ok just use a 1/4 watt. But the load requires a 100 watt. True same value wrong watt rating! Listen to Dr. Fauci and Governor Cumo. They know best!

Is the drive to open by Easter purely a personal desire -- surely the Trump properties are tanking right now? Some sobering food for thought. 

73's
Pete N6QW


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Fellow Hams --we are on our own! The lack of leadership at the top has put us all at risk. There is a huge difference in "playing a president" and being one. A real leader would have taken immediate and decisive action -- he took a golfing trip! 

It is really easy to spot the true "leaders" in the fight against CV-19: Cuomo, Newsome, Inslee.

Just observe --- the $2 Trillion Stimulus package will benefit the rich, the emperor's friends, and the large corporations. BUT those who need it the most will only get the crumbs. Who are the Republicans kidding?

I have coined two new Acronym's MOM and #LTCTOT. A clue: MOM is not about your mum. It is Master Of Misinformation --wonder who that is?  



CV-19 Blues Crush






Caveat Emptor ~ I may  really be in the weeds this go around. But, Hey, 20%  of the USA population are home bound so maybe we can collectively do it together.







Firstly I bought two of the QRP Labs Phase Shift Networks which are in route to me. I did a bit of further examination and there are two mods that will be required. (This is not a kit project!). The first issue is to decode how to connect to the inputs which I will need to pursue further study. But there are two other identified "hurdles".

The first hurdle aside from interconnection is that the PSN has a narrow band width of perhaps about 1500 Hz which will really piss off the 40 Meter FLEX Radio guys. But this 1st go around is proof of concept and then I will need to see how to make that wider.

The 2nd hurdle is that the PSN is not bidirectional -- it was made to chunk in a receiver. Use in a transmitter requires some significant modifications. So there is some electronics on the board that SUM the I and Q channels to produce an audio output for the receive mode. That part of the circuitry will have to be bypassed so it can feed the I and Q Channels on the RADIG Board. Now on the front end of the PSN we will have to build an interface that takes the single ended output of the 2N3904  Microphone amp and splits it into two signals to feed the input side of the PSN. My first thought would be to use something like a modem coupling transformer to create a balanced input. There likely will be development needed here.

So before you buy a set, you might want to see how I fare. But this is the fun and it is a time killer. I think that in about a week the total US will be in lockdown. 

I have tried to contact Hans Summers about these two issues and have not heard back --so I might try a different email.

So those of you who thought this was a hoax --we are here because the emperor (with a miniscule e) is in denial. The last thing anyone should do is believe him or any of his claims. #LTCTOT! In essence we are on our own and the emperor (with a microscopic e)  has written us off! So let us observe the safe practices and LBAPT!

73's
Pete N6QW

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