[1000mp] Mark V Push to Talk RF Spike

[Jim W7RY]

Is it an audio noise spike or an ALC spike?  Perhaps you have DC on your 
microphone input line causing a POP when you key the microphone? Does 
the  PTT switch break the microphone line? You did not say what kind of a 
microphone it was... Have you tried different mic? Does it have the 
issue?  Is the noise electrical or mechanical?

Things to ponder.
73
Jim W7RY


I know that some At 04:23 PM 4/14/2005, you wrote:
>Mike:
>
>         You don't mention what kind of mic, or the circuit,
>so I have to guess here, but it sounds like the PTT switch
>is completing an audio circuit (in addition to grounding
>the PTT line). If so, the PTT switch make cause a coupling
>Capacitor in the microphone or mic input circuit to suddenly
>become connected, and thus generate a huge spike while it
>charges up.
>
>         Using VOX, you might not close the PTT switch, so no
>coupling transient in the audio input would take place.
>
>         Don't know if this is right, but it would mimic your
>symptoms exactly.
>
>         -- Tom, N5EG
>
>
>
>
> > Hello Yaesu Fans:
> >
> > I have found that when operating PTT, that my Mark V
> > spikes RF each time I key the microphone.  It does this
> > with each microphone I have tried.  It appears that
> > the spike is caused by noise input to the microphone
> > preamp as the microphone cartridge is always in the
> > circuit, so as to be able to be used for VOX operation.
> >  With the microphone gain turned full CCW, there is no
> > spike during PTT.
> >
> > I normally use VOX, so this is not always an issue,
> > but I would like to find a possible solution to the
> > problem.  The spike is greatly amplified by my linear,
> > and needs to be eliminated.
> >
> > Has anyone experienced this issue?
> >
> > Thanks for your input.
> >
> > 73 and Happy DXing,
> >
> > Mike Schatzberg
> > WB2AJI
>
>______________________________________________________________
>1000mp mailing list
>Home: http://mailman.qth.net/mailman/listinfo/1000mp
>Help: http://mailman.qth.net/mmfaq.html
>Post: mailto:1000mp at mailman.qth.net