Topband: Preamp for 160

Greg - ZL3IX zl3ix at inet.net.nz
Tue May 20 14:20:55 EDT 2008


Dan Zimmerman N3OX wrote:
>> Will these connector types cause allot of loss to the incoming signal 
>> or do I just solder on the >coax as though they were pl-259's
>
> No measurable loss will occur if you just solder cheap radio shack RCA
> connectors to the coax or use adapters to some more common RF
> connectors. I doubt you'd get measurable loss if you taped the coax
> into the connectors ;-)
>
> Here's a photo I took of a chain of 18 or so adapters, including some
> very cheaply made phono adapters, passing 100W at 1.8MHz with not even
> a watt of noticeable loss:
Hi Dan,

The problem with cheap connectors is not loss, but the type of plating 
they use.  With the wrong type, and a trace of damp, the micron thick 
layers of corrosion can make very good IMD generators.  Not a problem if 
you have no nearby strong signals, but with some MFBC around, you really 
need to watch out.

73, Greg, ZL3IX


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