Dear Jay,
How is the -16dB “gain”
defined?
Cheers, Jim Moritz
73 de M0BMU
-----Original Message-----
From:
[email protected] [mailto:[email protected]] On Behalf Of Jay Rusgrove
Sent: 02 February 2006 12:54
To: [email protected]
Subject: LF: Re: J310 IMD figures
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
