At 10 kHz the attenuation is 8 dB, so the stated noise figure of 27 dB at
9 kHz complies with this.
Exactly.
And the qst-quoted MDS of -127dBm @ 2.4kHz (surley somewhere >1MHz )
which means af NF of 13dB is too optimistic by 5dB anyway.
Perseus has around 18dB-20dB NF depending on the input settings and frequency.
I've attached a frequency response curve by IK2ODO.
Hopefully it passes the spam filter of the server.
73
Clemens
DL4RAJ
----- Original Message -----
From: "Roelof Bakker" <[email protected]>
To: <[email protected]>
Sent: Sunday, June 06, 2010 12:21 PM
Subject: Re: LF: Re: Re: VLF 9 kcs: preamp and antenna noise
Dear Jim,
The figures Clemens quotes for the Perseus RX are curious <
PERSEUS has a rf-isolating transformer at the input, which has a low
frequncy roll off.
At 10 kHz the attenuation is 8 dB, so the stated noise figure of 27 dB at
9 kHz complies with this.
Best regards,
Roelof Bakker, pa0rdt
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Perseus frequency response.pdf
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