Steve,
Couple of questions to rule out gain distribution issues:
1) On the sense antenna input do you have the pre-amp turned on or off?
2) Is your sense antenna intrinsically inefficient like a beverage or
K9AY loop or is it something efficient like a tribander up reasonably high?
3) Is your sense antenna intrinsically efficient when you include the
feed line loss (I assume the feedline loss on your main TX antenna is
very low)?
73, Mike W4EF............
On 3/14/2020 9:40 AM, n2icarrl@gmail.com wrote:
This discussion of Hi Z amplifiers has been quite interesting.
Excellent information from W1FV and K7TJR.
I have an RX amp question, related but slightly off-topic.
I have an MFJ-1025/1026 noise canceler. I like to use it on the higher
HF bands to cancel power line QRN. The noise is typically S3-S4, but I
want it down to S0 to hear the bottom layer of stations. My sense
antenna works fine, and the QRN is canceled. However, the MFJ-1025
amplifier noise is quite significant, often negating the QRN
cancellation. The MFJ amplifiers are J310's. Any recommendations for
something quieter ?
73,
Steve, N2IC
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