[GreenKeys] Model 33 Progress

[Brad]

I’ve been reading (or trying to) the technical manual from Sep 1975.  It’s quite detailed although very long and in some cases not as specific as I’d like.

 

I did some poking around before and mostly it all seemed to be correct, although the filter cap for the (send/receive?) magnet is gone.  There’s a pretty ugly looking GE cap also that I haven’t figured out how to probe while in operation because it’s behind the PCB with all the resistors.  But I think I will go ahead and get rid of most of these just to eliminate that issue.  I really can’t see anything mechanical causing these issues – obviously the mechanical side is capable of working.. there’s just something preventing it from working consistently.

 

From: drlegendre . [mailto:drlegendre at gmail.com] 
Sent: Monday, November 7, 2016 6:53 PM
To: Brad <unclefalter at yahoo.ca>
Cc: GREENKEYS BULLETIN BOARD <GreenKeys at mailman.qth.net>
Subject: Re: [GreenKeys] Model 33 Progress

 

Brad,

Which documents are you working from? There are a number of 33 docs floating around, and you might benefit from a larger selection. 

And yes, there are a number of caps associated with the TU and KB. Have you spec'd out the PSU at all? Measured voltages, compared against spec, etc?

Again, I don't have any 33-specific exp. but from listening on this list, it's clear that they have a much more complex (and failure-prone) PSU than the earlier models. For example. the M15 KSR is pretty much all electro-mech - I believe the whole system is AC, and if there are any caps, they're on the motor**. 

If it were my 33, I'd probably freshen up the PSU (new caps..) as a matter-of-course, just to keep that crap out of my hair.

(**This is for basic 117V AC mains units, that don't require one of the boat-anchor PSUs down inside the table).

 

On Mon, Nov 7, 2016 at 8:28 PM, Brad via GreenKeys <greenkeys at mailman.qth.net <mailto:greenkeys at mailman.qth.net> > wrote:

Sorry for asking this – I do have the manual in PDF but because it’s so large it causes my reader to delay 5-10 seconds each time I ‘turn’ a page.  Definitely want to order printed copies I think!

 

Question – is there a capacitor involved in any way with the typing unit/keyboard?  It feels to me like we have something where not enough power is being consistently delivered.  If I press a letter key and hold repeat long enough, eventually the printhead will start moving and typing (wrong) characters.  And the punch also starts punching out different codes, where before it was only punching the fourth hole in from the right, if at all.

 

I’ve done my best to clean the contacts and associated pins/wires, but that hasn’t made a significant difference, although Line Feed is now working if I hit it enough times.

 

Going to try to (painfully) flip my way through the PDF here and see if I can understand more about how it works.


______________________________________________________________
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> 

2002-to-present greenkeys archive: http://mailman.qth.net/pipermail/greenkeys/ <http://mailman.qth.net/pipermail/greenkeys/1998-to-2001> 
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 drlegendre at gmail.com <mailto:drlegendre at gmail.com> 

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/greenkeys/attachments/20161107/614244fa/attachment-0001.html>