Hi Lee,
Well, I would have called it quantization, or resolution, or minimum
step size. Anyway I know what you mean when you say granularity. However
I think that would make it difficult to get a perfect 1:1 SWR on the
transceiver side, even with the antenna side having a fairly low (like
3:1) SWR. And I would not expect that to limit how big the SWR is that
it can match. Maybe on 6 meters they put another capacitor in series
with the binary switched capacitors, resulting in both a smaller minimum
step size and a smaller maximum total capacitance. As you get up to 10
meters and above, losses in coax due to high SWR get much worse, so you
really want lower than 3:1 on the antenna side of the matching unit
anyway. This 3:1 matching limit on 6 meters is therefore not something I
would call a problem. I was just curious about why the limit is at six
meters instead of at 160 meters.
I think you actually get two to the seventh or eighth power (128 or 256)
values switching 7 or 8 fixed capacitors (or groups of paralleled
capacitors)in or out, rather than only 7 or 8 values.
DE N6KB
wa3fiy@radioadv.com wrote:
The limited matching range on 6 meters may have to do with the granularity
of the L and C both of which are comprised of fixed values switched into the
network binary fashion. One of my Ten Tec built-in tuners has 8 values of
each and a LDG tuner in my Orion Classic has 7 values of inductance and
8 capacitance.
Anyway, that's my guess, granularity.
73,
-Lee-
On 6 Aug 2006 at 10:47, Ken Brown wrote:
I would expect the tuner capability to be limited on 160 meters, because
larger values of capacitance and inductance would be needed there. Why
would there be any difficulty tuning up to 10:1 SWR on 6 meters?
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