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[Gerard Visser <gvisser AT indiana.edu>]

hi Mike,
        Just got the cable sample from you -- thanks!
	Looks pretty nice in genral, except the twisting of pairs is VERY loose, 
unexpected. I think we may need to look into this a bit. There are two possible 
issues:

- The possible minor issue is that it may be very difficult to figure out what 
is what and keep the pairs reasonably together, when terminating this cable. 
(Send some to KC if they don't already have a piece. This is only a possible 
headache for assembly. The wire length outside the jacket should be pretty small 
(inch or two) and keeping the pairs together in that inch or two would be best 
but is not critical.

- A possible major issue is if the pairs don't really lay as pairs in the length 
of the cable. [Dissecting a short piece it didn't look so good - but it is hard 
to really tell with a short piece.] Then there will be horrible crosstalk and 
reflections and we probably can't have that. We're going to have to bump up the 
priority of maklng some signal integrity / impedance measurement test on this 
cable. I had thought of that as something I would do because we should test it 
and know the right impedance value, but now it is more urgent we may have to 
decide go/no-go on this cable. Maybe you can try such a test too please? I am 
swamped here I will try something simple soon, but it may still take a bit.

        Gerard


On 1/7/2020 2:39 PM, Capotosto, Michael wrote:
> Gerard, Flemming, Robert, and All,
>
> I’ve received the reel of cable yesterday, 1,100ft. I’ve opened up a short 
> piece, it appears to be correct. 36 conductors, plus a drain. We have an outer 
> foil shield with no braid.
>
> Please let me know what lengths you all need for testing, and where to send it  
> (and how urgently you need them shipped).
>
> The V3 T-Boards have been shipped FedEx overnight last night, but FedEx had a 
> delivery exception, it arrived late to the local hub. I should have it tonight 
> or tomorrow morning. I just need to put the Nicomatic connectors onto the 
> boards, I will be able to have them to our cable vendor by Thursday afternoon so 
> he can begin putting the D-Sub connectors on one end, and soldering the opposite 
> end to the T-Boards.
>
> Gerard,
>
> I’ve placed the order for the machined pins, I ordered 1,850 (Enough for 45 
> assemblies, plus 10%). They should arrive some time in March (11 weeks). The 
> housing was a stock item, but they were cheap so I ordered them to be sure we 
> have them. The backshells we used for the V2.1 test stand cables are very large 
> on this new cable. We have four pieces of backshell 8655MH2511LF – Steve 
> Valentino purchased these, however the clamps did not fit with the V2.1 test 
> cables. These backshells now fit very nicely with the clamps and jack screws. 
> They also fit the PPB/Patch Panel without interference. I’ve ordered 6 more, so 
> we can keep it consistent across the 10 test stand cables. I’ll wait until the 
> finished cables go out before I order production quantities of backshells, so 
> everyone can share your thoughts on them.
>
> Thanks,
>
> Mike Capotosto