[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

Re: 38k4 Modem Considerations



Is Echo running 12 KHz deviation? There is little advantage running a
modulation index of less than one.
Art, KC6UQH
----- Original Message -----
From: "Colin Hurst" <cjhurst@bigpond.net.au>
To: "amsat-bb@AMSAT. Org" <amsat-bb@AMSAT.Org>
Sent: Thursday, July 15, 2004 4:58 PM
Subject: [amsat-bb] 38k4 Modem Considerations


> Recent mails on the -bb have touched on 38k4 downlink requirements, hence
> some words of advice.
> When considering equipment for 38k4 ensure that the RS232 communications
> capability from TNC to Computer is at least twice that of the downlink,
viz:
> for 38k4 this is 76k8 or higher.
> Pressing an old computer or TNC into service when either has a com port of
> 38k4 maximum speed, may result in "overflow" errors.
> Those with a spare 9k6 G3RUH Modem may consider modifying it to 38k4 using
> the information contained in the following link
> http://www.amsat.org/amsat/articles/g3ruh/109a.txt
> This article also identifies the receiver bandwidth required for 38k4 as
60
> kHz.
> Modification to most amateur transceivers is required to achieve this
> bandwidth.
>
> Colin VK5HI.
> ----
> Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
> Not an AMSAT member? Join now to support the amateur satellite program!
> To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org
----
Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
Not an AMSAT member? Join now to support the amateur satellite program!
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org



AMSAT Top AMSAT Home