Hi, Phil, You need one 15-pin ACC cable from K3 to KAT500 and another from KAT500 to KPA500. The KAT500 has two 15-pin connectors, one in and one out. See N6TV's back panel picture at http://www.elecraft.com/KAT500/kat500rear_visalia.jpg the connectors are labeled "Control" (XCVR and AMP).
This arrangement allows the ATU to interrupt the amplifier key line during tuning. It's a serial component to component chain, not a star, from the K3 to the KPA500. The KAT500 wires each pin of the 15-pin connector to the equivalent on the other, except that the amplifier key line goes through a relay. If you use two 15-pin ACC cables, you do not also need an RCA connection for "PTT RLY" or amplifier key line. The amplifier keying line is duplicated within the 15-pin cable. For amplifier key line interrupt, you should use two 15-pin cables, or two RCA cables (radio to ATU, ATU to amplifier). But you can't use one of each. The RCA connectors and 15-pin ACC cables use different poles of a double pole amplifier key line interrupt relay. The ATU and amplifier both count transmit frequency, and both will operate without this 15-pin connection. The minimal connection for any radio (including K3) and any amplifier (including KPA500) is a two-wire cable with RCA plugs from radio to ATU and another from ATU to amplifier. When the KAT500 and KPA500 have band information (in the ACC cable), they can band switch without transmission, which turns out to be very convienent, particularly if band switch implies an antenna switch. The ATU returns to the last-used settings on the new band and your receiver works better than it might if the ATU were still tuned for the old band. You won't need a Y unless you have other users of the ACC connector at the K3 end. Some of us use the Y at the back of the K3 for FSK, PR-6, antenna switch band decoders and the like. You might eventually find a second Y useful if your needs at the back of the K3 expand. That ACC connector has a lot of uses. We don't currently show an order item for the 15-pin two meter cable separate from the Y and the little amplifier key line interrupter that form the KPAK3AUX kit. The cable required is the same. While I don't know the exact cost breakdown of the components, I would expect that the price for a cable-only "kit" wouldn't be a whole lot lower than the KPAK3AUX kit. The 15-pin cable in the KPAK3AUX supply is two meters long. That's a lot of relatively stiff cable to find a place for when the amp and ATU are one atop the other (either way), although some find it goes down the wall OK. You might find a shorter cable (perhaps 6 to 12 inches) more to your liking. Phil, AD5X, used 10-conductor shielded cable and DB15HD connectors for his KPA500 to MFJ ATU connection. See his KPA500 review article. which includes parts sources and part numbers. http://www.ad5x.com/images/Presentations/KPA500%20Review.pdf The K3 owner's manual shows the 15-pin ACC connector pinout. The KAT500/KPA500 combination uses (at most) BAND0-BAND3, AUXBUS, Ground, PTT/KEY, ALC, and Amp inhibit. That's 9 wires, and you can use the shield between the shells. 73 de Dick, K6KR -----Original Message----- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Phil Hystad Sent: Saturday, October 06, 2012 8:42 AM To: Phil Hystad Cc: elecraft@mailman.qth.net List; Eric Swartz WA6HHQ - Elecraft Subject: Re: [Elecraft] KAT500 Gang, Thanks to all who took the time to answer my question below. I now understand the need and the configuration. Just to be sure I will repeat below: When running the K3+KPA500+KAT500 together, to achieve the band following/switching features of the KAT500 you need an extra cable from the K3. Thus, 1. Y-adapter placed on the back of the K3. 2. One KPAK3AUX cable running from K3 (Y-adapter) to the KPA500. 3. One KPAK3AUX cable running from K3 (Y-adapter) to KAT500. I just checked the web site (Order page) and found that there is no KPAK3AUX cable listed as part of the KAT500 section. Of course there is with the KPA500 but I thought that one came with a Y-adapter as well as the cable. Question: is there a KPAK3AUX cable by itself available from Elecraft or do you need to buy the kit again that included the Y-adapter. Seems to me it would be cheaper if you could exclude the Y-adapter and that other little thing they include. PEH On Oct 5, 2012, at 9:42 PM, Phil Hystad <phys...@mac.com> wrote: > Eric, > > I have not been keeping up here but can you clarify what you are saying below. Here, let me ask: is this "additional" cable needed to use the KAT500 with a KPA500 and K3 for all normal operating. I already placed my order for the KAT500 and I am wondering if I ordered enough stuff. I have the K3+P3+KPA500. > > 73, phil, K7PEH > > > On Oct 5, 2012, at 9:26 PM, Eric Swartz WA6HHQ - Elecraft <e...@elecraft.com> wrote: > >> You will need to purchase an additional KPAK3AUX cable if you wish to send band data in advance of TX from the K3 to the KAT500. >> >> 73, >> >> Eric >> >> www.elecraft.com >> _..._ >> >> >> >> On Oct 5, 2012, at 12:23 PM, Jim Sheldon <w...@cox.net> wrote: >> >>> I guess the question now becomes - Is that cable going to be supplied with the KAT500 or do I have to contact Elecraft and have an additional cable placed on the order I put in back in May, during the Dayton Hamvention? Been waiting patiently for that order to be filled so it would be nice to know if I have to order another cable before the KAT500 finally gets here. >>> >>> Jim Sheldon - w0EB >>> >>>> For a K-line, you'll want a 15-pin cable from K3 (after the Y) to >>>> the KAT500 and another from the KAT500 to the KPA500. The KAT500 >>>> interrupts the KPA500 key line in that cable during tune, and both >>>> the KAT500 and KPA500 observe the K3's BAND0 thru BAND3 lines. >>>> >>>> If you aren't using a K3, then the KAT500, like the KPA500, can >>>> sense band changes by counting the Tx frequency. >>>> >>>> But it's very convenient to band switch the K3 and have the ATU and >>>> amp follow without requiring a transmission. The ATU switches to >>>> the last-used antenna on band switch (or to a fixed antenna you >>>> configure). It's nice not to have to send a "dit" to make that >>>> antenna switch happen. >>>> >>>> The manual is in progress. >>>> >>>> 73 de Dick, K6KR >>>> >>>> >>>> -----Original Message----- >>>> From: elecraft-boun...@mailman.qth.net >>>> [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of DGB >>>> Sent: Friday, October 05, 2012 11:54 AM >>>> To: elecraft@mailman.qth.net >>>> Subject: Re: [Elecraft] KAT500 >>>> >>>> I have currently have a y-cable at the rig for the MH MKII and the >>>> KPA-500. >>>> How will the KAT-500 play into that? A Y-Cable on the KPA-500? >>>> I see no manual for the KAT-500 yet! >>>> >>>> 73 Dwight NS9I >>>> ______________________________________________________________ >>>> Elecraft mailing list >>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft >>>> Help: http://mailman.qth.net/mmfaq.htm >>>> Post: mailto:Elecraft@mailman.qth.net >>>> >>>> This list hosted by: http://www.qsl.net Please help support this >>>> email list: http://www.qsl.net/donate.html >>>> >>>> ______________________________________________________________ >>>> Elecraft mailing list >>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft >>>> Help: http://mailman.qth.net/mmfaq.htm >>>> Post: mailto:Elecraft@mailman.qth.net >>>> >>>> This list hosted by: http://www.qsl.net Please help support this >>>> email list: http://www.qsl.net/donate.html >>> ______________________________________________________________ >>> Elecraft mailing list >>> Home: http://mailman.qth.net/mailman/listinfo/elecraft >>> Help: http://mailman.qth.net/mmfaq.htm >>> Post: mailto:Elecraft@mailman.qth.net >>> >>> This list hosted by: http://www.qsl.net Please help support this >>> email list: http://www.qsl.net/donate.html >> ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:Elecraft@mailman.qth.net >> >> This list hosted by: http://www.qsl.net Please help support this >> email list: http://www.qsl.net/donate.html > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net Please help support this email > list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
