[GreenKeys] TT-4C start-up progress

Sat Jul 14 22:48:08 EDT 2012

Thanks again Steve, no I did not supply the loop current, I had it in my mind that it had something to do with the printing part.  

I have been given a low power 240 to 120 V transformer but that is AC and I have been told that rectifying that output will actually result in a higher potential than 120 V because that is RMS voltage and that I really need about 90 V AC to get proper 120 V DC...I'll take my friend's word for it, and we'll get something sorted.  I was trying to cut and paste a figure from the manual (can't seem to do it) but going on the diagram I speak of the terminal configuration is the same as what you are describing when the machine is a "receiving" terminal...as if the original loop current was coming from the sending machine.  It makes sense to me!

Looking forward to getting this up and running.

regards,

Greg.

________________________________
 From: Steve Garrison <steve.n4tty at gmail.com>
To: 'Greg Arnoldussen' <gregga73 at yahoo.com.au>; greenkeys at mailman.qth.net 
Sent: Sunday, 15 July 2012 2:05 AM
Subject: RE: [GreenKeys] TT-4C start-up progress

Greg,

Do you have a 120v DC power source connected to the TT-4 to energize the selector magnets?

On the line terminal board, with the shorting bars in place across terminals 2&3 and across 5&6, you would have the DC supply connected at  terminals 1&4.  With the LINE switch in the DC LINE position, the LINE INCREASE variable resistor should be adjusted to show 60ma on the meter.

It takes a DC loop supply for the motor stop relay circuitry to work properly.  Manually closing the motor stop contact (S6) should cause the motor to come on and the machine to run open.  Running open would explain the "tat, tat, tat" noise you describe.

The BREAK key only comes into play if the DC loop supply is present and the motor stops because the machine has received a MOTOR STOP signal, which is nothing more than receiving the letter "H" while the machine is shifted into the FIGURES mode.  You should be able to manually latch the motor stop relay armature into the latched position and it should remain there until the next MOTOR STOP signal is received.

I guess the main point I'm trying to make is that you are going to need a DC loop supply before things will appear to be working normally.

As for paper, I don't have a ready source, but if you were here in the States I could a couple rolls to you in short order, but not sure what we would need to do to get those same rolls to you down under.  We just recently had a place in New York unload a bunch of roll paper that fits perfectly in my TT-4 and I picked up a case of 12 rolls from the guy that purchased the whole lot.  Anyone headed Greg's way on vacation?

Get hold of a 120V DC loop supply and you should be in business.

Steve G./N4TTY

From:greenkeys-bounces at mailman.qth.net [mailto:greenkeys-bounces at mailman.qth.net] On Behalf Of Greg Arnoldussen
Sent: Friday, July 13, 2012 11:13 PM
To: greenkeys at mailman.qth.net
Subject: [GreenKeys] TT-4C start-up progress

I spent most of my nights this week cleaning the first of my two TT-4Cs, serial number AW-176 (with the other being AW-247).  I chose the one with the surface corrosion - a white crystalline deposit which was removed using fine sandpaper, a toothbrush and simple green, taking care not to allow any of the debris to fall into the mechanism, where possible I wedged in a cloth underneath to help.  I decided it was far better not to take apart this machine to the point where I could have trouble getting it back together again (even by following the manual).  I still have more cleaning to do.  The removal of the paper guard on the rear really helped with accessibility.  

This machine is already well greased but I oiled the felts and turned the motor by hand and all of the components respond without complaint.  The fuses seemed OK.

I purchased a 240 to 115V transformer and plugged in the machine, the earth strap is designed to connect to a wire which ends up connected to a post in the ground (for Army field use) but as the best earth I could use is the earth pin of the socket itself I have used that.  It is not pretty but it does the job for now and I will have to purchase modern proper US style plugs (retaining the original plugs of course).

I switched on the unit with no effect.  I tried the break switch with no luck.  I tried striking some keys and no good.  I put the cover back on to see if the light worked and yes it did, so that told me power was getting in.  Nonetheless, I still could not get the motor to work.  I replaced a fuse without luck.  I removed the TT from the base and turned it carefully onto its side to remove the electronic circuit cover at the rear.  It is amazingly clean as if it was made yesterday.  Nothing looked leaky and cables were not loose.

Last night my electrical engineering friend (a very cluey guy)came around and after an hour or so worked out the relay beside the bell on the right hand rear corner of the machine was open, its normal state is closed.  When we closed the relay and started the motor everything fired with a steady "tat, tat, tat" noise.  This is good!  We tried to understand why the relay was open.  The only way to close it was by hand, and we figured that either (a) the machine had been decommissioned and this was a safety step or (b) a remote TT had opened the relay and only a remote TT can open it again.  Personally I thought the BREAK switch should engage the motor as stated in the manual, but it did not work when I tried, perhaps someone might know?  I struck a few keys but nothing typed, maybe this has something to do with the armature setting or jumper settings. Despite reading both op and service manuals it is still a whole new world to me and I have to
 remind myself I am dealing with fifty year old technology!   

I do not want to run this machine too much yet before I am confident everything is working internally with grease and oil.  So I am now going to go over the lubrication schedule next and to synchronise the motor with the tuning fork (I am have trouble with this, I think the procedure requires a fairly fine turn of the screw).  All in all a very successful week.

PS.  Where do you guys source rolls of  paper from?  I got some strange looks from the office supply shop.  Fax paper is not the right paper I told them. 

cheers,

Greg in Wangaratta.
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