[Yaesu] Re: [1000mp] Hum on phonepatch input-FT-1000MP

[Richard (Rick) Karlquist (N6RK)]

Sometimes the transformer can pick up 60 Hz
fields from a nearby power transformer.  Moving
it away will fix that.

Rick N6RK

> -----Original Message-----
> From: yaesu-bounces at mailman.qth.net
> [mailto:yaesu-bounces at mailman.qth.net]On Behalf Of Ronald Walters
> Sent: Monday, November 22, 2004 6:00 PM
> To: Jim W7RY; All about Yaesu 1000mp; Yaseu Users Group; Ft1000MP Users
> Subject: [Yaesu] Re: [1000mp] Hum on phonepatch input-FT-1000MP
>
>
> Thanks Jim, I have the same setup but without the 470 ohm resistor across
> the input to the patch plug.  Will give that a try, thanks again
>
> Ron - W4LDE
>
> ----- Original Message -----
> From: "Jim W7RY" <w7ry at centurytel.net>
> To: "Ronald Walters" <rwalters8 at cfl.rr.com>; "All about Yaesu 1000mp"
> <1000mp at mailman.qth.net>; "Yaseu Users Group" <yaesu at mailman.qth.net>;
> "Ft1000MP Users" <1000mp at qth.net>; "Ft1000MP" <1000mp at mailman.qth.net>
> Sent: Monday, November 22, 2004 20:56
> Subject: Re: [1000mp] Hum on phonepatch input-FT-1000MP
>
>
> > I just hooked mine up for a contest voice recorder to use with
> my Writelog
> > contest logging recorder.
> >
> > Here is what I ended up with.
> >
> > 100 ohm resistor across the output of the sound card. Then 10K ohm
> resistor
> > in each leg. Then a Radio Shack 1:1 transformer. Then a 470 ohm resistor
> > accross the output of the transformer and onto the phone patch input of
> the
> > radio. Built it on a piece of Radio Shack perf board.
> >
> > No hum. I do have a little RF getting into things when I run 1500 watts.
> > Have not trouble shot it yet though.
> >
> >
> > I hope you can decipher that.
> >
> > 73
> > Jim W7RY
> >
> >
> > At 05:14 PM 11/22/2004, Ronald Walters wrote:
> > >The soundcard software program that I occasional run needs USB,
> > >it is MT63 by IZ8BLY, unfortunately my old MP does not have the CPU
> upgrade
> > >that allows for the packet mode USB but only LSB.
> > >
> > >For the record I use the packet input for all other soundcard modes and
> they
> > >work great without any hum, however if I use the phone patch
> input on the
> > >back of the MP I can hear some hum.  I am using isolation transformers
> for
> > >all inputs to and from the MP to the computer.
> > >
> > >Question?  Does anyone know if there is a load requirement for
> the phone
> > >patch input.
> > >
> > >I am using a Radio Shack 1:1 isolation transformers, any suggestions?
> > >Should I isolate the transformer with a cap?  Any parallel resistor
> network
> > >required?
> > >
> > >Ron W4LDE
> > >
> > >
> > >_______________________________________________
> > >1000mp mailing list
> > >1000mp at mailman.qth.net
> > >http://mailman.qth.net/mailman/listinfo/1000mp
> >
>
>
> _______________________________________________
> Yaesu mailing list
> Yaesu at mailman.qth.net
> http://mailman.qth.net/mailman/listinfo/yaesu
>
>