[GreenKeys] Western Union tape transmitter 22-A by J H Bunnell

Donald Lampert via GreenKeys greenkeys at mailman.qth.net
Sun Feb 1 14:12:42 EST 2015


Thanks, Duncan for the WU info and photo, as I just got a WU 21-A multiplex tape printer from Lee Mushel. There isn't much online about these units, but I did find the manual for it at the navy-radio site.
It needs the tape holder can from the right side, and most of the wiring and power cord are gone but the mechanics are cleaning up nicely - any idea where to get parts?
Thanks, Don L
--------------------------------------------
On Sun, 2/1/15, Duncan Brown <duncanancy at earthlink.net> wrote:

 Subject: Re: [GreenKeys] Western Union tape transmitter 22-A by J H Bunnell
 To: greenkeys at mailman.qth.net
 Date: Sunday, February 1, 2015, 10:07 AM
 
 Jag,
 
  From around 1910 on, it was customary in high
 volume communication 
 centers (both
 commercial & military) to first punch messages into
 paper 
 tape using the 5-bit Baudot code. It
 would then be read by a tape reader 
 and
 sent out onto the signal line at the maximum system speed. 
 A loop 
 of tape between the tape-punching
 machine (perforator) and the tape 
 reader
 acted as a buffer to accept variations in the typist's
 speed. The 
 tape could be resent to multiple
 destinations and was also kept as a 
 copy of
 what had been sent.  This was the standard for all
 high-volume 
 message traffic in both
 commercial and military communications up until 
 the 1970s.
 
 The
 picture enclosed shows a Western Union Operating table of
 about 
 1920. The perforator is on the right,
 with the tape reader to its left 
 (look
 closely and you can see the loop of tape between the two). 
 The 
 tape reader read the 5 bits in
 parallel, then they were sent to a 
 parallel
 to serial converter (distributor) where they were (time 
 division) multiplexed with up to 3 other
 circuits and sent out 
 (serially) on the
 line. A page printer is on the left.
 
 I am familiar with Bunnell as a manufacturer of
 telegraph equipment, but 
 did not know that
 they made "printing telegraph" equipment. Please
 send 
 a picture of your unit (you can
 enclose a file of up to 1 MB on this 
 email
 list).
 
 Western Union bought
 equipment from a lot of different manufacturers and 
 put their own name & model number on
 them.  But they often used the same 
 model
 number for different types of equipment.  for Example, you
 have a 
 WU Model 22-A tape reader, but there
 was also a WU Model 22A tape 
 printer, so it
 can be confusing.
 
 Have
 fun,
 
 Duncan Brown, K2OEQ
 USASA  31J30
 
 Antique Wireless Association Museum Asst.
 Curator, Commercial Equipment
 (also Chief
 TTY operator & repairman)
 http://www.antiquewireless.org/
 
 
 
 On
 31-Jan-15 17:47, jag wrote:
 >  Hi
 folks.
 >
 > This is my
 first ever post and I was wondering if you could help me...
 
 > I have acquired a tape transmitter but
 know very little about it... 
 > Any
 information would be helpful. Its made by J H Bunnell for
 the 
 > Western Union company. The model
 number is 22-A. I believe its dated 
 >
 around 1920 - 1930. The serial number on the item is 80.
 > What could it have used for? Were they
 widely used in the UK? Armed 
 > forces
 usage? I purchased the item in north Wales as it intrigued
 me 
 > as to its history and use.
 >
 > Thanks in advance.
 >
 > Jag
 >
 
 
 
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