ADC Patchbay Wiring Question

[Siegfried Meier]

I have one of those punch block terminal ADC bays that have the TRS plus the TN and RN connections (5 in total for each point).

Now, in order to normal the top (1) and bottom (49) points of the bay, should I not have to simply connect the TN of 1 to the TN of 49, and RN of 1 to the RN of 49? I've tried this on several points and it doesn't work - I still have to manually patch to make the signal get from 1 to 49.

Any help is much appreciated.
Thanks,
Siegfried

 

[sodderboy]

You want to punch top T to bottom TN and Top R to bottom RN. That is for a half-normalled bay.
For a fully normalled bay, you would do what you say you have been doing. What happens if you test from the other ends of your cabling with a cable tester?
Mike

 

[NewYorkDave]

Are these mics? If so, you have to punch down a wire between the upper and lower "S" terminals. Without continuity of the shield, un-powered mics will be noisy and phantom-powered mics won't work at all.

 

[Siegfried Meier]

Take a look at the pic below.

Now, I'm very confused on how to wire this correctly. I have my Snake Out 1 wired to "1" of the bay, and my first Mic Pre In wired to 49, which is the bottom patch point, but happens to be beside it on the rear view. And to answer your question, yes, this is for a 24 channel mic snake to be wired permanently to the bay, and normalled to mic pre ins.

I want the Snake Out normalled to the Pre In, and I'd like to break in to the Pre In for outboard gear. Am I looking for half-normalled, or full? And what do I do? Seems I've tried everything and I still have to patch.

Thanks so much!
Sig

 

[pucho812]

hmmm.... O.k. Unless you wanna be bass acwards or anything of the sort, The mic pannel from the room to the mic pre should always be a full normal. Never do a half normal on those patch points.

Follow this diagram from ADC on how to normal via punchdown block'


http://www11.adc.com/srvs/Data/Products/Knowledgebases/bcg_broadcast/document/audio normalling.pdf

 

[Siegfried Meier]

So according to this document, and what you're saying, I don't even use the TN and RN at all if I want fully normalled connections? And why exactly not a half-normal? Is it because of a phantom power issue and shorting something out?

So what then, as I don't fully see which ones, do I connect to do what I want to do in the photo above?

Thanks so much for being patient.

Siegfried

 

[NewYorkDave]

Mics should be full-normalled.

Connect TN(1) to TN(49)
Connect RN(1) to RN(49)
Connect S(1) to S(49)

Repeat above for (2) and (50), and so on...

 

[pucho812]

maybe the wrong document. What patchbay is it what is the model number. Wiring patch bays is a pain. so I know how you feel. If you can buy prewired if you can't then suffer like we have so many times before.

But the info is out there. IF we had a model number, etc we could find the exact wiring diagram for ADC. I usually use a different patchbay company but I won't get into that.
So model number and such and we go from there.

Edit: dave beat me to it. Go dave :thumb:

 

[NewYorkDave]

By the way:

Use only the proper punchdown tool from ADC. Kludges may work in an emergency but will easily wreck the terminals.

Don't ever punch down bare stranded wire, the strands will disintegrate. The shield connections should be covered with a piece of spaghetti tubing before punching down. A package of these is included with every new ADC patchbay.

 

[Siegfried Meier]

Thanks for the help. I wired the bay as you suggested before I posted to this board, and it doesn't work. So I am at a loss here. The only solution I can think of is to always patch in the snake to the mic pres. The normalling just doesn't work.

Siegfried

 

[NewYorkDave]

You DID connect S-1 to S-49 (and so on), right? I keep bringing this up because you haven't indicated if you did that or not. It's crucial, especially for phantom-powered mics which simply will not work otherwise.

It's unlikely that ALL the normals could be bad, but you already reported having the same problem in several positions. Is the punch panel mounted on the rear of the patchbay, or is it separate? If connecting the shields as above doesn't work, I guess what I'd probably do at that point would be to pop the lid off and make sure the normals on the jacks are actually wired up to the punch panel. It sounds weird, I know, but as they say: "never assume."

 

[Siegfried Meier]

Yeah, I've connected the shield and all I seem to get is a nasty hum/buzz. I'm gonna pop the top off this thing and take a look, although I'm not really sure exactly what to look for here. It sucks if I have to always patch the mics into their respective pres, but it'll work I guess.

BTW, the punch panel is on the rear of the bay.

Question, if I put a meter across the TN of 1 and the TN of 49, shouldn't I get continuity?? I'm not getting that on anything. Problem with pulling the top off now, is that I've half wired the damn thing in, and I can't get it out of the rack to take the top off. Why would anyone disconnect this functionality inside the box though? Seems really stupid.

Thanks,
Siegfried

 

[Siegfried Meier]

Ok, it took pulling the entire bay out to find out exactly what I was doing wrong, and it's really really dumb. I've never had to wire these TN's and RN's before as my other bays are wired internally and don't have these. So, I thought just connecting them from left to right would work. But, alas, you HAVE TO LOOP the wire around the points, as only the bottom left hand corner has the slit where the wire gets cut, which I know but just completely overlooked. So, what was happening was I was cutting the wire off on the top right hand side each and every friggin' time!! The bay was deep in the rack under 2 other bays, and I just couldn't see properly and I just wasn't thinking. SO, I think this has solved the problem, and I very much appreciate everyone's help on this one. And, I learned quite a few things too, like connecting the shields for phantom, and using that spaghetti stuff on the grounds (I used to just bunch it up, or solder just the ground, which worked too).

Thanks again,
Siegfried

 

[NewYorkDave]

I may have made the same mistake the first time I wired up an ADC patchbay. They were quite different from the "66" blocks I'd worked with before then.

The ADC punchdowns are great, though. Once you're used to them, you'll never want to go back to soldering a patchbay.

 

[pucho812]

[quote author="NewYorkDave"]
The ADC punchdowns are great, though. Once you're used to them, you'll never want to go back to soldering a patchbay.[/quote]

I've soldered a few Patchbays in my time :sad: IS all I will say on that.

Worse is when the patchbay terminates to 3 pin elco connectors. I understand why as it does save space and potentially in a 2 RU pannel you can have 96 connections the size of a 1 RU TT bay with 96y points. But a pain none the less.

 

[SSLtech]

Don't make me post it again...

(...-I will, you know!)

All of your solder patch are own by us.

Keef

 

[NewYorkDave]

I like bays that terminate in "Christmas Tree"* blocks, actually... There's the reliability of soldered connections but with the convenience of having the connections brought out to a more convenient location. But that's a sort of old-fashioned arrangement that's rarely seen nowadays.

I've soldered up my share of "bare jacks" patchbays, but I ended up terminating the other end with... a punchdown panel :grin: I like to be able to reconfigure connections without yanking the patchbay out of the rack.

But anyway, the ADC punchdown type are very good, IMHO

* For those who've never seen a "Christmas Tree" block, here's the only picture I could find on the web:

http://www.bigdmc.com/patchbay.html

Mounting the block directly on the back of the patchbay is unusual. Usually, the block is separate and connected to the patchbay by a thick umbilical.

 

[Siegfried Meier]

[quote author="SSLtech"]Don't make me post it again...

(...-I will, you know!)

All of your solder patch are own by us.

Keef[/quote]

What the hell was this again??

 

[pucho812]

Keith has a pic of some patchbay work he has done. It's quite a photo :thumb:

 

[NewYorkDave]

Here's a handy tip: get into the habit of closing your eyes as you drive the punch home. Usually, the cut ends of the wire just fall away harmlessly--but every now and then, one flies right at your face.

Now that you've mastered ADC patchbays, wanna come to New York for a few days and help me with this project? :green:

(This is just one of several jobs I'm trying to tackle during the "holiday slowdown" :?).