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Old January 24th 14, 03:58 PM posted to rec.radio.amateur.antenna
Ralph Mowery Ralph Mowery is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 702
Default Relationship Between Antenna Efficiency and Received Signal Strength


"Jerry Stuckle" wrote in message
...
And yes, many inexpensive "modern" receivers suffer from poor front

ends. And since transistors (especially bipolar) typically generate more
noise than tubes,
noise can be a worse problem now than in the 60's. You can get low noise
transistors, but these are more expensive.

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How did ou come up with transistors generate more noise than tubes ?

Most of my research into low noise has been above 50 mhz and the beter tubes
generate much more noise than transistors. The older U310 devices have a
noise figure less than 2 db at 150 mhz and a 6cw4 will have around 3 db.
Cheap gaasfets have noise figuers less than 1 db.

I seem to remember that most tube sets of the old days were stating about .5
uv senstivity on ssb, and many of todays ham trasceivers are way less than
that.



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