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CB Tricks was the place for a long time.

RF Parts sells the 1:9 toroid from old Pride stock so I ordered one plus an assortment of fixed, factory-made inductors. I can also wind my own as I try to copy the Pride input but for 2 tubes. As for the Pride RF Input, there’s a lot to respect given how the Resistive padding runs parallel to band-switched inductors, because:

The swamping resistance (from two 1500Ω 2w resistors in Parallel) sums to 750Ω not the 450Ω the 1:9 toroid (50 to 450) is looking for. To get 750Ω down to 450Ω a whopping 1125Ω is needed. Very little resistance from the switched inductors so what brings the 750 down to 450?
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EDIT: Apparently, I need to factor in the resistance of each of the 4 inductors for 10/11, 20, 40, 80)
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IDK yet but it brings the added inquiry of what affect will come from 2 tubes instead of 1? The 300a's should be close enough to work with Nomad's 250b/Pride uH specs.

I will copy those inductance values and report back. Some use value from your efforts. Nomad, you contribute a lot to the Amateur community, thank you.

<blockquote data-quote="Naysayer" data-source="post: 840722" data-attributes="member: 57429">CB Tricks was the place for a long time.RF Parts sells the 1:9 toroid from old Pride stock so I ordered one plus an assortment of fixed, factory-made inductors. I can also wind my own as I try to copy the Pride input but for 2 tubes. As for the Pride RF Input, there’s a lot to respect given how the Resistive padding runs parallel to band-switched inductors, because:The swamping resistance (from two 1500Ω 2w resistors in Parallel) sums to 750Ω not the 450Ω the 1:9 toroid (50 to 450) is looking for. To get 750Ω down to 450Ω a whopping 1125Ω is needed.&nbsp; Very little resistance from the switched inductors so what brings the 750 down to 450?----------EDIT: Apparently, I need to factor in the resistance of each of the 4 inductors for 10/11, 20, 40, 80)----------IDK yet but it brings the added inquiry of what affect will come from&nbsp; 2 tubes instead of 1?&nbsp; The 300a&#039;s should be&nbsp; close enough to work with Nomad&#039;s 250b/Pride uH specs.I will copy those inductance values and report back.&nbsp; Some use value from your efforts.&nbsp; Nomad, you contribute a lot to the Amateur community, thank you.</blockquote>

[QUOTE="Naysayer, post: 840722, member: 57429"] CB Tricks was [I]the[/I] place for a long time. RF Parts sells the 1:9 toroid from old Pride stock so I ordered one plus an assortment of fixed, factory-made inductors. I can also wind my own as I try to copy the Pride input but for 2 tubes. As for the Pride RF Input, there’s a lot to respect given how the Resistive padding runs parallel to band-switched inductors, because: The swamping resistance (from two 1500Ω 2w resistors in Parallel) sums to 750Ω not the 450Ω the 1:9 toroid (50 to 450) is looking for. To get 750Ω down to 450Ω a whopping 1125Ω is needed. Very little resistance from the switched inductors so what brings the 750 down to 450? ---------- [B]EDIT: [/B]Apparently, I need to factor in the resistance of each of the 4 inductors for 10/11, 20, 40, 80) ---------- IDK yet but it brings the added inquiry of what affect will come from 2 tubes instead of 1? The 300a's should be close enough to work with Nomad's 250b/Pride uH specs. I will copy those inductance values and report back. Some use value from your efforts. Nomad, you contribute a lot to the Amateur community, thank you. [/QUOTE]

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