Elecraft

RE: PS for K1 or K2

Classic

List

Threaded

3 messages Options

Nigel-14

RE: PS for K1 or K2

I can provide a little information as I recently bought one for use with my
K2 on a forth coming trip to Seattle USA.

The unit is made by XP at www.xpiq.com The specific model is not on their
site but the reference below looks similar.
http://www.xpiq.com/orderPriceList2.php?seriesid=100065&groupid=11&catuid=1&
lang=US&gri=2

I have used it to drive my K2/100 with a KAT100 by connecting it to the K2
12v supply point and then turning off the main supply so the rig then ran
as a low power rig. On receive, the voltage is 13.7 at the K2 input.
Under transmit at 10wts the K2 meter shows a 0.4v drop at a 2.6A load
sending CW v's or holding down the dit or dash paddle. I'm hopeful it
will do the same in the USA when supplied with 110v 60hz (Here in NZ its
230v and 50hz).

Of more importance is the RFI generated. I've used it with my main
antenna, an elevated multi band vertical fed with coax but sitting only 4m
away from the rig and power supply, and with a portable antenna built for
the trip being a 44ft doublet fed with 14m of 300 ohm TV ribbon. The
feedline ribbon was connected directly to the K2 (changed back to a K2 with
KAT2 installed) or via a Elecraft 4:1 balun all in the open sitting directly
under the doublet above.

(Incidentally, with the direct connection, I got swrs after tuning of less
than 1.2:1 on all bands from 40m to 10m except on 40m 5:1 and 12m 3.1.
With the 4:1 balun all swrs were 1.3:1 or less except 40m being 1.6:1 and
10m at 1.4:1. So that looks promising)

The power supply is quite quiet for general radiated hash except on
multiples of its switching frequency of about 60Khz. Away from the
switching harmonics I could not detect power supply noise on either antennas
160 through 10m. The noise injection appear to be via the power lead and
not direct radiation.

On the multiples of the 60Khz up through the band it takes out a 3Khz
section of the band. On 40m, the noise at peak is 20db over s9 but by 15m
it has dropped to about S5 so there is probably output filtering which is
becoming more effective as the frequency goes up. As it warms up the
switching frequency rises but eventually stabilises.

The 60Khz switching frequency is quite high and advantageous as you only get
interference every 60Khz where as my SEC1223 operates at about 20Khz so,
until it was quietened, there were three times as many interference
harmonics in the same bandspace. It would be interesting to know what the
switching frequency of the similar MFJ power supply was.

I figure I will be losing one 3Khz segment every 60Khz up the bands and will
just have to work around them. Hopefully that segment will not include
the ECN frequency or I will need plan B (a battery ;-))

Hope this helps,

73, Nigel ZL2DF

> Message: 31
> Date: Fri, 16 Jun 2006 14:31:56 -0400
> From: "Jim and Carol" <[hidden email]>
> Subject: [Elecraft] PS for K1 or K2
> To: <[hidden email]>
> Message-ID: <000a01c69173$261c1900$01fea8c0@yourf78bf48ce2>
> Content-Type: text/plain; charset="iso-8859-1"
>
> Has anyone had any experience with using OHR's CUP36-12-1
> Power supply for the K1 or K2? Is it acceptable to use. tnx, Jim/k2hn
>

Jim and Carol

Re: RE: PS for K1 or K2

Thanks Nigel and all who responded. Still can't seem to come up with a
quiet ps, at least a small one. Looks like the big (35A etc.) Astrons are
in favor.
Jim/k2hn
----- Original Message -----
From: "Nigel" <[hidden email]>
To: <[hidden email]>
Sent: Saturday, June 17, 2006 9:37 PM
Subject: [Elecraft] RE: PS for K1 or K2

I can provide a little information as I recently bought one for use with my
K2 on a forth coming trip to Seattle USA.

The unit is made by XP at www.xpiq.com The specific model is not on their
site but the reference below looks similar.
http://www.xpiq.com/orderPriceList2.php?seriesid=100065&groupid=11&catuid=1&
lang=US&gri=2

I have used it to drive my K2/100 with a KAT100 by connecting it to the K2
12v supply point and then turning off the main supply so the rig then ran
as a low power rig. On receive, the voltage is 13.7 at the K2 input.
Under transmit at 10wts the K2 meter shows a 0.4v drop at a 2.6A load
sending CW v's or holding down the dit or dash paddle. I'm hopeful it
will do the same in the USA when supplied with 110v 60hz (Here in NZ its
230v and 50hz).

Of more importance is the RFI generated. I've used it with my main
antenna, an elevated multi band vertical fed with coax but sitting only 4m
away from the rig and power supply, and with a portable antenna built for
the trip being a 44ft doublet fed with 14m of 300 ohm TV ribbon. The
feedline ribbon was connected directly to the K2 (changed back to a K2 with
KAT2 installed) or via a Elecraft 4:1 balun all in the open sitting directly
under the doublet above.

(Incidentally, with the direct connection, I got swrs after tuning of less
than 1.2:1 on all bands from 40m to 10m except on 40m 5:1 and 12m 3.1.
With the 4:1 balun all swrs were 1.3:1 or less except 40m being 1.6:1 and
10m at 1.4:1. So that looks promising)

The power supply is quite quiet for general radiated hash except on
multiples of its switching frequency of about 60Khz. Away from the
switching harmonics I could not detect power supply noise on either antennas
160 through 10m. The noise injection appear to be via the power lead and
not direct radiation.

On the multiples of the 60Khz up through the band it takes out a 3Khz
section of the band. On 40m, the noise at peak is 20db over s9 but by 15m
it has dropped to about S5 so there is probably output filtering which is
becoming more effective as the frequency goes up. As it warms up the
switching frequency rises but eventually stabilises.

The 60Khz switching frequency is quite high and advantageous as you only get
interference every 60Khz where as my SEC1223 operates at about 20Khz so,
until it was quietened, there were three times as many interference
harmonics in the same bandspace. It would be interesting to know what the
switching frequency of the similar MFJ power supply was.

I figure I will be losing one 3Khz segment every 60Khz up the bands and will
just have to work around them. Hopefully that segment will not include
the ECN frequency or I will need plan B (a battery ;-))

Hope this helps,

73, Nigel ZL2DF

_______________________________________________
Elecraft mailing list
Post to: [hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft

Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com

_______________________________________________
Elecraft mailing list
Post to: [hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft

Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com

Able2fly

Re: RE: PS for K1 or K2

In reply to this post by Nigel-14

In a message dated 6/17/2006 10:34:28 P.M. Eastern Daylight Time,
[hidden email] writes:

Looks like the big (35A etc.) Astrons are
in favor.

In lieu of a small switching P/S I am using the somewhat heavy but dead
quiet Astron RS-7A that is as quiet as a battery on my K2. I picked up one on
the auction site for $15 recently.

Bill K3UJ
_______________________________________________
Elecraft mailing list
Post to: [hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft

Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com