[Johnson] 250-39 TR switch.

[Peter Markavage]

Back issues of Electric Radio Magazine are still available from Electric
Radio.
http://www.ermag.com/index.cfm 

Pete, wa2cwa

On Fri, 24 Oct 2008 11:48:30 -0400 "Carl" <km1h at jeremy.mv.com> writes:
> OK, thanks.
> 
> Now does anyone have a copy of that April 1993 article they will 
> share?
> 
> Carl
> KM1H
> 
> 
> ----- Original Message ----- 
> From: "Peter Markavage" <manualman at juno.com>
> To: <Johnson at mailman.qth.net>
> Sent: Friday, October 24, 2008 11:04 AM
> Subject: Re: [Johnson] 250-39 TR switch.
> 
> 
> > There is a simple online Electric Radio Index. Covers all the 
> issues 
> > from
> > day 1 and continues to be updated every month.
> > http://home.wi.rr.com/n9oo/ersearch.html
> >
> > With a few simple key strokes, Dennis's article pops out in the 
> list.
> >
> > Pete, wa2cwa
> >
> > On Fri, 24 Oct 2008 10:38:51 -0400 "Carl" <km1h at jeremy.mv.com> 
> writes:
> >> Do you remember which ER issue?
> >>
> >> Carl
> >> KM1H
> >>
> >>
> >> ----- Original Message ----- 
> >> From: "Dennis" <radioart at charter.net>
> >> To: <kb2wig at twcny.rr.com>; "Roy Morgan" <k1lky at earthlink.net>
> >> Cc: <Johnson at mailman.qth.net>
> >> Sent: Friday, October 24, 2008 8:16 AM
> >> Subject: Re: [Johnson] 250-39 TR switch.
> >>
> >>
> >> > Another point of view on these TR switches....
> >> >
> >> > I have three of them in use and they work great.  As long as 
> you
> >> keep
> >> > the connection between your transmitter and the TR switch 
> short
> >> the
> >> > suckout mentioned will be slight; its because of this issue 
> that
> >> > Johnson put an RF amp in the TR switch so signals won't be
> >> degraded.
> >> > You will notice some changing of signal levels when you change 
> the
> >>
> >> > loading on your transmitter; but thats normal.  In my case I 
> have
> >> my
> >> > CE 100V & 600L coupled with a NC-303 using a Johnson TR switch 
> and
> >> I
> >> > have two Johnson Desk KW's using the Johnson TR switch and they 
> do
> >> a
> >> > great job.  Into a 50 ohm load they will provide you over 4kw 
> of
> >> > switching protection to your receiver.....  Not too bad...
> >> >
> >> > With regard to the TVI, not an issue any more with cable and
> >> satilite
> >> > but in the good old days Johnson recommenced using a Low Pass
> >> filter
> >> > with the TR switch;  In those days most shacks already had a 
> LP
> >> filter
> >> > in the antenna line, I know I did, is it wasn't ever an 
> issue....
> >> >
> >> > I remember I wrote an article for ER (Electric Radio)  
> magizine
> >> > discussing the many different TR switchs and their pros and 
> cons.
> >>
> >> > Maybe you can get a copy....
> >> >
> >> > Ciao, Dennis, k0eoo
> > Johnson mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/johnson
> > Help: http://mailman.qth.net/mmfaq.html
> > Post: mailto:Johnson at mailman.qth.net
> > 
> 
> 
>