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Re: 2n2xx Transceiver R.I.P.

 



On Sat, Dec 14, 2019, 11:43 AM Jerry Gaffke via Groups.Io <jgaffke=[email protected]> wrote:

Nothing in my rather short list of scruples says you shouldn't be getting paid $5/hr for your efforts.

Jerry, KE7ER

Ack! Not me! I have a day job :)

Do you know what the power supply current requirements would be for the synthesizer, LCD and Arduino? I still marvel at my SW40+ that uses only 25mA on receive.

I think it would be fun to build this up with modules. Each module / function would be fairly easy dead-bug style, then connect the bits and test.?

Mike M
Ku4qo
Re: For Sale: Norcal 40a

 

Sold.
Re: What level math is in the RF design books?

Rob
 

开云体育

thank you


On 12/14/2019 08:00 AM, Ramakrishnan Muthukrishnan wrote:

Rob --

If you have a copy of "Experimental Methods of RF Design", take a look at chapter 2 "Amplifier Design Basics", first few pages, which discusses simplified models of semiconductor devices. I think that level of intuition is great to have while building and debugging circuits. It does not have a lot of advanced math.

73
Ram VU3RDD

On Mon, Dec 9, 2019, at 5:47 PM, Rob via Groups.Io wrote:
What level of math course would I need to study to learn how to comprehend the equations presented in
design books like Introduction to Radio Frequency Design?? by? W7ZOI.

I have been tinkering with circuits from these books for 50 years but never really learned what is in the math.

There are all sorts of online math course now so.....

What level of math class would teach this gobbledygoop?

and

Do any of you? ACTUALLY use this level of math to build radios or is the math only used by
the guys designing the transistors????





73 Rob KB3BYT




Attachments:
  • math0.jpg

--
Ramakrishnan
Re: 2n2xx Transceiver R.I.P.

 

I can see where Jim would rather not have us copy his gerbers,
Hundreds of folks will know that he did the design, and a few
will inevitably pester him for help.?

If stealing a significant part of the design such as the receiver core?
but putting in an si5351, different audio amp, different final,?
he may or may not be ok with that.? Ask.

Borrowing the topology of an especially nice IF stage in your new design,
that sort of thing is often done without any atrribution.

A slippery slope.

And a very compelling design, especially in this age of designs
mostly locked down in DSP firmware.

Jerry, KE7ER
Re: 7 MHz Oscillator Ideas

 

Chuck,

I think we all agree that your design will be plenty stable.
It is crystal controlled, going from zero to 12v on the bias for the varactor that is
in parallel with the crystal can only move the frequency by 2 or 3 khz.

What we are saying is that for most such designs where the varactor might be trying to
give a range of 300khz instead of 3khz, the stability will be 100 times worse than what you experience.
And so it won't work very well unless the power supply that provides the bias across the varactor is well regulated.

You have noted that the capacitance of the varactor does not change much for a 1 volt change in the 12v power supply.
If the bias across the varactor is reduced from 12v to 1v by turning the pot, then a 1 volt change in the 12v supply
will cause a 1/12 volt change in the 1 volt bias across the varactor.
Which doesn't sound like much, but the varactor is much more sensitive to changes in bias voltage at 1v than at 12v.

Jerry, KE7ER



On Sat, Dec 14, 2019 at 05:49 AM, Chuck Carpenter wrote:
Nick,

I've made some measurements using the?SA612?oscillator in my WWV +?30m receiver.
The crystal is a single, 10 MHz nominal.? Keep in mind that this is a simple DC receiver and may not meet the specs for a $5k buck rig.

I'm using a fairly well regulated bench power supply.? Not a cheap 9V battery that sags quickly under?load.

So are we saying that the DC supply to the receiver is drifting plus and minus several mV?? And that would significantly change the oscillator tuning?

Or is the power supply stable within a few mV?? And that it stays at the set voltage unless deliberately changed.

I'm measuring the oscillator frequency via gimmick with set voltages at 10, 12 and 14. I've measured the output of the 5V regulator to the SA-612 with no significant change at each set voltage.

With both O'scope and DVM?on most sensitive levels, there is no significant DC voltage?ripple.

Yes, the highest?tuned?frequency changes at each of the set voltages.? BUT is doesn't change?once set!

So unless the set voltages are changed, I doubt that anyone, by ear, could detect any change while listening to a specific station, e.g., WWV-10MHz with test RX.

And I have done that with the RX I built, both WWV and CW station on 30 m.

--
Chuck, W5USJ (ex K2OFN)
Point, Rains Co, TX? EM22cv
Re: 2n2xx Transceiver R.I.P.

 

Agreed Mike.? Good to hear from you again.? Jim just doesn't want a mass distribution.? Note that he encourages builders to make their "OWN PCB".? I agree that it was an amazing design.? Jim is one of the great designers of qrp gear and a good friend.? Doug, KI6DS
Re: 2n2xx Transceiver R.I.P.

 

Rob there is no problem with anyone making their own board for their own use, it is the distribution of those boards that is the thing that I object to.? Jim does not want to not does he have the time to do the support that a distribution of boards would surely cause.? He has made his wishes clear, please respect them.??
Re: 2n2xx Transceiver R.I.P.

 

The use of ADE-1 (or SBL-1) diode ring mixers make it possible for the receiver?
to have a very large dynamic range.? It also makes it possible for the receiver
to suck down the battery much more easily than the usual SA612's.

I'm thinking I should build up the receiver core, at least.
Looking at the 40m version, I'd build out the RF filter at L5,L8,? and everything
between mixers M2 and M1 inclusive.? There is a lot to be learned by studying,
simulating, and tinkering with that part of the rig.

Nothing special in the audio amp.? Many designs these days would use an op amp
and an LM386.? Though Jim's PN2222 amp might be lower distortion than an LM386.?

Q20 and all those 1n4148's could be replaced with just an RF gain pot at the antenna.
Q20 would be useful for muting if this is to be used with a transmitter.

Two channels of an Si5351 could replace the VFO (Q24 through T5) and the RX LO (at X5,Q11).?
That's a major win on stability, flexibility, and ease of construction.
Assuming you're ok with soiling your analog design with a bunch of digital stuff.

The Si5351 VFO can flip to the operating frequency if including a transmitter,
doing away with the oscillator, mixer, and filter at X8, M3, and T8.?
The entire power amp from Q19 to Q25 could be replaced with many other possible designs.?

So building this thing could be very ad-hoc, using what you have,?done step by step.?
Lots of kits out there for audio amps and transmit power amps if you want to cheat.
The Si5351 could be a module from etherkit, adafruit,?qrplabs, or?the ubitx raduino.

No need to demand that Jim come out of retirement to fab a board for you.
The 2n22xx has no IC's, should be easy to build ugly or manhatten style.?
? ?
VU3JVX shows off a beautiful scratch built uBitx
? ??/g/BITX20/topic/68158902#73506
built by creating copper islands using a 5/16 inch "spot weld drill bit" such as
? ???
Those same bits can be used to create manhatten pads if you press a little harder.

>? It seems that he has no problem with copying the design or modifying it, along with creating a pcb.
>? Obviously it would be immoral to profit from it.?

If somebody wants to make available a 2n22xx kit and is ready to fully support it,?
perhaps you should just ask Jim.? He might well be delighted to give his blessing.
So long as he doesn't have to answer the phone.
Nothing in my rather short list of scruples says you shouldn't be getting paid $5/hr for your efforts.

Jerry, KE7ER


On Sat, Dec 14, 2019 at 03:54 AM, Michael Maiorana wrote:
Doug,
From Jim's email on November 10th:
?
Finally, all of the documentation for the 2N2/XX is on my web site:??(??) so you can get the docs, build any of the 3 bands Manhattan-style, like I did originally, or make your own PCB using DipTrace or KiCAD with the changes you see fit (like DDS tuning and Digital Display) on a PCB sized to your liking.

It seems that he has no problem with copying the design or modifying it, along with creating a pcb. Obviously it would be immoral to profit from it.?
?
I remember when I first saw that design and how amazed I was at what he accomplished within the (arbitrary) confines of the contest. Amazing work!
?
Best regards and 73
Mike M?
Ku4qo
Re: 7 MHz Oscillator Ideas

 

Nick,

I've made some measurements using the?SA612?oscillator in my WWV +?30m receiver.
The crystal is a single, 10 MHz nominal.? Keep in mind that this is a simple DC receiver and may not meet the specs for a $5k buck rig.

I'm using a fairly well regulated bench power supply.? Not a cheap 9V battery that sags quickly under?load.

So are we saying that the DC supply to the receiver is drifting plus and minus several mV?? And that would significantly change the oscillator tuning?

Or is the power supply stable within a few mV?? And that it stays at the set voltage unless deliberately changed.

I'm measuring the oscillator frequency via gimmick with set voltages at 10, 12 and 14. I've measured the output of the 5V regulator to the SA-612 with no significant change at each set voltage.

With both O'scope and DVM?on most sensitive levels, there is no significant DC voltage?ripple.

Yes, the highest?tuned?frequency changes at each of the set voltages.? BUT is doesn't change?once set!

So unless the set voltages are changed, I doubt that anyone, by ear, could detect any change while listening to a specific station, e.g., WWV-10MHz with test RX.

And I have done that with the RX I built, both WWV and CW station on 30 m.

--
Chuck, W5USJ (ex K2OFN)
Point, Rains Co, TX? EM22cv
Re: What level math is in the RF design books?

 

Rob --

If you have a copy of "Experimental Methods of RF Design", take a look at chapter 2 "Amplifier Design Basics", first few pages, which discusses simplified models of semiconductor devices. I think that level of intuition is great to have while building and debugging circuits. It does not have a lot of advanced math.

73
Ram VU3RDD

On Mon, Dec 9, 2019, at 5:47 PM, Rob via Groups.Io wrote:
What level of math course would I need to study to learn how to comprehend the equations presented in
design books like Introduction to Radio Frequency Design?? by? W7ZOI.

I have been tinkering with circuits from these books for 50 years but never really learned what is in the math.

There are all sorts of online math course now so.....

What level of math class would teach this gobbledygoop?

and

Do any of you? ACTUALLY use this level of math to build radios or is the math only used by
the guys designing the transistors????





73 Rob KB3BYT




Attachments:
  • math0.jpg

--
Ramakrishnan
Re: 2n2xx Transceiver R.I.P.

 

Doug,
From Jim's email on November 10th:

Finally, all of the documentation for the 2N2/XX is on my web site:??(??) so you can get the docs, build any of the 3 bands Manhattan-style, like I did originally, or make your own PCB using DipTrace or KiCAD with the changes you see fit (like DDS tuning and Digital Display) on a PCB sized to your liking.

It seems that he has no problem with copying the design or modifying it, along with creating a pcb. Obviously it would be immoral to profit from it.?

I remember when I first saw that design and how amazed I was at what he accomplished within the (arbitrary) confines of the contest. Amazing work!

Best regards and 73
Mike M?
Ku4qo

On Sat, Dec 14, 2019, 1:03 AM Doug Hendricks <ki6ds1@...> wrote:
Rob, the 2N22 is the intellectual property of Jim Kortge.? He has asked that it not be made available.? Please honor his wishes and stop promoting this project.? It would be wrong for anyone to layout their own board and distribute it to anyone.? I would hope that such an idea would NOT be allowed on this list.? Flame suit on.? Doug, KI6DS

Re: 2n2xx Transceiver R.I.P.

Rob
 

开云体育

OK..no problem.

My point of view was that it is a well documented hands on DIY project transceiver

worthy of hand crafting for yourself..... not any money making ventures....

and since I learned how to kitchen etch PCBs I have learned much much much more about radio building.

I was not real successful with with my manhatten radio building.

So when I learned how to take a schematic and turn it into a PCB in my kitchen I began a steady stream of

very rewarding hobby electronics projects and I always shared HOW to do this stuff because there is no HEATHKIT

or RADIO SHACK to make it easy to want to play with the hobby of radio electronics.....

which tends to push newbies into the appliance operator ...instead of tinkerer... category.....

which leads to addictions like FT8.





On 12/13/2019 08:59 PM, Doug Hendricks wrote:

Rob, the 2N22 is the intellectual property of Jim Kortge.? He has asked that it not be made available.? Please honor his wishes and stop promoting this project.? It would be wrong for anyone to layout their own board and distribute it to anyone.? I would hope that such an idea would NOT be allowed on this list.? Flame suit on.? Doug, KI6DS

Re: 2n2xx Transceiver R.I.P.

 

Rob, the 2N22 is the intellectual property of Jim Kortge.? He has asked that it not be made available.? Please honor his wishes and stop promoting this project.? It would be wrong for anyone to layout their own board and distribute it to anyone.? I would hope that such an idea would NOT be allowed on this list.? Flame suit on.? Doug, KI6DS
Re: 2n2xx Transceiver R.I.P.

Rob
 

开云体育

NO WAY

The project is only dead if you want to leave it resting.

All of the wealth of documentation is there to make the 2n2xx tranceiver on ANY base you want... island pads... manhatten ...

or

PRINT YOUR OWN CIRCUIT BOARDS

which I highly recommend you do because you can spread out the parts and resize for your own tastes.

There really is no secret here. Use GIMP to draw black and white line art.

Simply trace all schematic lines with a fat paint brush and draw all components like you see from a birds eye view.

here is an example of a PIXIE coming to life:


Etched on kitchen table.


the wet works in more detail here:

and if you MUST have China fabricate a few hundred PCBs for a massive club build project you can

easily convert YOUR black and white line art to GERBER files.



Have fun.



On 12/13/2019 06:20 PM, Leland L. Bahr wrote:

The designer has voiced he does not want to offer a board.? The project is dead.

Lee, w0vt

On 12/13/2019 3:50 PM, ohwenzelph via Groups.Io wrote:
i would like (at least) one
jerry aa1of
franconia nh

Re: 2n2xx Transceiver

 

开云体育

The designer has voiced he does not want to offer a board.? The project is dead.

Lee, w0vt

On 12/13/2019 3:50 PM, ohwenzelph via Groups.Io wrote:

i would like (at least) one
jerry aa1of
franconia nh

Re: 2n2xx Transceiver

 

i would like (at least) one
jerry aa1of
franconia nh
Re: 2n2xx Transceiver

 

Steve, if the Chinese wanted to copy it, they would do it gerbers or no.? If I were the designer, I would be more concerned about having to support the builders if I produced new boards.? One way around this is to put the board on OshPark as a shared pcb.? That way, the gerbers are not downloadable, but are useable by someone who wants to build the project.? This will be more expensive per board than getting a 100 boards built in China, but much more protective.? Dale

On Fri, Dec 13, 2019 at 9:06 AM sigcom1 <sigcom@...> wrote:
You can look back through the message subject for the details.
The designer of the 2N2-XX chose not to release the Gerber file for the PCB.
Frankly, I wholeheartedly stand behind his decision.

73.......Steve Smith WB6TNL

"What's the status of this? I would be interested in this as well."



--
Dale Hardin
Elberta, AL?
Re: 2n2xx Transceiver

 

I cut my gums on 741's and 2222's.? Put down for a couple.? Thanks, Howard, n3fel
Re: 2n2xx Transceiver

 

You can look back through the message subject for the details.
The designer of the 2N2-XX chose not to release the Gerber file for the PCB.
Frankly, I wholeheartedly stand behind his decision.

73.......Steve Smith WB6TNL

"What's the status of this? I would be interested in this as well."
Re: 2n2xx Transceiver

 

What's the status of this? I would be interested in this as well.
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