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Hi Nomadradio.

I tried the pin 10 where you cut the 5.120 signal to L19 and injected my own oscillator. I bought some 5.120 xtals from Ali Express and well I used one of my Expo S kit with the 5.120 xtal and it would generate the 5.120 signal but no adjustment in the trim cap to off set to move the channels down 10 kc.
I think the 5.120 xtals are not cut so that there is any adjustment.

Is there any better way to build a 5.120 oscillator to adjust to inject into L19 to get the 10KC jump?
I think if I could build an adjustable oscillator it might work.

Im looking for a fixed 10kc jump no slide.

Here is a post on using the 5.120 oscillator.

[EMBED content="thread-254962"]https://www.worldwidedx.com/threads/cobra-25-29-10k-slide-help.254962/[/EMBED]

Quote from Kopsicle>I'm guessing you don't completely understand the problem.
If you shift the 5.12 x 3 (15.360) signal of course what is presented to the filter will move . 5.116666667×3=15.350000001, 15.350000001+.91+10.695=26.955000001, then the filter "sees" is 15.350000001-10.695=4.655000001.
If you pull on the 10.240 reference it actually works a bit better because the 5.12 is derived from the 10.240 then multiplied by 3 to get 15.360 , the difference is still an issue, 10.2333333 / 2=5.11665 ×3 =15.34995 =5.11665.

thanks

<blockquote data-quote="dss56" data-source="post: 855463" data-attributes="member: 15057">Hi Nomadradio.I tried the pin 10 where you cut the 5.120 signal to L19 and injected my own oscillator. I bought some 5.120 xtals from Ali Express and well I used one of my Expo S kit with the 5.120 xtal and it would generate the 5.120 signal but no adjustment in the trim cap to off set to move the channels down 10 kc.I think the 5.120 xtals are not cut so that there is any adjustment.Is there any better way to build a 5.120 oscillator to adjust to inject into L19 to get the 10KC jump?I think if I could build an adjustable oscillator it might work.Im looking for a fixed 10kc jump no slide.Here is a post on using the 5.120 oscillator.[EMBED content=&quot;thread-254962&quot;]https://www.worldwidedx.com/threads/cobra-25-29-10k-slide-help.254962/[/EMBED]Quote from Kopsicle&gt;I&#039;m guessing you don&#039;t completely understand the problem. If you shift the 5.12 x 3 (15.360) signal of course what is presented to the filter will move . 5.116666667×3=15.350000001, 15.350000001+.91+10.695=26.955000001, then the filter &quot;sees&quot; is 15.350000001-10.695=4.655000001.If you pull on the 10.240 reference it actually works a bit better because the 5.12 is derived from the 10.240 then multiplied by 3 to get 15.360 , the difference is still an issue, 10.2333333 / 2=5.11665 ×3 =15.34995 =5.11665.thanks</blockquote>

[QUOTE="dss56, post: 855463, member: 15057"] Hi Nomadradio. I tried the pin 10 where you cut the 5.120 signal to L19 and injected my own oscillator. I bought some 5.120 xtals from Ali Express and well I used one of my Expo S kit with the 5.120 xtal and it would generate the 5.120 signal but no adjustment in the trim cap to off set to move the channels down 10 kc. I think the 5.120 xtals are not cut so that there is any adjustment. Is there any better way to build a 5.120 oscillator to adjust to inject into L19 to get the 10KC jump? I think if I could build an adjustable oscillator it might work. Im looking for a fixed 10kc jump no slide. Here is a post on using the 5.120 oscillator. [EMBED content="thread-254962"]https://www.worldwidedx.com/threads/cobra-25-29-10k-slide-help.254962/[/EMBED] Quote from Kopsicle>I'm guessing you don't completely understand the problem. If you shift the 5.12 x 3 (15.360) signal of course what is presented to the filter will move . 5.116666667×3=15.350000001, 15.350000001+.91+10.695=26.955000001, then the filter "sees" is 15.350000001-10.695=4.655000001. If you pull on the 10.240 reference it actually works a bit better because the 5.12 is derived from the 10.240 then multiplied by 3 to get 15.360 , the difference is still an issue, 10.2333333 / 2=5.11665 ×3 =15.34995 =5.11665. thanks [/QUOTE]

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