The unobtanium connector of Solartron 7061, what to do, please help ?

[Neomys Sapiens]

Have you tried ODU? they are the third manufacturer of connectors with this coupling system, besides Fischer and Lemo.

https://www.odu.de/

[tggzzz]

I bodged a male connector to fit into the front panel socket. Using my 7 decade 100kohm KVD driven by a 10V source, and my 7081 in ratio mode, the combination shows a linearity of 1ppm to 2ppm except for the 6666666 KVD setting, where it is 2.8ppm deviation.

Key points of the bodged connector:

• the pins have to be 1.35mm diameter, and it is a pain finding that. I've found two options: an RS211-4252 ferrule, or some PoGo pin shanks (last picture)
• the pin location is determined by holes in a PTFE sheet. Drill the holes undersized; the PTFE is soft and can easily be deformed by the pin. My sheet is 1mm thick, which is too thin; 2mm would be better
• the connector body is a copper plumbing pipe, external diameter 12mm. Obviously it does not latch into position

A little ingenuity is required to create a connector body where the PTFE insert is held in fixed position relative to the connector body. I simply made the PTFE insert have a 12mm diameter, and sandwiched that between two 12mm OD copper pipe sections. Those two sections were held together with a copper pipe with internal diameter of 12mm.

It might be possible to create an insert for a real connector body, using PTFE and the pins. I suspect the challenge would be to ensure the insert cannot slide up and down inside the connector.

[DC1MC]

Have you tried ODU? they are the third manufacturer of connectors with this coupling system, besides Fischer and Lemo.

https://www.odu.de/

Thanks NS for the tip, it seems that ODU F-series has at least a similar looking footprint and pin size.

 @tggzzz, or who has an eye for the mechanical layout, could you please verify if the layout is similar, as far as I remember the l original connector, was not only mechanically keyed on the outer shell, but it also has a different spacing between the rows of pins.
BTW @tggzzz, it's a nice connector that you've build there, but I don't have the skillz, even if I have some pogo pins somewhere.

The ODO datasheet for the F-series is at:
https://www.odu-uk.co.uk/fileadmin/redaktion/downloads/downloadcenter/catalogues/ODU_MINI-SNAP_F_Circular_Connector_Series_F_EN.pdf

The suitable pattern seem to be on page 26, but I have just a faint clue how to build the right plug code out of all these options, if someone more experienced could lend a hand, it will be very nice if we can close this topic, Solartrons 70xx series are nice instruments IMHO and deserve a nice test lead.

 Cheers,
 DC1MC

Ninja Edit: Sheeeit, looked at the Digikey prices: 50EUR+, no rest for the poor  , probably were used on some military or aerospace application in the '80ies and bam, 600% price increase for a connector with a production prices in single euros, if so 
https://www.digikey.com/products/en/connectors-interconnects/circular-connectors/436?k=&pkeyword=&pv28=1214&pv88=24&FV=fffc0773%2Cffe001b4%2Cffecf2e5&quantity=0&ColumnSort=0&page=1&pageSize=25
And nothing is stocked, those Digikey guys are smart.

[DC1MC]

I got the same problem. Just got a Solartron 7061 but can't find the connector.

So I'm planning to replace the probe connector by this one: https://www.ebay.ca/itm/1Set-8mm-9mm-10mm-12mm-XLR-Aviation-Panel-Chassis-Metal-Quick-Fast-Connector/321605780222?ssPageName=STRK%3AMEBIDX%3AIT&var=510491955786&_trksid=p2060353.m2749.l2649

I figured it was easier and less destructive than drilling 5 holes for some banana plug connector.

Still waiting for the connector from ebay thought.

Is this guy you've showed me fitting in the exiting connector ?!?!? Or do you plan to replace the socket as well, where did you get the counterpart ?

Cheers,
DC1MC

[tggzzz]

@tggzzz, or who has an eye for the mechanical layout, could you please verify if the layout is similar, as far as I remember the l original connector, was not only mechanically keyed on the outer shell, but it also has a different spacing between the rows of pins.

Both are correct.

There are two groups of two pins on a circle centred on the middle pin. One group has a narrower gap than the other.

My connector ignored the mechanical key. It is thus mechanically adequate rather than good. The pipes are a reasonable electrical/thermal approximation to the real connector.

BTW @tggzzz, it's a nice connector that you've build there, but I don't have the skillz, even if I have some pogo pins somewhere.

Neither did I - before I was forced to make that connector.

[shakalnokturn]

You could try asking Dave (C) Partridge he's quite a fan of the better Solartron stuff, no idea if he is active on this forum but he maintains a Solartron group on groups.IO.

His website:
http://www.perdrix.co.uk/Solartron7081/index.htm

[Kosmic]

Is this guy you've showed me fitting in the exiting connector ?!?!? Or do you plan to replace the socket as well, where did you get the counterpart ?

I'm planning to replace male and female connectors. They sell them in pair. I ordered 3 pairs so if everything is going well I should be able to replace the connector at the back too.

[Ero-Shan]

Wow.
I did not expect this to be so hard. Thought I could easily buy more such connectors.  Not so.

Makes me more than happy that my 7061 came with some kind of test leads:

[DC1MC]

Neither did I, or I would have bought the Slovakian 7071 with TWO sets of leads, one 2 wires and one 4 wires 

 DC1MC

[tggzzz]

Neither did I, or I would have bought the Slovakian 7071 with TWO sets of leads, one 2 wires and one 4 wires 

I'm not complaining about having to make a connector and lead. My 7081 cost me £75, plus £25 for a replacement smoke generator (the mains switch / voltage selector), and some time.

[DC1MC]

I'm not complaining about having to make a connector and lead. My 7081 cost me £75, plus £25 for a replacement smoke generator (the mains switch / voltage selector), and some time.

Oh well, at this price, considering that reasonable OK 7081 runs in between 1000-2000EUR, personally I would have splurged for some proper leads or connectors, to thank the gods of TE for the blessing  .

My 7061 costed so far 3 times that, so it will be defiled with some chinotronics to have a reason to buy a 7081  .

 Cheers,
 DC1MC

[Kosmic]

Is this guy you've showed me fitting in the exiting connector ?!?!? Or do you plan to replace the socket as well, where did you get the counterpart ?

I'm planning to replace male and female connectors. They sell them in pair. I ordered 3 pairs so if everything is going well I should be able to replace the connector at the back too.

I just measured the diameter of the connector in the 7061 and its around 15mm . The connector I ordered are 13mm. So it should fit nicely.

I'll try posting some pictures when I will be done with the mod.

[DC1MC]

Wow.
I did not expect this to be so hard. Thought I could easily buy more such connectors.  Not so.

Makes me more than happy that my 7061 came with some kind of test leads:

Hold on to it, or you'll double the device price or transform it in some kind of useless space heater with LEDs. If on the other side, want to try your drilling talent with a teutonian Bohrmaschine  and install some nice banana sockets, I call dibs on the leads  .

 Always giving useful advice,
 DC1MC

[DC1MC]

I just measured the diameter of the connector in the 7061 and its around 15mm . The connector I ordered are 13mm. So it should fit nicely.

I'll try posting some pictures when I will be done with the mod.

Hi Kosmic, could you tell us how is the connector fixed on the front panel, is a panel mount connector with nut and wires going to the board, or is a PCB mounted connector ?
Also can make some pictures around the connector area, my device is yet to come and I want to try and select something as well.

 Many thanks,
 DC1MC

[capt bullshot]

Fischer connectors - not compatible to anything else, and very expensive. They have more variants of connectors that you can ever count 

I'd recommend you to contact a german representative with a photo of the "Buchse" (and where it is used, maybe they can remember this customer Solartron) and your guessed type number. They should be able to figure out if this is the corrent number and may even sell you the plug in single quantities - but be prepared to pay a high price. Don't know if they deal with individuals, but back then in a former company we've bought these connectors directly from a representative in rather small quantities (some ten per order).

[perdrix]

Buy direct from Fischer - they will sell in small quantities - I bought 5 last time round and sold on three of them.

They are about GBP35 each, and Fischer has a minimum order value which was GBP150 when I last bought from them

David

[tggzzz]

Buy direct from Fischer - they will sell in small quantities - I bought 5 last time round and sold on three of them.

They are about GBP35 each, and Fischer has a minimum order value which was GBP150 when I last bought from them

David

That makes sense. I had considered doing that a while ago, but I wasn't sure of whether they had a resale value.

Now it appears they do have a resale value, it is definitely worth considering - but only if we coordinate amongst ourselves so that we don't all buy 5 connectors!

[voltsandjolts]

I ordered some other connectors from Fischer two weeks ago.
FYI Min order terms are:

Delivery batches lower than £250 will incur a delivery charge of £15.00
Carriage is Free of Charge on Delivery batches over £250
Minimum order value is £50 for connectors and £250 for cable assemblies

[Joel_l]

If you can find pins to fit the sockets, 3D print or mold a housing for them.

[frozenfrogz]

Just in case you do not already have all the files:

http://www.ko4bb.com/getsimple/index.php?id=manuals

Search for Solartron, you will find a copy of the detailed service manual, ROM files and a bunch of other goodies.

Kind regards,
Frederik

[Kosmic]

Hi Kosmic, could you tell us how is the connector fixed on the front panel, is a panel mount connector with nut and wires going to the board, or is a PCB mounted connector ?
Also can make some pictures around the connector area, my device is yet to come and I want to try and select something as well.
 Many thanks,
 DC1MC

So the front and back connectors are identical and they are panel mount with wires going to the board. Diameter is around 15mm.

I will post detailed pictures as soon as I get the replacement connectors from ebay.

in the meanwhile here's a picture of the back connector (took from some web page) that will give you a idea.

[BU508A]

I'd recommend you to contact a german representative [...]

Here you can find the contact details for Germany:
https://www.fischerconnectors.com/germany/de/locations/germany

And here for the UK:
https://www.fischerconnectors.com/germany/de/locations/united-kingdom

[tggzzz]

Front and rear connector receptacles, 7081.

Front connector access is cramped compared to the rear connector access.

[Ero-Shan]

Hi Kosmic, could you tell us how is the connector fixed on the front panel, is a panel mount connector with nut and wires going to the board, or is a PCB mounted connector ?
Also can make some pictures around the connector area, my device is yet to come and I want to try and select something as well.
 Many thanks,
 DC1MC

So the front and back connectors are identical and they are panel mount with wires going to the board. Diameter is around 15mm.

I will post detailed pictures as soon as I get the replacement connectors from ebay.

in the meanwhile here's a picture of the back connector (took from some web page) that will give you a idea.

So why not just dump them altogether and replace them by obtainable and affordable connectors from Lemo/Odu or whoever that fit into the hole? Not banana sockets, but push/pull connectors. Looks like the best way to go if you ask me.

[Kosmic]

Another option would be to redo part of the front panel and install some banana plug connectors.

Personally it's not something I considered since I kind of like the idea of a shielded cable going directly to the measurement point.