Re: 9600 baud packet instability
- 1.0x10-5 (or better) is good benchmark to look for on the RX BER at 50 dBm test and the TX "BER at 12-dB SINAD+30 dB" test. If a radio can't perform well at those levels then good luck with it on the 9.6k airwaves.
A really good article by KE3Z in the May 1995 QST goes into BER testing details and what makes a good 9600 baud radio (or not). Unfortunately I don't think it's openly available on the internet.
I might check to see if the ARRL would allow me to PDF it and post it publicly if there is enough interest.
"Packet Radio never died, it just evolved."
--- In BPQ32@yahoogroups.com, Bill Vodall <wa7nwp@...> wrote:
> > (DR-235 BER data per ARRL Lab results)
> > Receiver:
> > BER at 12-dB SINAD, 3.8×103
> > BER at 16 dB SINAD, 1.4×104
> > BER at 50 dBm, 2.4×105
> > transmitter:
> > BER at 12-dB SINAD + 30 dB, 3.4×104
> What numbers would a good radio have? 1x10-6?
- Thank you Jeff.. That's good info to keep on had.
> 1.0x10-5 (or better) is good benchmark to look for on the RX BER at –50
> dBm test and the TX "BER at 12-dB SINAD+30 dB" test. If a radio can't
> perform well at those levels then good luck with it on the 9.6k airwaves.
- That was with a Kantronics KPC-9612 and on a Timewave DSP-232USB.Rick/n9umj
Sent from my iPhone
On Nov 16, 2012, at 11:31 AM, Bill Vodall <wa7nwp@...> wrote:
> I agree totally, I've had the Dr235t in operation for a year and found its
> performance on 9.6k nominal and unreliable as a backbone,
> During heavy use the dr235t will distort the packets to the points they
> cannot be decoded even at short distances.
Is that with the built in 9k6 TNC or a "good" external TNC like the PK96?
Bill - WA7NWP