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Interesting how this gets mentioned.

Galaxy, at least in their EARLY years, did use 2 diodes along with and RF Switch (D33) to offset the downward forcing...

[ATTACH=full]60272[/ATTACH]

When you went to Channels below - Like BAND A and BAND B - C92 was used to pull down the tuning range D30 (additional) and D94 (Series-Lo-pass ripple filter SEE:AN612) - when the system needed to push up the tuning range - Bands C, D, and E - it was grounded out enabling it to work in PARALLEL with the Varactors output to help with linearity of the tuning range in the band to help out the PLL's incessant desire to "twang" - in specific instances of weak regulation and drift - when the PLL and the VCO loop on occasion would struggle to match and lock in -this helps offset the needed (or not needed) capacitance to "swing" the channels in the selected Band.

<blockquote data-quote="Handy Andy" data-source="post: 796883" data-attributes="member: 52309">Interesting how this gets mentioned.Galaxy, at least in their EARLY years, did use 2 diodes along with and RF Switch (D33) to offset the downward forcing...[ATTACH=full]60272[/ATTACH]When you went to Channels below - Like BAND A and BAND B - C92 was used to pull down the tuning range D30 (additional) and D94 (Series-Lo-pass ripple filter SEE:AN612) - when the system needed to push up the tuning range - Bands C, D, and E - it was grounded out enabling it to work in PARALLEL with the Varactors output to help with linearity of the tuning range in the band to help out the PLL&#039;s incessant desire to &quot;twang&quot; - in specific instances of weak regulation and drift - when the PLL and the VCO loop on occasion would struggle to match and lock in -this helps offset the needed (or not needed) capacitance to &quot;swing&quot; the channels in the selected Band.</blockquote>

[QUOTE="Handy Andy, post: 796883, member: 52309"] Interesting how this gets mentioned. Galaxy, at least in their EARLY years, did use 2 diodes along with and RF Switch (D33) to offset the downward forcing... [ATTACH type="full" alt="1661118217605.png"]60272[/ATTACH] When you went to Channels below - Like BAND A and BAND B - C92 was used to pull down the tuning range D30 (additional) and D94 (Series-Lo-pass ripple filter SEE:AN612) - when the system needed to push up the tuning range - Bands C, D, and E - it was grounded out enabling it to work in PARALLEL with the Varactors output to help with linearity of the tuning range in the band to help out the PLL's incessant desire to "twang" - in specific instances of weak regulation and drift - when the PLL and the VCO loop on occasion would struggle to match and lock in -this helps offset the needed (or not needed) capacitance to "swing" the channels in the selected Band. [/QUOTE]

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