[GreenKeys] 5A stock ticker

[W2HX]

I agree, they don't get much respect. Six bit is correct, speed on mine
seems to be 67 baud, although there were other speeds according to the
manual.  Also the code wasn't 100% standard ITA5. Some of the bit patterns
produce the fractions.

73 Eugene W2HX


-----Original Message-----
From: greenkeys-bounces at mailman.qth.net
[mailto:greenkeys-bounces at mailman.qth.net] On Behalf Of John Nagle
Sent: Saturday, July 25, 2009 12:31 PM
To: greenkeys at mailman.qth.net
Subject: Re: [GreenKeys] 5A stock ticker

W2HX wrote:
>> PS. I also have two 5A black boxes, one was a donor for the other. Jack
>> K0TTY got one of them working a few years ago. I have yet to find the
time
>> to reproduce his set up! 

     Those things get no respect, because they're so blah-looking.

     They're not really "tickers"; they're Teletype printers that
take a special six-bit code.  The electrical input is polar; the
line reversed polarity rather than simply being on-off, but it's
ordinary 6-bit start-stop async.  See

    http://www.prc68.com/I/WU5A.shtml#5APC

who found that 80VDC through 750 ohms at 50 baud would work.

They were probably set up for polar operation because previous
ticker networks were set up for polar operation, and they could
thus change out the machines without rewiring the transmission
system.

					John Nagle
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