[Elecraft] KAT500 power question

[Wes (N7WS)]

Jack,

Thanks for your remarks.

I will be using AUX Bus interconnects, however, the KPA500 has yet to be 
assembled and frankly the Elecraft cables are too spendy so they are coming from 
elsewhere.

I don't use a P3 (an SDR-IQ is my preference) so the 12V spigot is available. 
However, using that port to power a relay is going in the wrong direction for 
me. I'd like to reduce the mess of cables and needing one more from the desktop 
to the supply underneath was what I wanted to avoid. I've just had to add a 
Rigrunner to power more devices in my "wireless" station.

'Tis a pity that the KAT500 can't treat the bus like the KRC-2 and KPA500.

Wes N7WS


On 10/4/2014 7:20 PM, Jack Brindle wrote:
> Godo questions. The power sequencing key is that the KAT500 must be powered before the K3 initializes the Auxbus. You actually have a little bit of time after the K3 powers on before this happens, and the KAT500 powers up quickly to wait for this activity, so if you were able to power the KAT500 from the K3’s power jack, it will work just fine. I do this in my own station by powering a relay from the K3. The relay then switches power to the remaining peripherals, including my KAT500, K3  and  KRC2. I can’t answer the question as to whether the upgraded K3 can directly power a KAT500 - my own has not been upgraded and with the power setup I have I don’t need it.
>
> As for the KRC2, we have not seen any problem of this sort so far (and it has been a long time…). The KRC2’s Auxbus circuitry is slightly different from the KAT500, which seems to allow it. Before anyone asks, the KPA500 does not have this problem at all. It only transmits on the Auxbus, and the isolation driver transistor it uses very effectively prevents any problem.
>
> As for the interconnect, I highly recommend using the Auxbus connection, especially if a KPA500 is in use. When properly configured, the three devices work very well together to provide an excellent user experience. To borrow a phrase, they just work.
>
> 73!
>
> Jack B, W6FB
>
>