Topics

Dead TM500 plug-in sought


Colin Herbert
 

I am looking for a dead TM500-series module. What I actually want is the frame and rear connector with the aim of bringing out various backplane connections to the front panel. The idea is to be able to check on some voltages and to test the pass transistors easily. I don't want to pay a fortune for a plug-in that wants repairing, I want something which is non-functional. I don't mind paying for shipping, but only within the UK or perhaps Europe.
I live in London, UK, so I don't think shipping from far-flung places will be sensible.
Call it recycling.
TIA, Colin.


Jim Ford
 

Something like this: w140.com/tekwiki/wiki/Dennis_Tillman_7V10 but for the TM50X series mainframes?  Would be handy, Colin.Jim Ford Sent from my Verizon, Samsung Galaxy smartphone

-------- Original message --------From: "Colin Herbert via groups.io" <colingherbert=blueyonder.co.uk@groups.io> Date: 7/24/20 9:56 AM (GMT-08:00) To: TekScopes@groups.io Subject: [TekScopes] Dead TM500 plug-in sought I am looking for a dead TM500-series module. What I actually want is the frame and rear connector with the aim of bringing out various backplane connections to the front panel. The idea is to be able to check on some voltages and to test the pass transistors easily. I don't want to pay a fortune for a plug-in that wants repairing, I want something which is non-functional. I don't mind paying for shipping, but only within the UK or perhaps Europe.I live in London, UK, so I don't think shipping from far-flung places will be sensible.Call it recycling.TIA, Colin.


 

Colin,

I can send you the TM500 frame parts and a rear mating connector PCB free if you can cover the
padded bag shipping cost the the UK. email me off list at:
walter2 -at- sphere.bc.ca

regards,
walter
sphere research corp.


DaveH52
 

I bought one of these to act as an extender:
https://www.amazon.com/gp/product/B00F1YQMXO/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&psc=1
and it works perfectly without an modification other than cutting a slot in the male end to accommodate the connector keys in the chassis.


scm@...
 

If you search on eBay (Search terms: jamma harness,56). you will find many priced $12.00, or so and up, including shipping.


Harvey White
 

Some JAMMA harnesses have pin 7 missing.  This will prove a problem when the harness is inserted with pin 1 connected to pin 1.  In the TM500 series, from pin 14 on are not dedicated lines, and are used only to connect one plugin to another on the back panel.  Reversing the harness will place the missing pin in this group and you should be able to use the JAMMA harness for power connections.

Harvey

On 7/25/2020 5:37 PM, scm@... wrote:
If you search on eBay (Search terms: jamma harness,56). you will find many priced $12.00, or so and up, including shipping.



Vince Vielhaber
 

Just be careful of the upper pins on the JAMA extenders. Some have the a number of the A and B tied together. I didn't notice it and toasted a plugin.

Vince.

On 07/25/2020 05:37 PM, scm@... wrote:
If you search on eBay (Search terms: jamma harness,56). you will find many priced $12.00, or so and up, including shipping.


Harvey White
 

Ouch, didn't realize that.  If I did a board for the TM500 series (or TM5000), I'd be designing the board myself, and not using JAMMA adaptors.

Thanks.

Harvey

On 7/25/2020 7:54 PM, Vince Vielhaber wrote:
Just be careful of the upper pins on the JAMA extenders.  Some have the a number of the A and B tied together.  I didn't notice it and toasted a plugin.

Vince.

On 07/25/2020 05:37 PM, scm@... wrote:
If you search on eBay (Search terms: jamma harness,56). you will find many priced $12.00, or so and up, including shipping.



John Griessen
 

On 7/25/20 8:44 PM, Harvey White wrote:
If I did a board for the TM500 series (or TM5000), I'd be designing the board myself,
There is pcb-rnd editable data and rs274-x fabbable data for this available free by asking me:
https://www.ecosensory.com/tek/tek_tm_flex_pcb_bot.jpg
https://www.ecosensory.com/tek/tek_tm_flex_pcb_top.jpg

and it fits in TM500s TM5006's fine.


Harvey White
 

Thanks, already took a morning and went past that point.  All pin breakouts, LM7805 regulator and included 3.3 volt regulator if needed.  Idea was not to make extenders (although this could be the start of one), but a plugin/supply board I can use to power a project in a TM500 frame.  Most of my designs use a 5 volt bulk supply, which may power the I2C off board interface, and on board 3.3 volt regulators that power everything else.

Something might come of this,  for example, the module slot tester that Tektronix made, but I don't need the +5 and +/- 15 volt supplies.  Do need lots of binding posts, though.

Harvey

On 7/25/2020 11:05 PM, John Griessen wrote:
On 7/25/20 8:44 PM, Harvey White wrote:
If I did a board for the TM500 series (or TM5000), I'd be designing the board myself,
There is pcb-rnd editable data and rs274-x fabbable data for this available free by asking me:
https://www.ecosensory.com/tek/tek_tm_flex_pcb_bot.jpg
https://www.ecosensory.com/tek/tek_tm_flex_pcb_top.jpg

and it fits in TM500s TM5006's fine.



Colin Herbert
 

I have a couple of the Dan Meeks extenders, which are rather more useful. They have better module and mainframe connections and have test-points, jumpers and tell-tale leds for 25VAC "A" and "B", 11.5VDC, and 17.5VAC and +/-26VDC. They use a ribbon-cable for the interconnection and are a work of art. However, if you want to check whether the pass-transistors are working or not, you still have the fiddly problem of making connections to two sides of the female connector at the same location. My idea is to bring out a number of the back-plane connectors to a front panel so that they are easily accessed for checking. I think Tek made a module that would do something like this, but I have never seen one (067-1201-99 ?).
Colin.

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of DaveH52
Sent: 25 July 2020 19:52
To: TekScopes@groups.io
Subject: Re: [TekScopes] Dead TM500 plug-in sought

I bought one of these to act as an extender:
https://www.amazon.com/gp/product/B00F1YQMXO/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&psc=1
and it works perfectly without an modification other than cutting a slot in the male end to accommodate the connector keys in the chassis.


Harvey White
 

That's the exact thing.  +5 volt supply and uses the pass transistors to do a +/- 15 volt supply.

You were supposed to build one yourself if you needed it, I don't know that TEK ever had them for sale.  A simpler design would be the connector, banana jacks for the raw voltages, and bringing out the pass transistors to binding posts for an external transistor tester.

Harvey

On 7/26/2020 3:35 AM, Colin Herbert via groups.io wrote:
I have a couple of the Dan Meeks extenders, which are rather more useful. They have better module and mainframe connections and have test-points, jumpers and tell-tale leds for 25VAC "A" and "B", 11.5VDC, and 17.5VAC and +/-26VDC. They use a ribbon-cable for the interconnection and are a work of art. However, if you want to check whether the pass-transistors are working or not, you still have the fiddly problem of making connections to two sides of the female connector at the same location. My idea is to bring out a number of the back-plane connectors to a front panel so that they are easily accessed for checking. I think Tek made a module that would do something like this, but I have never seen one (067-1201-99 ?).
Colin.

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of DaveH52
Sent: 25 July 2020 19:52
To: TekScopes@groups.io
Subject: Re: [TekScopes] Dead TM500 plug-in sought

I bought one of these to act as an extender:
https://www.amazon.com/gp/product/B00F1YQMXO/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&psc=1
and it works perfectly without an modification other than cutting a slot in the male end to accommodate the connector keys in the chassis.







 

On Sun, Jul 26, 2020 at 09:35 AM, Colin Herbert wrote:


My idea is to bring out a number of the back-plane connectors to a front panel so that they are easily accessed for checking.
A couple of other things you might want to check while you are at it are the three 25 VAC windings:
I do recall (at the moment though I can't find the specific info) that some early mainframes could have
been incorrectly wired in manufacturing, i.e. some windings were wired backwards causing the phase
between windings to be 180 deg off.
Also check that the windings really are floating. Some time ago I had a mainframe that would damage
the plugin in one of the compartments and it turned out to be also a manufacturing defect. One wire
of one of the windings had been stuck in the frame causing contact to ground so that 25VAC was not floating.

/Håkan


Colin Herbert
 

I knew there were two 25VAC windings per bay, but three? I'll have to have another look.

Oddly enough, I have a TM504 (with option 2, Serial # B033988) and a DM502 that were puzzling me recently. The DM502 wouldn't work at all in the TM504, but it was fine in my two TM503 mainframes. All of my other TM5xx modules worked in both. I was scratching my head and though it might be something relating to Option 2, but no wires were connected when I checked it. Then I noticed that the DM502 uses two of the 25VAC windings in series going to a transformer inside it. I then recalled that I'd read something about the 25VAC windings being out-of-phase in earlier TM5xx mainframes, so I checked it out. Sure enough the 25VAC windings in each of the four bays in my TM504 were out-of-phase with each other. A bit of fiddly de-soldering and re-soldering cured that and all of my TM5xx modules now work in all three TM5xx mainframes.

That TM503 weighs a bit when fully populated!

Colin.

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of zenith5106
Sent: 26 July 2020 16:51
To: TekScopes@groups.io
Subject: Re: [TekScopes] Dead TM500 plug-in sought

On Sun, Jul 26, 2020 at 09:35 AM, Colin Herbert wrote:


My idea is to bring out a number of the back-plane connectors to a front panel so that they are easily accessed for checking.
A couple of other things you might want to check while you are at it are the three 25 VAC windings:
I do recall (at the moment though I can't find the specific info) that some early mainframes could have
been incorrectly wired in manufacturing, i.e. some windings were wired backwards causing the phase
between windings to be 180 deg off.
Also check that the windings really are floating. Some time ago I had a mainframe that would damage
the plugin in one of the compartments and it turned out to be also a manufacturing defect. One wire
of one of the windings had been stuck in the frame causing contact to ground so that 25VAC was not floating.

/Håkan


 

On Sun, Jul 26, 2020 at 08:08 PM, Colin Herbert wrote:


I knew there were two 25VAC windings per bay, but three? I'll have to have
another look.
Yes you are right, my mistake.

/Håkan


Harvey White
 

No, there's two per bay, but one set is high power.  They're all 500 ma except the odd ones that go to the high power bay that are rated at 1 amp each winding.  There is a high power 17.5VAC winding that supplies the high power compartment, from it is derived the (separate for high power compartment) 11.5 vdc. The lower current 17.5VAC winding supplies AC and 11.5 VDC for the other compartments.

On the backplane, there can be a cutout that allows a plunger to go through, said plunger is connected to a switch in the plugin, which is how the plugin knows it's in a high power bay.  Don't remember what the default is, though.

For weight, try a TM506 or a TM515.

Earlier mention:  I'd plans to bring out the windings to binding posts, but I wasn't sure how complicated I wanted to make the thing, let alone how much front panel space there is.

One simple option is just binding posts.

Another option is relays, microprocessor, display, and a few other goodies.

You could make a phase detector by shunting the diode in an opto isolator with a reverse diode, adding a suitable series resistor, then connecting all the B ends of the windings with similar opto isolators.  Wonder if cross connecting A to B might work as well. You should have voltages, if not, then phases are wrong and windings may be shorted.  Nice thing is that this works out to a bunch of digital lines that can be monitored easily.  Hmmm, op-amp rectifier driving processor A-D through buffer amp.  Touch display if needed.

maybe.....

Harvey

On 7/26/2020 2:08 PM, Colin Herbert via groups.io wrote:
I knew there were two 25VAC windings per bay, but three? I'll have to have another look.

Oddly enough, I have a TM504 (with option 2, Serial # B033988) and a DM502 that were puzzling me recently. The DM502 wouldn't work at all in the TM504, but it was fine in my two TM503 mainframes. All of my other TM5xx modules worked in both. I was scratching my head and though it might be something relating to Option 2, but no wires were connected when I checked it. Then I noticed that the DM502 uses two of the 25VAC windings in series going to a transformer inside it. I then recalled that I'd read something about the 25VAC windings being out-of-phase in earlier TM5xx mainframes, so I checked it out. Sure enough the 25VAC windings in each of the four bays in my TM504 were out-of-phase with each other. A bit of fiddly de-soldering and re-soldering cured that and all of my TM5xx modules now work in all three TM5xx mainframes.

That TM503 weighs a bit when fully populated!

Colin.


-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of zenith5106
Sent: 26 July 2020 16:51
To: TekScopes@groups.io
Subject: Re: [TekScopes] Dead TM500 plug-in sought

On Sun, Jul 26, 2020 at 09:35 AM, Colin Herbert wrote:

My idea is to bring out a number of the back-plane connectors to a front panel so that they are easily accessed for checking.
A couple of other things you might want to check while you are at it are the three 25 VAC windings:
I do recall (at the moment though I can't find the specific info) that some early mainframes could have
been incorrectly wired in manufacturing, i.e. some windings were wired backwards causing the phase
between windings to be 180 deg off.
Also check that the windings really are floating. Some time ago I had a mainframe that would damage
the plugin in one of the compartments and it turned out to be also a manufacturing defect. One wire
of one of the windings had been stuck in the frame causing contact to ground so that 25VAC was not floating.

/Håkan







Ke-Fong Lin
 

Earlier mention:  I'd plans to bring out the windings to binding posts,
but I wasn't sure how complicated I wanted to make the thing, let alone
how much front panel space there is.
Hi Harvey,

You may want to take a look at my extender project: https://github.com/anotherlin/tek_tm_ext
The intention was originally about doing the opposite, being able to supply plug-ins with controlled sources (bench supplies) of voltages for debugging/repair purpose.
However, the Molex connectors can be used to "probe" the mainframe itself.
It is probably much more "lower level" than most other TM500/TM5000 extender offering.

Best regards,


Harvey White
 

Thank you, that gives me a few ideas, although I've gotten to that point already.  I'll have to give JLPCB a try.  I've been using Seeedstudio for boards, but they have a rather draconian price increase at boards bigger than 100 mm by 100 mm in any direction.

I've been designing PC boards in EAGLE for a number of years, so the design process isn't really a problem.

The 7000 series extender boards I did had ribbon cable, and doubled the wire for each pin to lower resistance.  Not something you could do a calibration run on because of the lack of coax, but you could do a lot of debugging.  The 500 series doesn't run high frequency signals though 1-13, and 14 on is anyone's guess.

Harvey

On 7/26/2020 3:59 PM, Ke-Fong Lin wrote:
Earlier mention:  I'd plans to bring out the windings to binding posts,
but I wasn't sure how complicated I wanted to make the thing, let alone
how much front panel space there is.
Hi Harvey,

You may want to take a look at my extender project: https://github.com/anotherlin/tek_tm_ext
The intention was originally about doing the opposite, being able to supply plug-ins with controlled sources (bench supplies) of voltages for debugging/repair purpose.
However, the Molex connectors can be used to "probe" the mainframe itself.
It is probably much more "lower level" than most other TM500/TM5000 extender offering.

Best regards,