Author Topic: 1258MKII Audio Codec Quality for Digimodes  (Read 5789 times)

DL9DAK|N9DAK

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1258MKII Audio Codec Quality for Digimodes
« on: 2015-04-28, 19:16:19 »
Hello,

has anyone compare the quality of a audio streaming for digimodes like PSK31 from a remote location vs. a direct connection without 1258MKII's?

I am interesting in knowing more about the codec used in the 1258MKII. Some types of digimodes are very sensitiv for nonlinear distortion and so it can be happend that low level digital signals via an audio compressed link can not be decoded (depending on the codec algorithm) or only with a higher error rate. 

Would be great to here some experiences from HAMs using 1258MKII with PSK and other modes like JT65 etc.

Regards,
Peter
DL9DAK | N9DAK

dj0qn

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Re: 1258MKII Audio Codec Quality for Digimodes
« Reply #1 on: 2015-04-29, 00:42:14 »
My group here in Germany has tested various modes including JT modes with no problem. I can give you more
details if you write me directly (deutsch geht auch in Ordnung).

dj0qn (at) darc.de

73,
Mitch DJ0QN / K7DX

ag7c - Pete

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Re: 1258MKII Audio Codec Quality for Digimodes
« Reply #2 on: 2015-04-30, 18:08:18 »
Hi folks,

I am using RRC-1258 MkII pair with a K3/0-mini and K3/100 primarily on PSK and MFSK modes.

I have found Audio Quality Mode 3  - alaw 12bits 12KHz to be very good for phone use.

I have found Audio Quality Mode 4  - Linear 12bits 12KHz to be noticeably better for digital mode receive with fldigi.

Pete
AG7C 

PA0TCA

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Re: 1258MKII Audio Codec Quality for Digimodes
« Reply #3 on: 2016-06-23, 11:44:36 »
Is there some who tried using wsjt mode JT65A iam not able to use this mode. Everything works up to JT6M

VE3VEE

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Re: 1258MKII Audio Codec Quality for Digimodes
« Reply #4 on: 2016-06-23, 14:22:15 »
I'm not too big on digital modes, but I've done some QSOs (just under 200 dxcc entities) via RemoteRig in the past year or so using RTTY, PSK31, PSK63, JT65 and JT9. I just use Audio Quality 2 - Linear 16 bits 8 kHz. I haven't experimented with better audio quality settings. I use Fldigi and wsjtx.

Marvin VE3VEE

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Re: 1258MKII Audio Codec Quality for Digimodes
« Reply #5 on: 2016-06-24, 11:43:37 »
Hi rtty, psk work fine. But with wsjt i have a problem. The mode's jtms, fsk441,iscat a/band jt6m
work fine on rx/tx. With jt6a  receive is no problem. But my outgoing tx signal is somehow garbled, used
also the higher audio bandwith settings in the 1258's. The tx no alc and reduced pwr .