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I wanted to post an update now that I have some new tools in my arsenal. I acquired a Tektronix 2236 oscilloscope and it has proven to be helpful. I was able to confirm several things that I observed with the VNA.

The internal frequency counter on the scope is extremely helpful and is close if not on. I used the scope to adjust all of the slugs to their maximum. I confirmed the 19.70378 signal is coming to V11 from the first 2 sets of crystals. I also confirmed the 7.5 MHz crystal reads 7.25 just like the VNA. Also just like the VNA, pulling the 7.5 MHz crystal out of the radio will still give you the 7.25 MHz signal and....get this....you can adjust the frequency and height of the sine wave with the slug for the crystal while the crystal is completely removed. I'm not sure how that's possible but that's the case. I tried 2 different crystals with the same result.

Lastly I confirmed that if you key the radio with the scope probe on the output of the final slug adjustment you get a 26.9526 frequency which is exactly the .250ish low from the 7.5 MHz crystal. I was on channel 20 - 27.205 at the time. You get this whether the crystal is in or out.

Any insight or guidance on any of this would be greatly appreciated. Thank you.

<blockquote data-quote="Champo" data-source="post: 779628" data-attributes="member: 60887">I wanted to post an update now that I have some new tools in my arsenal. I acquired a Tektronix 2236 oscilloscope and it has proven to be helpful. I was able to confirm several things that I observed with the VNA.The internal frequency counter on the scope is extremely helpful and is close if not on. I used the scope to adjust all of the slugs to their maximum. I confirmed the 19.70378 signal is coming to V11 from the first 2 sets of crystals. I also confirmed the 7.5 MHz crystal reads 7.25 just like the VNA. Also just like the VNA, pulling the 7.5 MHz crystal out of the radio will still give you the 7.25 MHz signal and....get this....you can adjust the frequency and height of the sine wave with the slug for the crystal while the crystal is completely removed. I&#039;m not sure how that&#039;s possible but that&#039;s the case. I tried 2 different crystals with the same result.Lastly I confirmed that if you key the radio with the scope probe on the output of the final slug adjustment you get a 26.9526 frequency which is exactly the .250ish low from the 7.5 MHz crystal. I was on channel 20 - 27.205 at the time. You get this whether the crystal is in or out.Any insight or guidance on any of this would be greatly appreciated. Thank you.</blockquote>

[QUOTE="Champo, post: 779628, member: 60887"] I wanted to post an update now that I have some new tools in my arsenal. I acquired a Tektronix 2236 oscilloscope and it has proven to be helpful. I was able to confirm several things that I observed with the VNA. The internal frequency counter on the scope is extremely helpful and is close if not on. I used the scope to adjust all of the slugs to their maximum. I confirmed the 19.70378 signal is coming to V11 from the first 2 sets of crystals. I also confirmed the 7.5 MHz crystal reads 7.25 just like the VNA. Also just like the VNA, pulling the 7.5 MHz crystal out of the radio will still give you the 7.25 MHz signal and....get this....you can adjust the frequency and height of the sine wave with the slug for the crystal while the crystal is completely removed. I'm not sure how that's possible but that's the case. I tried 2 different crystals with the same result. Lastly I confirmed that if you key the radio with the scope probe on the output of the final slug adjustment you get a 26.9526 frequency which is exactly the .250ish low from the 7.5 MHz crystal. I was on channel 20 - 27.205 at the time. You get this whether the crystal is in or out. Any insight or guidance on any of this would be greatly appreciated. Thank you. [/QUOTE]

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