Re: For what is a crystal spotter used?


Bob Parr
 

Thank you for such a through explanation!
 
Bob
KG5GTE

> A crystal spotter is just a simple oscillator which will emit a
> very low level signal when a crystal is attached. It's used to
> locate the crystal's operating frequency in a receiver, when the
> receiver is not slaved to the same oscillator as its companion
> transmitter.
>
> It's very useful with the Bayou Jumper, which has a wide pass band
> regenerative receiver, completely independent of the transmitter.
> If you're calling CQ with a Bayou Jumper you need to know where on
> the receiver dial to look for replies, since most operators using
> modern VFO controlled transceivers will zero beat your signal. It
> also helps to find out if there is other activity on your crystal
> frequency so you won't QRM them.
>
> The spotter does not have to be connected to the receiver, just
> placed nearby. Enough signal leaks out to be easily heard.
>
> BTW - whenever you are the "other op" trying to call and work a
> Bayou Jumper, remember that poor fellow has a regen. It's wide as a
> barn door, very sensitive, but he has to manually throw a switch
> and then perhaps tweak the tuning a bit to get back to where he
> was.  His or her tuning may be as much as a couple kHz or more from
> a dead-on zero beat. So the typical "drop your call once" won't cut
> it.
> Sending  "callsign  callsign   de   mycall  mycall   AR" is makes
> it much easier for that poor schmuck  :^))
> Back in the "spy days" the home station would call the outstation
> for several minutes to allow time for the hard pressed agent to get
> everything tweaked up.
>
> second BTW - because of all this, a Jumper-to-Jumper QSO is a real
> challenge and an accomplishment to be savored.
>
> Jim, N5IB
> 007
> Bayou Jumper almost WAS....   -AK
>
>
>

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