KX1 on 17 meters?

[wd4lst-2]

Hello to all. I have been on the fence for a KX1 for a while
now, and am close to taking the plunge. My trusty HW-8 is pretty bulky in a backpack. I was wondering if anyone has considered a 17 meter option. I would gladly exchange 20 or 80 for 17.
Thanks and 73s,
Pete
wd4lst

Pete Axson
WD4LST
17901 NE 18th Ave
Citra, FL 32113

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[Mike Morrow-3]

>I was wondering if anyone has considered a 17 meter option.

The clocking rate of the KX1's AD9834 DDS chip is 50 MHz, the maximum rated for the chip.  Typically, the highest usable output frequency from a DDS chip is no greater than about one-third the clock rate, or about 16.6 MHz.

Thus, the KX1 design won't support 18 MHz or higher ham bands because the DDS chip isn't capable of generating cleanly (for a DDS) the required transmit frequency or the high-side receiver local oscillator frequency that is required for one of the sideband reception modes.

The K1, in contrast, doesn't use DDS frequency generation.  Its four-band filter board can be built for 40 and 30 meters, plus ANY TWO of the following three bands:  20m, 17m, 15m.

73,
Mike / KK5F

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[wd4lst-2]

Thanks Mike,
(as well as Paul and Tom),
I just finished studying the KX1 schematic and AD9834 data sheet. You are right on. Analog devices also has an interesting DDS primer at
http://www.analog.com/library/analogDialogue/archives/39-08/dds_apps.html
if anyone is interested.
As an aside, I have been a reader of the Elecraft group for a few months now, as well as some other radio specific groups. This is by far the most informative group that I have read. I have learned alot from the morning read.
thanks to all. I think it is half the draw towards Elecraft.
Now....KX1 or K1....
73's,
Pete wd4lst

>
> From: Mike Morrow <[hidden email]>
> Date: 2006/04/05 Wed PM 05:15:12 CDT
> To: [hidden email],  [hidden email]
> Subject: Re: [Elecraft] KX1 on 17 meters?
>
> >I was wondering if anyone has considered a 17 meter option.
>
> The clocking rate of the KX1's AD9834 DDS chip is 50 MHz, the maximum rated for the chip.  Typically, the highest usable output frequency from a DDS chip is no greater than about one-third the clock rate, or about 16.6 MHz.
>

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[John Young-10]

[hidden email] wrote:
> Now....KX1 or K1....
> 73's,
> Pete wd4lst
>  

Both works for me
John WA8KNE

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