[GreenKeys] Model 19 progress and a few questions...

[Ralph Mowery]

> -----Original Message-----
> From: greenkeys-bounces at mailman.qth.net [mailto:greenkeys-
> bounces at mailman.qth.net] On Behalf Of E.
> Sent: Monday, August 07, 2017 1:45 AM
> To: WA5CAB--- via GreenKeys
> Subject: Re: [GreenKeys] Model 19 progress and a few questions...
> 
> 
> Hi all!
> 
> Sorry for that last schematic… I was trying to decipher one of the
> previous emails with it, so the circle I had on there was incorrect ;o
> (sorry again).  Since this is still a bit new to me (slowly figuring it
> out), a few more questions:…
> 
> *Does "running open" means being all noisy - clicking away and not
> doing anything except the motor running (as opposed to an open circuit,
> like what was being talked about with the line jack)?
> 
> *If the above does mean running open, that is my case - it’s not doing
> anything with the keyboard.  I have current running though the main
> unit & keyboard (minus the perforator side - for the time being) but
> nothing going on the typing unit (just clicking away noisily).  I got
> lost about the jumping… either with jumping the line jack or the
> terminals on the side (sorry - multiple emails with multiple subjects
> ;p ).  What jumping do I need to do and where, so that it may not run
> open (I’m hoping terminals on the side - the line jack checks out fine
> with the ohm meter)?
> 
> *Will the signal lamp glow when on keyboard?  If it does, looks like I
> have more sniffing out to do...
> 
> Today was mainly a day of taking off the typing unit, checking
> lines/resistors, oiling and trying to figure out the mechanical side of
> it.  May do a video tomorrow… the printing bail blade doesn’t seem to
> be working like it should, but one thing at a time ;o .  After over a
> week of working ’n trying to fix, I’m a bit burnt out tonight, so will
> take a break for the rest of the evening ;p ~…..
> 
> 

Running open means that the current loop going to the selector magnets on the printer is open.  When this happens, the printer will be doing all kinds of mechanical operations and making lots of noise.  When the machine is running closed, then just the motor and the shaft it is connected to is moving and the machine is relative quiet.

The light on the model  19 near the keyboard is set to light up after about 60 some characters have been punched out on the tape punch.  It is to let you know when to put a line feed and mainly a carriage return on the tape as you can not see the amount of characters on the tape.  When you type in a CR the counter will go back to zero and the light will go out.


The wiring in a printer is somewhat difficult.  However all you really need to know is that the magnets on the printer you have seem to be the holding type as it has a switch for series and parallel.  The two coils are in parallel with each other when you use a 60 ma loop current.  They do have to be phased correctly.  If not they will not have much pull.  You will have to reverse the wires going to one coil if this is the case.   The keyboard has a wire gong to the contacts that are all in series with each other. And make and break as the shaft rotates around.   You should be able to pull the two phone type plugs out, hook them in series with a 60 ma loop supply (magnets in parallel with each other) and get the printer to print from the keyboard.  The polarity of the current does not make any difference.

I am not sure what you are using for a loop supply.  The normal type would be about 150 to 200 volts DC with around 2000 ohms of resistance adjusted for the 60 ma loop current.  You can use lower voltage, but  stay above 50 volts to get good results.  

Good luck.