Extending the BFC cable

[Y-my-R]

OK, here's an update to the inquiry with Kemcor, if they could make longer Console/Rack connection cables (the 18-core cable with the BFC that connects to the rack unit internally):

1. Kemcor is generally willing to do that, but needed permission from Mackie/Loud

2. Permission from Mackie/Loud was obtained and sent to Kemcor. (Crash and I know people, who know people. And apparently the people we know, and the guys at Loud/Mackie are pretty cool!).

3. Kemcor sent a quote for BULK cable and a minimum order quantity/length of 1000 Feet. Bulk means that it’s just one super-long such cable, probably on a reel.

4. When adding taxes and shipping for the big reel of bulk cable to a single location, you’d probably pay around $250 (US-Dollars) for each 50 foot section of the cable. This is a rough guess. I’d need more information about the total weight of the bulk cable, before I can really make a guess about the added shipping cost.

5. Payment would need to happen upfront. So, IF we were to get 20+ people together who’d each want to get 50 feet worth of bare umbilical D8B cord, it would all need to be collected upfront and paid upfront. Then we’d wait for 4-5 weeks for the long cable to be manufactured.

A couple other caveats:
- Kemcor keeps talking about a 19-core cable (instead of the 18 cores I counted, but maybe they count the shielding or something). They didn’t answer my request clearly, if this is the same original cable with the original specs or not. This creates quite a bit of a risk, IMO. Which leads me to the next caveat.
- Mackie only gave permission with the explicit warning, that they can’t guarantee that a longer cable of the same type would even work. Well… the good side to that, is that I have a 50 foot cable already, and could test before ordering.
- Kemcor ALSO doesn’t give a guarantee that the cable will work for the intended purpose. And for a 1000 feet bulk cable that costs several thousand dollars in total, that’s a bit TOO MUCH of a risk, IMO. And the 18-core/19-core discrepancy in the first caveat makes me really nervous about that.

In short: Unless there’s 20+ lurkers on here who TOTALLY want to spend the $250 or so upfront, and then wait if the new longer cable will work for them, after transferring the BFC and other connectors over from their own (shorter) cable to the longer cable, this whole thing doesn’t really make a whole lot of sense. Especially with the risks involved, that may end up in this not being a solution at all.

So, to get an idea where we’re at, could everyone who would be interested in chipping in around $250 for a group order of 1000 feet of bulk cable please raise their (virtual) hand?

I know this is unlikely, but I at least wanted to bring this topic to closure. If there IS that much interest in longer D8B umbilical cords, then we can figure out the details, then (i.e. who facilitates/orders/receives, etc. - I already have a 50 foot cable, so, probably not me).

Thanks!

[Y-my-R]

FYI, I attached the 50 foot umbilical cord to a spare rack unit, and tried it with a spare console...

It works fine, passes audio and sounds clean! So, the long cord WORKS and the cable length doesn't seem to cause an issue.

I don't have such a long 25-pin D-Sub cable (Parallel/Serial), but connected the 3 spare ones I had lying around together, for a length of about 30 feet (more like 29 1/2 or so). This also worked without problems (I tried that after I took the pic below, though).

What sucks, but that's my own problem, is that the first spare console I tried, didn't pass any audio - even though it did when I decommissioned it. Of course I was troubleshooting everything else first, before trying my 2nd spare console (I have 3 D8Bs in total), and that one worked and passed audio. I guess the consoles really don't like to sit unused and will develop problems. I think it's been less than a year since I "parked" that one. Weird...
In the one that works, I also first had stuck meters on several channels and it wouldn't respond. I shut it down and pulled the two I/O cards out that I had in that one, started again, and then it worked. So, that one also wasn't happy about being stored, I guess... but at least it still passes audio. (It was decommissioned at the same time... I fixed up the 3rd console when I bought it, and used that as my main one, removing the other two).

Oh... and just for the sake of it, I did try all the Line inputs and they all worked. Didn't test all the inserts, etc., but don't see why that would be a problem because of the longer cable.

But anyway... the 50 foot cable works, and a longer 25 Sub-D cable run is apparently also not a problem.

Here's a pic to show that I'm not making this up

D8B_50foot_cable_works.JPG (Array KiB) Viewed 2191 times

[captainamerica]

Well done!

[captainamerica]

BTW: sent you a message and hope you got it

[captainamerica]

Got the cable today and plan to test things later this month - once I move the studio console. Thanks Y-my-R

[captainamerica]

Good news: my new 50feet Mackie extender cable for my console works! This will allow me to run from my machine/server room back to the main control room ...a key piece in the equation of isolating computer noise fan stuff out of the control room and helping with acoustics. Thanks to Y-my-R (and Troy) for helping me get this cable.

...now on to item 66 on my list of things to do today

[Y-my-R]

Awesome! Happy to hear that it works! (Didn't expect that it wouldn't, though).

Curious to see pictures once you rearranged the studio in the way you needed the longer cable for!

To give others who read this some context:
We did NOT get a new batch of longer cables made, since nobody raised their hand and the minimum of participants in this wasn't reached.

However, while trying to get approval from Mackie to have one of their OEM suppliers make a new batch of such cables, a Mackie employee shared that he happens to have a single one of these longer umbilical cords lying around, still. That's the cable Captain America ended up with.

As posted earlier in this thread, I have another 50 foot cord like that myself as well... but it's the only two in existence that I'm aware of. I tried to find out how many of these "prototype cables" were made, but didn't get an answer.

[Y-my-R]

Besides the small possibility of a 50’ BFC cable going bad from lying on a shelf for a few months… can anybody think of a reason why that cable would work fine during extensive tests some months back, but would NOT work to power a D8B console anymore, when trying to deploy that kind of configuration?

I had that 50 foot cable for a long time, and tested it soon after I got it. Worked fine. Now I finally have a space that can serve as a machine closet, and wanted to move the D8B CPU in there. So, I got out that rack unit that has the long cable attached to it, but it no longer works to power the console (the OS boots to where it can, without finding the console).

I have 3 consoles and tested it with 2 of them… but there’s a bit of a history that I should get out of the way:

At some point (...and I'm not even sure why... but there was a reason), I replaced the ENTIRE power supply in that rack unit that is planned to go into the machine closet (old board), with a complete set of power supply components from another unit (that had a burned out keyboard controller on the mainboard). So, everything under the lid on the left side of the rack unit, was replaced with components from another unit.

However, when I swapped those components, I made a GRAVE mistake: I apparently didn’t pay enough attention, and had the “brown” cable and the “black” cable coming from the AT power supply reversed. So, brown was connected to black on the distribution board, and black was connected to brown (…or do they supply the same voltage?).

When I powered on the D8B, the console lit up all the meters from channels 13 and up and they stayed on (…until I quickly switched off).

Like an idiot, I didn’t even consider that I could have made a mistake with the wiring, and just connected my 2nd spare unit, to see what that does. That one was flashing the meters for channels 13 and up (so, same meters lit up, but flashing instead of being constantly lit).
It’s been a while and I’m confused now… but after a lot more troubleshooting, one of those units now flashes the meters, and the other just stays dark (but an LED on a card in the card cage blinks, so it’s not quite dead).

I would have thought that this means that I just managed to fry not one, but TWO of my D8B consoles, but here’s the kicker:

When I remove the 50 foot BFC cable from that unit, and attach a “stock” BFC cable, both of the consoles I had tested with, boot up normally and work fine.

So, the most likely culprit would be the cable, so I measured each wire in the long BFC cable with a multimeter (Ohms), and the all show good contact. I also checked if I get a reading at more than one destination with each cable… but don’t.
Not sure if there’s a better way to check for a short, but at least, each contact only gives a reading on one end.
The shield and BFC have good contact, all the way to the rack unit's case.

I’m not sure how to continue… I guess I could apply voltage to each of these wires (one at a time) and test if I see more of a voltage drop on one of the wires compared to the other, to see if it “escapes” to somewhere via a short or something (…is this feasible? Does this make sense as a test?), but I suspect that the problem started, when I had those power supply wires switched, and that I might have blown something out in the console, on the 2 units that I tested. Is this possible?

I do have a 3rd unit (my main one) that I could still test with, but am rather hesitant to do that. I’m a bit worried that something in the power supply may have fried, that then takes out whatever is causing the problem on a connected console unit. So, I’m not sure about the next step.

Again, the rack unit I intended for the machine closet works fine with a "stock" BFC cable, but flashes (or constantly lights up) the LED meters with the long cable.
(Sometimes it flashes the same channel meters for a split second, when starting with the stock cable, but just for a very short moment... that's why I'm thinking it might be insufficient power and it doesn't get past that point when trying to start up the console...?)


Long story short:
Is there anything power supply related on the console side, that could result in the console not getting sufficient power? Especially, if the power skews on the low side, as might happen due to power drop from a longer than usual BFC cable?
Something like a large capacitor or voltage regulator or something, that could cause this kind of situation if not operating within the tolerance?

Again, it could just be a bad long BFC cable in the end… but I still suspect that I managed to damage the same component in both units I’m testing with… so I thought I better ask the hive mind, here!

(I don’t really want to take any risks with my main unit right now… but could do comparative measurements etc. I just don’t want to connect possibly bad system component to my main system for troubleshooting right now, since everything otherwise works exactly as it should… it’s just the CPU noise I’d like to finally eliminate via the long cable and machine closet).

Thanks very much in advance for any suggestions you can give!

[Jondav1120]

Hi Y-my-R,

How long is your serial data cable? The D8B runs the serial links quite fast (19200 Baud - from memory), and you could well be approaching the maximum distance at this speed. I'd suggest trying the long power cable with the standard data cable.
Is your long data cable of decent (low capacitance / meter) construction and screened? Could be data corruption either from length (signal loss) or external interference.
I have never ripped apart one of those 25pin - 25pin serial cables to see what the cable construction is, but I suspect it is nothing special. Certainly the internal wiring of the cpu and the console is simply ribbon cable, no twisted pairs in sight!

Regards

John

[Phil.c]

This might be a stupid question...probably is to some of the tech wizards here but wouldn't a multi-meter at the end of that long cable tell you what voltage you are getting...or not getting?