Hi Ross,
My experience with all iron powder toroids is there are always
variations from toroid batch to batch, and actual? inductance can
vary quite a bit--one measures the final inductance and adjusts
turns and spacing to give the desired inductance.
73,
Steve AA7U
On 4/5/2025 1:49 PM, Ross Tucker (NS7F)
via groups.io wrote:
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Thanks for the feedback! Also, btw: the schematic
says L1 is 1.5 uH but 20 turns on a T50-2 is supposed to be 1.96
uH. Any thoughts on that?
On Sat, Apr 5, 2025 at 11:30
Steve Ratzlaff via <ratzlaffsteve=
[email protected]>
wrote:
Hi
Ross,
On mine, the Low band tunes 3.90-5.24 MHz; High band tunes
5.46-- ~19
MHz, as you note at least the High band is very wide tuning.
Your scheme
would probably work but I predict it will take a lot of
experimentation
to achieve it. Good luck and please let us know how it all
turns out.
73,
Steve AA7U
On 4/5/2025 8:10 AM, Ross Tucker (NS7F) via wrote:
> I am building an Ozark Patrol regen. The stock tuning
range is very large and I would like to limit it. By
default, there is a SPDT switch that adds a parallel
capacitance for a second range. My goal is to align the two
ranges with the 20 and 40 m bands.
>
> Math shows that I need two fixed capacitors (one in
series with the tuning, one in parallel with that) for each
band. My thought is to replace the SPDT with a DPDT. I would
build the circuit for 20 m and the switch poles would select
in the appropriate differences to each fixed capacitor.
>
> Does this seem reasonable? Is this how it's done?
>
>
>
>
>
