Forgot the link to Array Solutions
RF Limiter / Front Load Protector (Helps to know what they call these
items so you can search for them :-) i.e.. "Front End Protector".
http://arraysolutions.com/Products/as_rxfep.htm
That's a terrible protection system. It would deteriorate almost any
receiver, unless you are using a super regenerative.
Back-to-back diodes by themselves are a poor enough system. They generate
significant intermod with a sum of all signals at .5 volts RMS, which is a
sum of signal power (from all signals) of only 7 dBm at 50 ohms or 5.2 dBm
into 75 ohms. Back-to-back diodes even deteriorate performance below that
threshold with most small fast signal diodes, some fast small signal diodes
start to create unwanted mixing products at 0 dBm or less.
Back-to-back diodes driven by minicircuits type transformers would be worse
yet. I can't use minicircuits transformers on my Beverages here, because of
IMD.
A properly designed clamp would have no effect up to about 20-23 dBm, where
it would clamp hard, and would not include easily-saturated very small core
transformers.
Be careful with anything that uses back-to-back diodes.
73 Tom
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Topband reflector - topband@contesting.com
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