Envelope-to: dave@picks.force9.co.uk Delivery-date: Thu, 02 Feb 2006 12:55:25 +0000 Received: by ptb-mxcore01.plus.net with spam-scanned (PlusNet MXCore v2.00) id 1F4dze-0005wc-LJ for dave@picks.force9.co.uk; Thu, 02 Feb 2006 12:55:25 +0000 Received: from post.thorcom.com ([193.82.116.20]) by ptb-mxcore01.plus.net with esmtp (PlusNet MXCore v2.00) id 1F4dze-0005sh-7t for dave@picks.force9.co.uk; Thu, 02 Feb 2006 12:55:22 +0000 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1F4dz1-0003Vx-5H for rs_out_1@blacksheep.org; Thu, 02 Feb 2006 12:54:43 +0000 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1F4dz0-0003Vo-Md for rsgb_lf_group@blacksheep.org; Thu, 02 Feb 2006 12:54:42 +0000 Received: from sccrmhc12.comcast.net ([204.127.200.82]) by relay1.thorcom.net with esmtp (Exim 4.51) id 1F4fIz-0007Va-70 for rsgb_lf_group@blacksheep.org; Thu, 02 Feb 2006 14:19:40 +0000 Received: from JAYTERMINAL (c-67-177-102-19.hsd1.ct.comcast.net[67.177.102.19]) by comcast.net (sccrmhc12) with SMTP id <20060202125415012007vt4ke>; Thu, 2 Feb 2006 12:54:20 +0000 Message-ID: <003601c627f7$c864ea60$6401a8c0@JAYTERMINAL> From: "Jay Rusgrove" To: rsgb_lf_group@blacksheep.org References: <000701c62720$be51b3a0$6401a8c0@JAYTERMINAL> <1246025403.20060201202249@dx.ru> <1941044238.20060201210259@dx.ru> <486075040.20060202130106@dx.ru> <000901c627ec$a44d91f0$2201a8c0@pcroelof> Date: Thu, 2 Feb 2006 07:54:14 -0500 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1158 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1165 Subject: LF: Re: J310 IMD figures Content-Type: text/html; charset=windows-1252 X-SA-Exim-Scanned: Yes Sender: owner-rsgb_lf_group@blacksheep.org Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group X-SA-Exim-Rcpt-To: rs_out_1@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false X-PN-SpamFiltered: by PlusNet MXCore (v2.00) Content-transfer-encoding: 8bit

Roelof

Had an opportunity to build 6 of the Amrad CP666 e probes (for a military customer) a while back and measured the following. First column is measurments from the QST article, second column is measurment average of the 6 antennas built (all measured within a dB or so of each other), third column Amrad circuit with single J310 at 12 volts and fourth column single J310 at 24 volts.

Measured significantly higher IP2 than the original article leading me to believe there might have been a measurement error in the original article...or I got a batch of CP666s that were unusally good performers. The fact that the J310 at 12 volts achieved +50 dBM makes me lean toward possible measurement error in the original article.

Hope these columns stay lined up when passing through the reflector!

                      Amrad article         W1VD built           J310 12volt       J310 24 volt


1 dB comp.    +25 dBm                +25 dBm            +17 dBm            +18 dBm

IP2                +53 dBm*              +60 dBm             +50 dBm           +60 dBm

IP3                +37 dBm                +36 dBm             +32 dBm          +32 dBm

Gain -16.7 dB -16.5 dB -10 dB -10 dB

* possible measurement error

Jay, W1VD

----- Original Message -----

From: "Roelof Bakker" <roelof@ndb.demon.nl>

To: <rsgb_lf_group@blacksheep.org>

Sent: Thursday, February 02, 2006 6:34 AM

Subject: LF: J310 IMD figures

> Hello all,
>
> Thanks to Andre Kesteloo for forwarding the update on the AMRAD active whip
> design and pleased to see that the CP666 is still available.
>
> Regarding the advice for substuting the CP666 for a J310 and the quoted
> second and third order IMD figures, I have measured these and found IP2 = +
> 65 dBm and IP3 = + 30 dBm. At 12 volt the J310 should be biased for 10 -12
> mA, excellent for battery operation. These figures are in the same league as
> for the CP666 and I am tempted to purchase one and find out if there is any
> difference in practice.
>
> Best regards,
>
> Roelof Bakker, pa0rdt
>
>