[R-390] Image problem solved - Not.

[Mark Huss]

Now that is a handy tip.

Jay Rusgrove wrote:
> A 2nd order product (2*F1) drops 2 dB for each 1dB drop of the input signal and a 3rd order
> product(2*F1-F2  and 2*F2-F1) drops 3 dB for each 1 dB drop of the input signal. A step attenuator
> in series with the antenna will help answer the question as to whether the problem is in the
> receiver or external to it. While listening to the undesired signal click in say 6 dB of
> attenuation. If the undesired signal drops by ~12 dB it's a 2nd order product. If it drops by ~18 dB
> it's a third order product. If the undesired signal drops by 6 dB it isn't a 'phantom' signal being
> generated by the receiver, however, it could still result from poor image rejection. Running the
> known frequency and oscillators numbers will show whether or not it could be an image.  It's a good
> idea to click in an a few dB before running the test and leave it in to help 'flatten' the match
> between antenna and receiver.
>
> Jay W1VD
>   


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Some people are like a Slinky .. not really good for anything,
but you still can’t help but smile when you shove them down the stairs.
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