Dual oscilator board

[Radio Tech]

Ok, been playing around with a few circuits over the past few days for my Cobra 29 NW ST. I used some old A+ kits and did not like what I saw with them. Had a problem with mixing. When transmiting on low 20 there was a spike on normal 20.

So I built a dual crystal board. Lift C87 up and tied directly to it. This disables L22. Used the 9/19/normal switch to reinstall C87 back and to switch the 8 volts to each side of the board.

This sure worked better than any kit I have ever used. And the wattage did not drop from one end to the other.
I dont know if there is another one built like this on the market. I have not seen it if there is. But have been out of it for a few years.

 

[ExitThirteen]

Tag, good info here!



-Exit

 

[Radio Tech]

Thanks

 

[seedkey]

yup, good work

 

[Radio Tech]

As soon as my wife gets better (been in and out of hospital for a month), I will put together a file to print out the circuit board layout.

 

[seedkey]

That would be great. Where did you get the crystals? take them from an A+ kit?

 

[Radio Tech]

The 14 mhz crystals I have came from some older radios. Mixer crystals.
Although you can use the ones from the A kits.

 

[Radio Tech]

Here is the layout to print on your copper boards.
This layout uses Pad2Pad circuit board design program.
You can down load it here:
Printed Circuit Board Manufacturer for all your PCB needs

Install p2p. Unzip the boaard layout right into the director.

 

[seedkey]

Nice!!
now maybe a parts placement?

 

[Radio Tech]

Working on that and also it will show the drilled hole location.
Also a parts list with location.

 

[Radio Tech]

bump

 

[Radio Tech]

Here is the proto type made years ago.