Author Topic: Sencore CB42 repair thread  (Read 10960 times)

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Sencore CB42 repair thread
« on: November 17, 2014, 08:16:28 PM »
This will be an upcoming repair thread on this unit
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Re: Sencore CB42 repair thread
« Reply #1 on: November 17, 2014, 08:45:03 PM »
Well there is a signal under all that noise.
Sitting at 26.919 MHZ
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Re: Sencore CB42 repair thread
« Reply #2 on: November 18, 2014, 05:09:05 PM »
10 volt to IF board
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Re: Sencore CB42 repair thread
« Reply #3 on: November 27, 2014, 08:10:29 AM »
RF/IF 5 volt regulators
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Re: Sencore CB42 repair thread
« Reply #4 on: November 27, 2014, 10:29:49 AM »
While testing the counter board (H) I found that the 10 MHz clock was not present.
I did verify that the crystal works by inserting it on my crystal tester.
Now to find what component in the osc circuit is not working.
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Re: Sencore CB42 repair thread
« Reply #5 on: November 27, 2014, 03:08:22 PM »
Closer, here I am generating a frequency on channel 20. But the display is not showing the frequency. But at least all 7 digits are running. And when changing channels what there changes on the display.
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Re: Sencore CB42 repair thread
« Reply #6 on: November 28, 2014, 03:31:47 PM »
Scope screen shot of IC211 pin 2
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Re: Sencore CB42 repair thread
« Reply #7 on: November 28, 2014, 03:32:44 PM »
bigger
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Re: Sencore CB42 repair thread
« Reply #8 on: November 28, 2014, 03:50:44 PM »
IC205 pin12
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Re: Sencore CB42 repair thread
« Reply #9 on: December 07, 2014, 09:20:02 AM »
Here is a block diagram
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Re: Sencore CB42 repair thread
« Reply #10 on: December 07, 2014, 09:20:45 AM »
try to upload a bigger image
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