[GreenKeys] 404 OPM Speed for TT-4/TG

[Duncan Brown]

Dale,

I realized after I sent the email that the motor governor might not have 
sufficient range, but it was worth a try!

I will look and see what I have in the way of 50 baud gears on Tuesday.

73 & have fun

Duncan
K2OEQ

On 3/8/2026 5:49 PM, Dale Hughes via GreenKeys wrote:
> Hi Duncan,
>
> Hello from Canberra, Australia!
>
> I would also be interested in a set of the 50 baud gears if they're 
> available. I also have a TT4C machine which only has 45.5 and 75 baud 
> gears. I have tried to adjust the motor speed to change the machine 
> speed up to 50 baud from 45 baud but I found the governor didn't have 
> enough range. Attached is a photo of my setup.
>
> 73
> Dale Hughes VK1DSH
>
>
> On Mon, 9 Mar 2026 at 04:14, Duncan Brown <duncanancy at earthlink.net> 
> wrote:
>
>     Pete,
>
>     I will check our stock at the AWA (Antique Wireless Association -
>     not to  be confused with Amalgamated Wireless Australia) Museum
>     when I am there on Tuesday.  I know I have extra gears, but don't
>     know offhand if there are any 404 opm gears.
>
>     All mechanical TTY machines can receive over a +/- 10% speed
>     variation, using the Range Control to adjust when the selector
>     magnet reads the data.  So your TT-4 can copy 66wpm with the 368
>     opm gears (just turn the Range control down to about 20), but of
>     course you will need the 404 opm gears to transmit 66 wpm.
>
>     You could also try increasing the motor speed by about 10% while
>     still using the 368 opm gears.  I don't know how increased speed
>     would affect the life of the motor or brushes.  But since the unit
>     was designed to work 24/7, and as long as you only use it a few
>     hours a day, I wouldn't think it would affect its life significantly.
>
>     Good luck & have fun,
>
>     Duncan Brown, K2OEQ
>     USASA    31J30
>
>     Antique Wireless Association
>      Communication Technologies Museum
>        Asst. Curator, Commercial Equipment
>     (also chief TTY op & repairman)
>
>     i-Telex: 212503
>
>     www.antiquewireless.org <http://www.antiquewireless.org>
>
>     AWA Youtube channel:
>     https://www.youtube.com/channel/UCX55peBhzeX1qps_VYXdLBA
>
>     Virtual AWA Museum TTY Tour:
>     https://www.youtube.com/watch?v=TpB6jM90VV8
>
>
>
>     On 3/8/2026 6:17 AM, Peter Leonard wrote:
>>     Hello all,
>>
>>     I need a gearset for a TT-4/TG to operate at 404 OPM / 66WPM / 50
>>     baud. I am happy to exchange a 368.1 OPM / 60 WPM / 45.45 baud
>>     set and a 600 OPM / 100 WPM set. The TT-4 manual states that the
>>     368.1 OPM set is normally fitted and the 404 OPM set is held
>>     inside the machine. My machine is fitted with a 368.1 OPM set
>>     holds a 600 OPM set.
>>     I am located in Adelaide Australia and am happy to pay parcel
>>     post both ways.
>>
>>     Kind regards,
>>
>>     73 Pete   VK5XP
>>
>>
>>     Peter Leonard
>>
>>
>>     ______________________________________________________________
>>     GreenKeys mailing list
>>     Home:http://mailman.qth.net/mailman/listinfo/greenkeys
>>     Help:http://mailman.qth.net/mmfaq.htm
>>     Post:mailto:GreenKeys at mailman.qth.net <mailto:GreenKeys at mailman.qth.net>
>>
>>>>>     Jordan Spencer Cunningham's GreenKeys Search Tool:https://teletype.net/gksearch
>>>>>     2002-to-present greenkeys archive:http://mailman.qth.net/pipermail/greenkeys/
>>>>>     1998-to-2001 greenkeys archive:http://mailman.qth.net/archive/greenkeys/greenkeys.html
>>>>>     Randy Guttery's 2001-to-2009 GreenKeys Search Tool:http://comcents.com/tty/greenkeyssearch.html
>>     This list hosted by:http://www.qsl.net
>>     Please help support this email list:http://www.qsl.net/donate.html
>>     Message delivered toduncanancy at earthlink.net
>
>     ______________________________________________________________
>     GreenKeys mailing list
>     Home: http://mailman.qth.net/mailman/listinfo/greenkeys
>     Help: http://mailman.qth.net/mmfaq.htm
>     Post: mailto:GreenKeys at mailman.qth.net
>
>     >>> Jordan Spencer Cunningham's GreenKeys Search Tool:
>     https://teletype.net/gksearch
>     >>> 2002-to-present greenkeys archive:
>     http://mailman.qth.net/pipermail/greenkeys/
>     >>> 1998-to-2001 greenkeys archive:
>     http://mailman.qth.net/archive/greenkeys/greenkeys.html
>     >>> Randy Guttery's 2001-to-2009 GreenKeys Search Tool:
>     http://comcents.com/tty/greenkeyssearch.html
>
>     This list hosted by: http://www.qsl.net
>     Please help support this email list: http://www.qsl.net/donate.html
>     Message delivered to dalevk1dsh at gmail.com
>
>
> ______________________________________________________________
> GreenKeys mailing list
> Home:http://mailman.qth.net/mailman/listinfo/greenkeys
> Help:http://mailman.qth.net/mmfaq.htm
> Post:mailto:GreenKeys at mailman.qth.net
>
>>>> Jordan Spencer Cunningham's GreenKeys Search Tool:https://teletype.net/gksearch
>>>> 2002-to-present greenkeys archive:http://mailman.qth.net/pipermail/greenkeys/
>>>> 1998-to-2001 greenkeys archive:http://mailman.qth.net/archive/greenkeys/greenkeys.html
>>>> Randy Guttery's 2001-to-2009 GreenKeys Search Tool:http://comcents.com/tty/greenkeyssearch.html
> This list hosted by:http://www.qsl.net
> Please help support this email list:http://www.qsl.net/donate.html
> Message delivered toduncanancy at earthlink.net
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/greenkeys/attachments/20260308/5ffd4b19/attachment.html>