AFSK not only can provide a nice splatter generator (as Gary noted some
folks will tell you), but it also can be susceptible to RF on the incoming
AF transmit audio lines, depending on how you decouple it (or not.) I've
always found FSK to be far easier to set up, and far harder to screw up.
So, for me and some other folk, it's just easier so that's why we use it.
Unfortunately, that connection scheme won't help with PSK31 or other modes
that don't work well with the RTTY tones.
73, Duane
Duane Calvin, AC5AA
Austin, Texas
www.ac5aa.com
-----Original Message-----
From: tentec-bounces@contesting.com [mailto:tentec-bounces@contesting.com]
On Behalf Of Gary Hoffman
Sent: Monday, January 26, 2009 9:32 PM
To: Discussion of Ten-Tec Equipment
Subject: Re: [TenTec] Omni VI Mod 3 and RTTY
People will tell you that AFSK can be set up badly, so as to splatter and
make a mess. That's true.
But then again - so can FSK.
I'd do AFSK cause its so much easier....but take the time to learn how to do
it right and make sure to do so.
73 de Gary AA2IZ
----- Original Message -----
From: "Bob McGraw - K4TAX" <RMcGraw@Blomand.net>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Monday, January 26, 2009 10:26 PM
Subject: Re: [TenTec] Omni VI Mod 3 and RTTY
In my opinion {there's a dangerous word} FSK is for the die hard purist.
AFSK is much easier, specially with today's radios, computers, software and
interface boxes.
73
Bob, K4TAX
----- Original Message -----
From: "Tim Randa" <tranda@cox.net>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Monday, January 26, 2009 9:20 PM
Subject: Re: [TenTec] Omni VI Mod 3 and RTTY
A quick question on the subject. Why bother with the FSK when AFSK gets
the job done with much less hassle. Is there an advantage to FSK that I
as a extremely casual RTTY user haven't a clue about?
de Tim KØFL
Bob McGraw - K4TAX wrote:
> I too used my Omni VI Plus on FSK. The 250 Hz filter worked will with the
> PBT properly adjusted. The manual covers the alignment of the PBT
> circuit.
>
> One extremely important point in using FSK is that the BFO oscillators
> need
> to be very precisely aligned. Follow the steps in the manual in their
> exact
> order. You probably will find it necessary to do this 2 or 3 times as
> there
> is some interaction with the adjustments. Also, a frequency counter that
> can read something in the order of 9 MHz to a resolution of 0.1 Hz is of
> great help and almost a necessity. For better results, be sure the radio
> is
> operating at room temperature for at least 1/2 hr with the covers in place
> before making these adjustments.
>
> After doing all of this, I too found AFSK was much easier to use. Took
> the
> audio IN and OUT from the connectors on the back panel and I let the VOX
> handle the RX/TX switching.
>
> 73
> Bob, K4TAX
>
>
> ----- Original Message -----
> From: "Ed" <w3nr@comcast.net>
> To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
> Sent: Monday, January 26, 2009 3:15 PM
> Subject: Re: [TenTec] Omni VI Mod 3 and RTTY
>
>
>
>> Jerry Pyle wrote:
>>
>>> I am in the process of setting up my station to run RTTY, preferably
>>> FSK.
>>>
>>> My Omni VI Mod3 has all of the filter slots filled and upon inspection I
>>> found that there is not a 217 filter amongst the bunch.
>>>
>>> I have been on the searchable archives looking for a possible Inrad
>>> filter
>>> that will work in place of the 217 (which we all know TenTec no longer
>>> makes) or another workable solution using my existing 500hz filters.
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>> Jerry - WB7S
>>>
>>> Basin, WY
>>>
>>>
>>>
>>> http://wb7s.home.bresnan.net
>>>
>>>
>>>
>>> 73
>>>
>> I use my Omni6 on RTTY without a problem. Had a 217 and sold it, too
>> narrow. Use LSB and your 500hz filter(s) and you won't have a problem.
>>
>> FSK is fine as long as the 2 xtals are 170Hz apart, any more/less you
>> will not be happy. I use AFSK and as long as it is set right you won't
>> have any problems.
>>
>> If you do use FSK, the PBT needs to be set at 3 o'clock.
>>
>> All that is needed for the FSK keying cicuit is a 1K resistor in series
>> with the TXD line.
>>
>> Ed W3NR
>> _______________________________________________
>> TenTec mailing list
>> TenTec@contesting.com
>> http://lists.contesting.com/mailman/listinfo/tentec
>>
>>
>
>
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
> ------------------------------------------------------------------------
>
>
> No virus found in this incoming message.
> Checked by AVG - http://www.avg.com
> Version: 8.0.176 / Virus Database: 270.10.13/1916 - Release Date:
> 1/26/2009 7:08 AM
>
>
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
|