Confusion is clearing a bit, check my thinking on this.................. The
400hz filters are listening over a portion of the band away from the section
where the mark and space tones will be heard. So the reason it sounds so
beautifully quiet is because I'm listening to the null outside the filters
bandpass. Yes?
The TS-450 has a +/-2.2Khz IF shift. This may not be quite enough to get the
RTTY signal inside the passband. The 450 also has a menu option to change the
receiver tone from 2125 to 1275hz. This may be irrelevant though as it is for
FSK mode.
I'll be back in the op chair this afternoon and give these options a try then
get back to the email thread. PLAN-B if this fails, is there a simple &
inexpensive interface that I can use to do true FSK. USB to 13pin
DIN...........??
David
> Date: Sat, 25 Sep 2010 23:00:31 -0400
> From: lists@subich.com
> To: rtty@contesting.com
> Subject: Re: [RTTY] INRAD filter question
>
>
> > Okay, so you think if I adjust my IF shift it will help?
>
> If the IF shift has enough range it will work. Find a "dead"
> place on the band, select the narrow filers and turn the IF
> shift one way or the other to the stops and see if you hear
> noise come up.
>
> 73,
>
> ... Joe, W4TV
>
> On 9/25/2010 10:39 PM, David VE3VID wrote:
> >
> > Okay, so you think if I adjust my IF shift it will help?
> >
> >
> >
> > When I click either filter in its like a dead band as I tune along. Like a
> > 60db attenuator is on.
> >
> >
> >
> >
> >
> >
> >
> >
> >> From: w7ry@inbox.com
> >> To: ve3vid@hotmail.com; rtty@contesting.com
> >> Subject: Re: [RTTY] INRAD filter question
> >> Date: Sat, 25 Sep 2010 19:14:30 -0700
> >>
> >> you can probably use the BPF and IF shift to center LSB into the filters
> >> passband. Then you will have to use 2125/2295 for tones.
> >>
> >> 73
> >> Jim w7RY
> >>
> >>
> >> --------------------------------------------------
> >> From: "David VE3VID"<ve3vid@hotmail.com>
> >> Sent: Saturday, September 25, 2010 7:06 PM
> >> To: "RTTY contest group"<rtty@contesting.com>
> >> Subject: Re: [RTTY] INRAD filter question
> >>
> >>>
> >>>
> >>> The laptop is a Gateway running XP, N1MM, into a SignaLink USB outboard
> >>> sound card, into the ACC port on the TS-450s. I am neither for or
> >>> against true FSK, just the SignaLink allows me to do many other types of
> >>> "sound card" digital modes such as PSK and Olivia.
> >>>
> >>>
> >>>
> >>> I was able to do RTTY no problem with the system before the 400hz filters
> >>>
> >>>
> >>>
> >>>
> >>>
> >>>> From: w7ry@inbox.com
> >>>> To: ve3vid@hotmail.com; rtty@contesting.com
> >>>> Date: Sat, 25 Sep 2010 18:52:16 -0700
> >>>> Subject: Re: [RTTY] INRAD filter question
> >>>>
> >>>> FSK is MUCH better than AFSK.... What are you using for a computer and
> >>>> software? I use windows XP and MMTTY with N1MM. Works just fine in FSK
> >>>> mode.
> >>>>
> >>>> Is there a particular reason you don't want to run FSK?
> >>>>
> >>>> 73
> >>>> Jim W7RY
> >>>>
> >>>>
> >>>> --------------------------------------------------
> >>>> From: "David VE3VID"<ve3vid@hotmail.com>
> >>>> Sent: Saturday, September 25, 2010 6:48 PM
> >>>> To: "RTTY contest group"<rtty@contesting.com>
> >>>> Subject: Re: [RTTY] INRAD filter question
> >>>>
> >>>>>
> >>>>> Wow. Well if thats the case it was an expensive waste of $300.
> >>>>>
> >>>>> However, why would the filters be unusable in AFSK(LSB)? Dont they just
> >>>>> narrow the IF bandpass to 400hz?
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>>>> From: w7why@frontier.com
> >>>>>> To: rtty@contesting.com
> >>>>>> Date: Sat, 25 Sep 2010 18:43:48 -0700
> >>>>>> Subject: Re: [RTTY] INRAD filter question
> >>>>>>
> >>>>>> Hi David
> >>>>>>
> >>>>>> I have the same setup as you--2 Inrad filters. They won't work in
> >>>>>> AFSK.
> >>>>>> You have to run FSK to use the narrow CW filters. 73
> >>>>>> Tom W7WHY
> >>>>>>
> >>>>>>
> >>>>>>>
> >>>>>>> Ummmm.......nope. I had the rig in LSB (AFSK). And the tone pair as
> >>>>>>> set
> >>>>>>> by MMTTY is 2125/170
> >>>>>>>
> >>>>>>>
> >>>>>>>
> >>>>>>
> >>>>>> _______________________________________________
> >>>>>> RTTY mailing list
> >>>>>> RTTY@contesting.com
> >>>>>> http://lists.contesting.com/mailman/listinfo/rtty
> >>>>>
> >>>>> _______________________________________________
> >>>>> RTTY mailing list
> >>>>> RTTY@contesting.com
> >>>>> http://lists.contesting.com/mailman/listinfo/rtty
> >>>>>
> >>>>
> >>>>
> >>>>
> >>>>>
> >>>>> No virus found in this incoming message.
> >>>>> Checked by AVG - www.avg.com
> >>>>> Version: 9.0.856 / Virus Database: 271.1.1/3159 - Release Date:
> >>>>> 09/25/10
> >>>>> 10:45:00
> >>>>>
> >>>> _______________________________________________
> >>>> RTTY mailing list
> >>>> RTTY@contesting.com
> >>>> http://lists.contesting.com/mailman/listinfo/rtty
> >>>
> >>> _______________________________________________
> >>> RTTY mailing list
> >>> RTTY@contesting.com
> >>> http://lists.contesting.com/mailman/listinfo/rtty
> >>>
> >>
> >>
> >>
> >>>
> >>> No virus found in this incoming message.
> >>> Checked by AVG - www.avg.com
> >>> Version: 9.0.856 / Virus Database: 271.1.1/3159 - Release Date: 09/25/10
> >>> 10:45:00
> >>>
> >
> > _______________________________________________
> > RTTY mailing list
> > RTTY@contesting.com
> > http://lists.contesting.com/mailman/listinfo/rtty
> >
> _______________________________________________
> RTTY mailing list
> RTTY@contesting.com
> http://lists.contesting.com/mailman/listinfo/rtty
_______________________________________________
RTTY mailing list
RTTY@contesting.com
http://lists.contesting.com/mailman/listinfo/rtty
|