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

Re: re: NO-45 carrier every 20 seconds



So, correcting my own post...  The standard Baycom modem is
wired in a non-standard manner, so this won't work without a
little trickery with the connectors.  But, it is easily done.

Greg  KO6TH


>From: "Greg D." <ko6th_greg@hotmail.com>
>To: mas@wustl.edu, amsat-bb@AMSAT.Org
>Subject: Re: [amsat-bb] re: NO-45 carrier every 20 seconds
>Date: Wed, 22 Oct 2003 21:44:51 -0700
>
>Hi Mike,
>
>The 3105 chip does Bell 202; if that's what you need, then anybody
>with a PC and the old Baycom TNC should be able to send the tones
>you need (I, for one).  If that's all, let me know.
>
>Greg  KO6TH
>
>
>
>>From: Michael Swartwout <mas@wustl.edu>
>>To: amsat-bb@AMSAT.Org
>>Subject: Re: [amsat-bb] re: NO-45 carrier every 20 seconds
>>Date: Wed, 22 Oct 2003 14:37:32 -0500
>>
>>John Mock wrote:
>> > Yes, i can confirm this.  I have heard NO-45 transmitting a pair of
>> > bursts of apparently unmodulated carrier (consistent with length of
>> > an AX25 UI packet) every N seconds each time i've listened in the
>> > several weeks.
>> >
>> > -- KD6PAG
>>
>>That is Sapphire (NO-45)'s beacon; yes, it's just the carrier wave
>>bursting on/off (the two pulses, as timed, are '00' according to our bit
>>definitions).  That indicates that Sapphire is still working -- and has
>>been the only thing we've heard for the past 16 months.  Sapphire has
>>not responded to any connect attempts.  But with some help, we may be
>>able to change that.
>>
>>We believe ('hope' is closer to the truth) that the problem is a
>>software bit flip in the TNC.  (We have the same Kantronics model as
>>PCSAT, without the luxury of two TNCs and without much power cycling to
>>clear the memory.)  If so, then a hard reset of the TNC should clear the
>>problem (the TNC code is stored in radiation-hardened chips).  If it's a
>>hardware problem, then we're stuck with those bursts.
>>
>>We can force an external reset, but as is all-too-common with a student
>>project, the parts necessary to send the reset signal were long since
>>co-opted for other projects and the documentation is somewhat spotty.  
>>Sigh.
>>
>>I do know this much:  the reset works by sending an ASCII text file
>>(converted to 1200 baud AFSK tones, not AX.25 packet).  I tested the
>>reset many times in the mid-90s using PCPlus to upload the file and a
>>TCM3105 chip under Win 3.1.  However, if you try to use this stuff on a
>>newer (32-bit) Windows system, it crashes the terminal program.
>>
>>I'm writing all of this to make an offer:  if anyone out there has any
>>easy way to generate the AFSK tones (like an old Bell-212) and access to
>>an older Windows system (anything with 16-bit DOS), we might be able to
>>recover Sapphire.  Sapphire doesn't do all that much (most importantly,
>>he doesn't have any repeater capabilities), but there are a few toys (a
>>digital camera).  Bob Bruninga may want to share some time (especially
>>trying to tweak Sapphire into an APRS digipeater), but for the most
>>part, the original spacecraft users don't have much use for it.
>>
>>So if someone's got the time, interest and the right tools, let me know.
>>  Maybe we can put the vehicle to good use.
>>
>>-Mike Swartwout
>>Sapphire operations lead (if you can call Sapphire 'operational')
>>
>>--
>>----------------------------------------------------------------
>>Michael A. Swartwout			mas@me.wustl.edu
>>Assistant Professor 			work: 314/935-6077
>>Mechanical & Aerospace Engineering	fax:  314/935-4014
>>Washington University in St. Louis
>>----
>>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
>
>_________________________________________________________________
>Want to check if your PC is virus-infected?  Get a FREE computer virus scan 
>online from McAfee.    
>http://clinic.mcafee.com/clinic/ibuy/campaign.asp?cid=3963
>
>----
>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

_________________________________________________________________
See when your friends are online with MSN Messenger 6.0. Download it now 
FREE! http://msnmessenger-download.com

----
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