[Elecraft] RTTY Filters 180Hz off QRG

[Dominik Bugmann]

Don et all

My issue was solved behind the scenes. Gary gave the right hint. My 4MHz
quarz (X2 on Control Board) was 170Hz off frequency. I realigned and
everything is back to normal. By coincidence the 170Hz added more confusion
because it is also the shift in RTTY.

I don't know why my 4MHz run away 170Hz. Either I touched C22 while
installig KDSP2, or X2 gets old or C22 vibrated away while tranported in my
car (10 contests and 50km one way).

BTW: my K2 uses RTTY ("r") mode and FL2, 3, and 4 cover 2125/2295 Hz window.
15m and above I was able to shift the center frequency that high. Bands
below 15m require RTTY reverse (press CW RV button) and "reverse" the signal
in the RTTY decoder (in my case MMTTY). This setup worked fine for 1000 RTTY
Contest QSOs.

I do not run any low tones (they are supported by MMTTY) because the 1st
harmonic would go through the passband of FIL OP1. Furthermore, I run SO2R
(SingleOp2Radio) and I don't know whether my brain can cope with a high
tones TRX (Omni VI+) and a low tone TRX (e.g. K2).

cu in WAEDC RTTY.

73 de Dominik, HB9CZF

----- Original Message -----
From: "Don Wilhelm" <w3fpr@peoplepc.com>
To: "Dominik Bugmann" <hb9czf@swiss-artg.ch>; <elecraft@mailman.qth.net>
Sent: Thursday, October 23, 2003 2:29 AM
Subject: Re: [Elecraft] RTTY Filters 180Hz off QRG


> Dominik,
>
> I did not see another answer on the reflector to your question and thought
I
> might help.
>
> The problem is that your BFOs for FL2, FL3 and FL4 are not the same as
they
> are for FL1.
> Why would that make a difference you may want to ask -- look at the
> instructions for the SSB option, and you will find that the K2 ALWAYS
> transmits (in SSB or RTTY modes) using the BFO settings for FL1.
>
> Simply set the BFO to the same frequency setting for all 4 filters - but
> also be certain that the audio tones you are using are contained within
the
> passband.  The soundcard generated digital modes can handle altered tones
> with no problem - just tell the program what tones to use, but a hardware
> TNC may not have the capability to modify the tones used.
>
> Also, if you prefer to use the SSB filters as they are now for SSB
> operation, then enable "RTTY" mode which gives you an additional set of 4
> filters to use for the digital modes.  The documentation for the version
2.x
> firmware provides the information on enabling RTTY mode.
>
> 73,
> Don W3FPR
>
> ----- Original Message -----
> |
> | I'm lost with my K2 since CQWW RTTY. At the start of the contest I could
> not
> | work anybody until I figured out that my K2 shifts the RX QRG by 180 Hz.
> | During the Contest I solved the issue with RIT but I want to figure out
> what
> | happened.
> |
> | Right now I have an Omni VI+ on one side and the K2 on the other. Omni
is
> | using the built in FSK.
> | K2 is using AFSK(high tones) through a DIGI-1 interface connected to the
> PC.
> |
> | K2 is on 21050kHz, and "FL1 OP1" selected. I can tx and rx between both
> TRX.
> | No issues at all.
> | If I select "FL2 1.00" the RTTY tones jump by 180Hz. The same for FL3
and
> | FL4.
> |
> | Any idea how this can happen ? (Firmware is 2.03d 1.07)
> |
> | I double-checked in USB, LSB and CW mode and everything is ok. CW is
> surely
> | ok because I did 200 QSO last weekend in EU Spring and Oceania Contest.
> | Earlier this year RTTY was transceive as well and I run about 1000
> | RTTY-Contest QSO's.
> | The only change I did was the KAF2 -> KDSP2 replacement (KDSP2 is
bypassed
> | and no change).
> |
> |
>
>
>