[Elecraft] Another question about L34 adjustment IF Amp.

[Tom Hammond]

Hi Gary:

There's a tuning point, just below the point on L34 where you DO 
achieve max. received signal, where the background noise will drop 
off faster than the received signal. It's (if I recall) about 1/2 to 
1 full turn DOWN from the point of max RX sig.

If you have Spectrogram installed, you can actually see it on the 
spectral display... it's NOT a terribly dramatic effect, but it is 
observable... you WILL lose a bit of received signal strength, BUT 
it's more than compensated for by the fact that the signal-to-noise 
ratio has been improved, so to signal seems to 'stand out' a bit 
better, even though it may be a couple dB lower in level.

73,

Tom Hammond    N0SS


At 10:33 06/28/2007, Gary D Krause wrote:
>After reading another post about adjusting L34 for the IF amplifier, 
>I have another question.  I've wondered about this since completing 
>my K2.  The manual was a bit confusing and from what I can remember, 
>it said to adjust L34 for the strongest signal and lowest background 
>noise.  It also said that a DMM could be used across the speaker 
>output to get a more accurate reading.  Well, my question at the 
>time was how can you get the strongest signal and lowest background 
>noise with only one adjustment.  So, I figured it would be a 
>compromise between the two.  I adjusted L34 but, not exactly to it's 
>highest volume or loudest signal.
>
>Now I've learned that it should be adjusted for the loudest signal 
>and that includes the background noise.  So, can I now go back and 
>readjust L34 for maximum volume and if so what else will I have to 
>align?  I assume that I would only have to re-calibrate the 
>bar-graph, is that correct?
>
>Thanks,
>Gary, N7HTS
>
>
>
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