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Project #2 -- Colpitts Crystal Oscillator

 

Ready for prime time.



is the video of how I built and tested the Colpitts Crystal Oscillator using the
PCB that I am labeling K7QO-001.2 as version 2 of the circuit.

The video pretty well covers all the values and options for the build.
Remember.? The purpose of this exercise is for you to experiment with
the component values as they are not locked down.? The Colpitts oscillator
works well with a wide range of component values.? Been there.? Done that.

In [email protected] directories are two directories associated with this project.

Winter 2018 Project #2 -- Colpitts oscillator.? The files starting with K7QO-001
are the Gerber files in the .zip and an image from layout 6.0 of the board is jpg file.

K7QO PCB 001 -- Colpitts Crystal Oscillator directory with Gerber
files in k7qo-001.zip to upload to allpcb.com or PCB company of
your choice.

No values are given on the board so that you won't feel locked into the values.
In the video I show the schematic as it evolves.? All diodes are 1N4148 in my
build.? If you feel the need to use 1N34As in the voltage doubler, be my guest.
I don't think it is necessary and I can do the math if necessary for your
edification.

---------------------------------------------IMPORTANT--------------------------------------

May I suggest the following?? Form a local group in your county and surrounding
reasonable driving time and distance to a restaurant that has a gathering area
of several tables.? You may have to start small, but every journey starts with
a single step.? Scour the country side for interested parties.

Meet once a month.? Some one buy 10 boards for a project and distribute them.
Then for the next month some one else buys the next round.? And so on.

Work together on soldering skills, parts accumulation and finding, and all
the other issues that come up.? Help each other.

Do show and tells on things that work and things that don't.? We learn more from
things that go wrong than from easy successes.? Help those that ask for help.
Ask for help when you need it.

You create new friendships and gain in the fun of sharing locally. Over the Internet
has its place, but I enjoy the Thursday breakfast club locally for sharing.? Passing
projects around is more fun that looking at online photos.? IMHO.

Start the building.? Several projects to chose from now and more to come in the
months to follow.? Surely you can enjoy some of these no matter how long you
have been a ham.? I really enjoy the small projects as much as the big ones.

FYI and cheers,

chuck, k7qo
Doug Hendricks
 

Chuck, some guys will think what am I going to do with 10 boards? I only need 1. Guess I could give them to my friends, but I only have 1, what do I do with the other 8 boards?

You are wrong my friend, you need 5 boards.

1. Board built with socket for matching crystals.
2. Build board with 80 meter crystal for 80 meter signal generator.
3 - 5. Build boards for 40, 30 and 20 meter signal generators.

So you do need 5 boards and one lucky friend.

Very useful project. Doug, KI6DS
William
 

Chuck,

The Crystal Checker board looks interesting and I am attempting to place an order with ALLPCB but cannot seem to find where/how the Gerber .zip archive should be uploaded. If you or others will point that out in a tad more detail, I would be obliged.

Thank you.
--
William, K6WHP
"Cheer up, things could get worse..so I cheered up and, sure enough, things got worse!"
 

Here are the steps as I see them.? Hopefully I will get this right and it works for you.

0.? Download to your computer system the .zip file that has the Gerber files in it.
Do not unzip.

1.? Register with allpcb by going to www.allpcb.com/G6.? The G6 gets you to our
rep for counting qrp-tech orders.? I don't get a kickback.? It will help, hopefully,
get us special order pricing in the future.

2.? When you log in, in the upper left of the page you will see an
'Instant Quote' button.? Select it.? This will bring up a page with a
lot of selections.

Go to the third line and enter the dimensions of the board.

Go to the next line and select 10.

You should see immediately a price of $5 appear on the right.

Go down to the 'Add to Cart' and select.

Another page will appear and a window will pop up in the middle to
upload the Gerber file.? Move mouse over the grey area that says
Add Gerber File and has a large + sign in the middle and click.
Then you move around your local file system to get to the Gerber file.
You'll see C:\fakepath\k7qo-001.zip if you are doing the Colpitts project.

Then just Submit Order Now.

New page appears with your shopping cart and you select Buy and
then pay with paypal, if that is your choice.

Hope that makes it easy for all to follow.

chuck, k7qo

On 11/24/2017 10:26 PM, William wrote:
Chuck,

The Crystal Checker board looks interesting and I am attempting to place an order with ALLPCB but cannot seem to find where/how the Gerber .zip archive should be uploaded. If you or others will point that out in a tad more detail, I would be obliged.

Thank you.
 

How would we know the size of the board?

Lee, w0vt

On 11/24/2017 11:48 PM, chuck adams wrote:
Here are the steps as I see them.? Hopefully I will get this right and it works for you.

0.? Download to your computer system the .zip file that has the Gerber files in it.
Do not unzip.

1.? Register with allpcb by going to www.allpcb.com/G6.? The G6 gets you to our
rep for counting qrp-tech orders.? I don't get a kickback.? It will help, hopefully,
get us special order pricing in the future.

2.? When you log in, in the upper left of the page you will see an
'Instant Quote' button.? Select it.? This will bring up a page with a
lot of selections.

Go to the third line and enter the dimensions of the board.

Go to the next line and select 10.

You should see immediately a price of $5 appear on the right.

Go down to the 'Add to Cart' and select.

Another page will appear and a window will pop up in the middle to
upload the Gerber file.? Move mouse over the grey area that says
Add Gerber File and has a large + sign in the middle and click.
Then you move around your local file system to get to the Gerber file.
You'll see C:\fakepath\k7qo-001.zip if you are doing the Colpitts project.

Then just Submit Order Now.

New page appears with your shopping cart and you select Buy and
then pay with paypal, if that is your choice.

Hope that makes it easy for all to follow.

chuck, k7qo


On 11/24/2017 10:26 PM, William wrote:
Chuck,

The Crystal Checker board looks interesting and I am attempting to place an order with ALLPCB but cannot seem to find where/how the Gerber .zip archive should be uploaded. If you or others will point that out in a tad more detail, I would be obliged.

Thank you.
 

In the Files section look at the description for "K7QO PCB 001 -- Colpitts Crystal Oscillator" and you will see it says dimensions are 50 mm x 50 mm
 

OK, I got ten Project 2 Colpitts boards ordered.? I looked at your video and you said the proto board was 5 cm.? Using this,? I ordered the boards putting in 50 mm for both dimensions.? I was able to check out for $5.00.? Job done.
Lee, w0vt
William
 

..as Lee did, so did I. Thanks, Chuck! The instructions were dead on!
--
William, K6WHP
"Cheer up, things could get worse..so I cheered up and, sure enough, things got worse!"
 

Yep! Worked for me too. Says I have ten on the way. :)
Larry
KA5T

On Nov 25, 2017, at 12:53 PM, William <k6whp@...> wrote:

..as Lee did, so did I. Thanks, Chuck! The instructions were dead on!
...
 

Would there be any benefit to adding a buffer amplifier between the oscillator and the counter?

Thank you.

Jim Pruitt
WA7DUY

On 11/24/2017 6:34 PM, chuck adams wrote:
Ready for prime time.



is the video of how I built and tested the Colpitts Crystal Oscillator using the
PCB that I am labeling K7QO-001.2 as version 2 of the circuit.

The video pretty well covers all the values and options for the build.
Remember.? The purpose of this exercise is for you to experiment with
the component values as they are not locked down.? The Colpitts oscillator
works well with a wide range of component values.? Been there. Done that.

In [email protected] directories are two directories associated with this project.

Winter 2018 Project #2 -- Colpitts oscillator.? The files starting with K7QO-001
are the Gerber files in the .zip and an image from layout 6.0 of the board is jpg file.

K7QO PCB 001 -- Colpitts Crystal Oscillator directory with Gerber
files in k7qo-001.zip to upload to allpcb.com or PCB company of
your choice.

No values are given on the board so that you won't feel locked into the values.
In the video I show the schematic as it evolves.? All diodes are 1N4148 in my
build.? If you feel the need to use 1N34As in the voltage doubler, be my guest.
I don't think it is necessary and I can do the math if necessary for your
edification.

---------------------------------------------IMPORTANT--------------------------------------


May I suggest the following?? Form a local group in your county and surrounding
reasonable driving time and distance to a restaurant that has a gathering area
of several tables.? You may have to start small, but every journey starts with
a single step.? Scour the country side for interested parties.

Meet once a month.? Some one buy 10 boards for a project and distribute them.
Then for the next month some one else buys the next round.? And so on.

Work together on soldering skills, parts accumulation and finding, and all
the other issues that come up.? Help each other.

Do show and tells on things that work and things that don't.? We learn more from
things that go wrong than from easy successes.? Help those that ask for help.
Ask for help when you need it.

You create new friendships and gain in the fun of sharing locally. Over the Internet
has its place, but I enjoy the Thursday breakfast club locally for sharing.? Passing
projects around is more fun that looking at online photos.? IMHO.

Start the building.? Several projects to chose from now and more to come in the
months to follow.? Surely you can enjoy some of these no matter how long you
have been a ham.? I really enjoy the small projects as much as the big ones.

FYI and cheers,

chuck, k7qo
 

I ordered Chuck's boards for the Oscillato from Allpcb late Friday evening.? I checked their site this morning, Sunday morning,? and the boards have been fabricated and ready to ship.? They must work 24/7.

Lee, w0vt
 

Hi Jim,

well, I did build the CCO Chuck is showing on page 112 of his great QRP Lab Notebook V.6.31. This original G3UUR design is very stable with the second transistor as a buffer stage.
By connecting a f-counter to the circuit you are taking away energy from it. So a buffer stage makes sense and I think it makes sense.

When I put the xtals in the holder am not only locking for the f reading. No further more I am using the original G3UUR CCO to determine f under the extra C load and to read out the Xtal amplitude voltage.
By looking at this voltage you are able to make a quantitive statement about the Q of the quartz.

When putting all number in a spread sheet I filter first after the quartz oscillator amplitude voltage (Q) than I look for the unloaded f and than I have a closer look at the loaded f reading.
Maybe I am a bit wrong with this.

I was reading quite a lot the last days about xtals filters. Maybe too much ... But hey this is what this project is all about .... Asking questions and lear from each other.

I am totally satisfied with the Manhattan style build of the original G3UUR circuit with the buffer stage and the extra switch plus C load.
Try it G3UUR Manhattan style and than compare it to the reduced version.

Good luck..... and thanks for all that ?trouble¡° on my workbench

72/3`s de sTef - DM5TU / VY1QRP - DL-QRP-AG *GM* - GQRP #8769 - CalQRP #034 - NAP #1607
 

I just ordered ten boards from my new friends at allpcb. They must have a pretty good marketing budget to absorb all the DHL charges!

I am building the colpitts circuit from K7QO's notebook manhattan style and I will build one or more of the PCB version to compare them. I think the colpitts PCB will be the first one I offer as an inducement in my never ending effort to get a local builders group started.

73 de bill K7WXW
CN85qm
________
specialization is for insects. - r.a. heinlein

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