[Elecraft] KPA500/KAT500/W2 order advice needed

[Don Wilhelm]

Jeff,

I am not sure why you want to locate the W2 directional coupler between 
the K3 and the KPA500, but that is your choice.
As far as the high power coupler, what you wish to monitor will dictate 
where you place the coupler.  If you place it between the KAT500 and the 
antenna, you would monitor the unmatched antenna shack end feedpoint 
with its raw SWR.  If you place it between the KPA500 and the KAT500, 
you would monitor the matching condition into the KAT500, which should 
indicate a low SWR.

The KAT500 SWR LEDs indicate the matching condition at the input of the 
KAT500
The KAT500 Utility can indicate the BYPASS SWR which is the unmatched 
SWR of the antenna feedline, so you can obtain the same information 
there as placing a coupler after the KAT500 - of course, you would need 
an extra serial port if you wanted to operate with the KAT500 Utility 
open on your computer.

73,
Don W3FPR

On 12/28/2014 11:45 PM, Jeff Hall, W6UX wrote:
> Hi everyone,
>
> I presently have a K3/100 hooked up to a P3 and a Microkeyer II.  I want to add three new Elecraft products to my lineup: KPA500 amp, KAT500 tuner, and the W2 watt meter.
>
> There are many options listed on the Elecraft ordering page and I'm not sure if I have all the necessary cabling options selected.  Additionally I need advice on which directional couplers I should choose for the W2.
>
> Here are the items currently in my shopping cart:
>
> - KAT500-K (High Power ATU, Kit)
> - E850463 (KAT500 to KPA Aux Cable)
> - KPA500-K (500W Linear Amplifier, Kit)
> - KPAK3AUX (KPA to K3 AUX Cable)
> - CBL36UHF (36" Coax cable) (three: K3->W2, W2->KPA500, KPA500->KAT500)
> - PWR-US240a (US 240V Power Cord) -- extra, for future use when I have a 240v line
> - W2-K (W2 Wattmeter, Kit)
> - DHCF-200 (0.1-200W 1.8-54MHz directional coupler)
> - DHCF-2000a (1-2000w 1.8-53MHz directional coupler)
>
> So, have I forgotten anything critical to get everything connected?  The Microkeyer II uses the RS-232 port on the P3 and the ACC port on the K3.  The KPAK3AUX cable Kit includes a Y-cable for the ACC port so that should make room for the Microkeyer II to be inserted into the rest of the K-Line gear.
>
> I picked the 0.1-200W directional coupler as I wanted to put the W2 between the K3 and the KPA500.  Is it worthwhile adding the second coupler for 1-2000w? I'm assuming you only use this if you want to place the W2 after the KAT500?
>
>