The Rockwell/Collins IC-10A Console Project

Hi all,

Thanks for being such a wonderful resource/community. I?ve been lurking around here for the last few months and I?ve been continually impressed with the quality of the dialog, the level of expertise, and the friendliness with which you all seem to treat noobs (like myself). I?ve been learning a ton, thanks to all of you. I?m hoping my first post will be one that keeps you interested!

Last year I built a small, one room studio in the basement of my home. I did a fairly good job on the construction ? good enough to keep most of the sound of the outside world out. In creating a quiet room I heard, for the first time, just how crappy most of my gear sounded.

Being of the DIY persuasion I?d been reading up here and trying to decide what kind of mic-pre project I should undertake first. I?d been leaning towards the JLM kits but holding back for a while to save up a bit of cash. Then last night, in one of my regular perusals of Craigslist, I found a post for a "Huge Old Radio Console."

Now I am the owner of a very heavy Rockwell/Collins IC-10A, a 10 channel stereo broadcast console.



This beast was removed in (supposedly) working order from KBPS radio here in Portland sometime in the last couple of years. Then it sat in the basement of the guy I bought it from, who evidently never had the time or know-how to set it up. He thought it was a tube console from the 1950?s. It is not. As near as I can tell (from reading the labels on some of the Shallco cans on the inputs) this board was probably built in 1976, potentially by the company Autogram. It is most definitely solid-state. It looks to have some decent parts inside, as well as some things I haven?t yet identified.

My goals for this monster:

Based on the way I work, I?d love to end up with 1-2 mic pres and maybe 8 channels of out-of-the-box summing. From what I?m guessing about the guts of this thing, I?m hoping that will be a reasonable proposition, and one that will allow me to make modifications while keeping this thing intact.

I'm still trying to dig up a manual and/or schematics for this board, though I have found a guide to the screw terminals: http://www.autogramcorp.com/ic-10.html

I'll use the next post to put up some photos of the guts and my dissection of a few of the modules. :grin:

Jed

This thing has a flip-top head! At the top right you can see the input modules. Most of these (18) are transformers. The black one appears to be a pre-amp module.


Here's the back side. Screw terminals, modules, transformers, monitor amps, headphone amps, power supply towards to back.


And a "holding the camera over my head" photo for good measure. Check out the giant power transformer in the far right.


A close up on channel 1.


And channel 1 from the back.



Allright, dissection time. Here's a close up of that black module from the first channel. I'm guessing that "Leightner" is the input transformer? Anybody know?


Now we have a close up one of the other 18 identical input modules. I had a hunch they were going to be transformers, and my hunch was right. I found a Triad A-67J on the inside.


Now for some of those modules along the back. I'm guess that is the output/mixing section. There are three rows as you can see. The first row has modules that are all labeled "MXA-1" (mix amp?). The second row is all labeled "LA-1" (line amp?). The third row are all more Leightners - and I'm assuming they're trannys. They're fixed to the board so I haven't tried to rip them off.


An MXA-1


An LA-1


Turns out these two are using the same PCBs, just with slightly different components.



So that's it so far. Anybody have any sense if I'm right in my guessing(s)?

I'll post more when I track down a manual/schematics.

Jed

It is beautiful.

The car collins a dream in the boyhood. For the ham radio.
I hope a photograph of the meter and a right side.

Because I wanted also to make a simple mixer, it became reference very much.

tosch http://www.n-tosch.com

score on the a67j's!

unmodified it looks like you already have a usable mixer for OTB summing. Its 10 channels of input? They must be hardwired to a stereo buss with set gain? I dont see a fader for the output?

I would get your computer hooked up to that ASAP before you do any mods at all just so you can evaluate how useful it is with your current work flow or if you can alter your flow to accomodate the console. You may find it perfect as is once you figure out its quirks, this is usually necessary for any old console, neve, api and all that crap included.

dave

Wellcome Jed, nice first post, superb console. :thumb:

chrissugar

Wellcome Tosch :grin:

Where you have been for more than two years. Great to see you again.
What did you do all this time? Any interesting projects?
For those who don't know Tosch was a member of our comunity at the "ex place". Coincidence is that a week ago I was thinking about him. :grin:


chrissugar

Thanks Wellcome Message.
I had manufactured V1-junior last year.
It looks like JLM. The small mixer called it and
S-mix tyoeVI was made. The bus compressor of the SSL is built into.



I wish to express my gratitude.
To everybody who reads my strange English

tosch

P.S.To put the photograph, it challenged. good

Hi everybody,

Thanks for making me feel welcome. I've got some more photos...but first:

unmodified it looks like you already have a usable mixer for OTB summing. Its 10 channels of input? They must be hardwired to a stereo buss with set gain? I dont see a fader for the output?

Click to expand...

I'm sure you're right. There's definitely no master fader. There definitely is a stereo buss output [as well as a "cue" output, headphone output(s) and monitor output(s)]. Between all of those things it ought to sum just fine. Assuming I can figure out which screw terminals to connect to, that is!

I would get your computer hooked up to that ASAP before you do any mods at all just so you can evaluate how useful it is with your current work flow or if you can alter your flow to accomodate the console. You may find it perfect as is once you figure out its quirks, this is usually necessary for any old console, neve, api and all that crap included.

Click to expand...

I agree completely. Creating the wiring harness(es) is going to be the number one first "mod." As this is my first console, I'm sure there's going to be a bit of a learning curve...

----

And now some more photos...

First, for Tosch, here's a photo of the VU's


And the requiste closeup. They're API Instruments VUs.


Now we have a photo of the outside of the right-hand side of the console. The top two switches are to select from "Remote Lines" and are probably wired into the pots of channels 8 and 9. This thing has a *huge* amount of switching possibilities (if you build a big enough wiring harness). I learned that the "IC" in IC-10 stands for "Instant Custom" -- highly modular and very user configurable, if you know what you're doing.

The buttons on the bottom were used to start remote devices (like cassette decks, cd's, radio "carts", etc.).




Here's a view of the right-hand side, but from the inside. From left to right, we have the monitor, cue, and headphone amps, the power supply, and the output terminals. (I just did a quick count -- taken together the input and output terminal blocks are 15 high by 19 wide - for a total of 285 screws. That's a lot of chances to - erm - screw up! :shock:


Here's a close up. The monitor amps are on the top, the cue amp is on the bottom left. The first of the two headphone amps is on the bottom right. I checked the fuses this morning. There's some values in there that appear to be wrong -- and wrong in the wrong direction -- from the values printed next to them on the metal casing. I'm going to replace those down to their stated values before I attempt to power this thing up.


And finally, the two headphone amps together, the PSU and it's tranny, the power switch (next to some relays?), and the begining of the output terminals.



Man, oh man, I am really excited about this thing! Time to do some research so I can go about building a proper wiring harness to test it out!

Jed

It occurs to me that this thing probably has a few old electrolytic caps in it that haven?t tried to take a charge in a good long while. Maybe as much as two years or more.

I happen to have a BIG (12 amp I think) Staco variac that is currently performing light duty as a dimmer for the lights in my studio. When I wired that up I decide I should wire in an outlet that would also be controlled by the variac.

As I?m thinking ahead towards powering up this baby, do you all think I need to be particularly concerned about blowing out some caps? Should I do a multi-hour or multi-day voltage ramp-up with my variac? I was reading elsewhere (http://www.groupdiy.com/index.php?topic=2363) about reforming caps but it wasn?t totally clear to me if it?s the same thing just to plug the whole device in, versus reforming an individual capacitor.

Any thoughts?

Thanks!
Jed

You'll probably be alright, I've powered up much older stuff without any suprises.

Hi! Jed

Thanks.
It became reference very much. Thank you sincerely.

You are good friend Now.

tosch

Autogram...that brings back more than a few memories! Indeed, they were the "OEM" for Rockwell/Collins audio gear soon after Rockwell bought out Collins, and began cutting product lines and doing other things that HUGE companies tend to do with their smaller acquisitions.

I've installed more than a few of the Autogram broadcast mixers. These shots (mostly scans of 35mm film contact sheets) were from a big project I did at KNTU in 1990. KNTU is the non-commercial station owned and operated by North Texas University in Denton, TX., and is part of their training facilites:

http://www.brianroth.com/projects/kntu/

As you can see there were...hmmmm....5 or 6 separate control rooms, alll with Autograms except for the Yamaha-equipped production room.

I also installed a couple of newer Autograms here in OKC. Looking through my docs/manuals, all I have are some for their AC-6 model.

EDIT/UPDATE: In my AC-6 manual, I do have the schemos for the MPA-1 mic preamp, MXA-1 mixer amp, CA-1 cue amp, HA-1 headphone amp, MA-2 monitor amp, and LA-1 line amp. However, the rest of the AC-6 internal wiring stuff is only applicable for the smaller AC-6 unit.

Autogram is alive and well...a family-owned operation in Plano, Texas:

http://www.autogramcorp.com/

I bet they still have all of the schematics and service info for that desk! They are VERY nice folks to deal with.

Bri

PS, broadcast desks never have any sort of master fader.

Wow, Brian! Thanks for the great photos. That must have been an incredible wiring job.

I emailed Autogram yesterday inquiring about schematics and manuals. I'll call them if I don't hear back soon. It's nice to be able to support a family-owned operation in this day and age.

Jed

Bri, are those 66 blocks?

As you probably know, they're meant to be used with ~22 ga. solid. I've had mixed results using those with 22 ga. stranded. It seem it's usually OK if the punches are done carefully. What's your experience with them?

Allrighty then.

I've got a manual on the way from Eddie at Autogram and some wire, xlr connects, and trs jacks coming from Redco.com. Very soon I'll be able to see what this baby is made out of.

I'm especially looking forward to the manual and the schematics therein. As I've gone over this console, the only thing that seems out of place is that one of the Mixer Amps is not installed.



See that black box in the first row? According to a block diagram on the inside of the console lid, that box should be an MXA-1 Mixer Amp. When I opened it up, however, it just has a few resistors soldered accross the connections to provide a load on the system. I'm hoping the manual will be able to shed some light on what this block is supposed to be doing...

Jed, that KNTU project probably was part of the reason that I now have grey in my beard...LOL! Being a state-run operation, the red tape was incredible.

After it was all said and done, I recall making around minimum wage for all the hours I spent there.

Never again. But, it was an adventure.

Bri

Dave, you are 100% correct. The 66 blocks (actually M-150 blocks, but the same pins) were part of the specs from "the State of Texas". The station's chief engineer was an Olde School guy who had been using those punch blocks all his life, so it was part of the spec.

However, Ma Bell used solid conductors in her system, so stranded was potentially dicey.

I've had pretty decent luck with 66 blocks along with 22G stranded wire over the years. It all began Back In The Day when I was a skinny kid who installed an MCI JH-428 desk at a local studio. MCI shipped that desk with a variant (model now forgotten) of 66 blocks for all I/O, including mic level!

I haven't used 66 blocks for a new install in MANY YEARS.

But, my olde pictures will haunt me forever LOL.


Bri

Jed, I'm glad to hear that Autogram is still the friendly company! Awww shucks...sometimes "us folks" from the southern USA areas aren't just stupid rednecks in a "red state" LOL!!!

Seriously, Autogram has a ton of respect in the radio biz, with the typical 24/7 operations and bozo DJ's pouring coffee or whatever into the gear.

Of couse, that entire radio concept is dying as Clear Channel, etc spin everything off to servers, hence no need for DJs..or Autogram mixers.

I wish the good folks in Plano, TX the best.

BTW, Jed...on-air "DJ" desks are a far cry from typical multitracking desks. Each world has their own specific requirements. Once upon a year, I was an on-air DJ at a local FM radio station while also working in the music recording biz.

Bri

I finally have an update to post! What a long time in coming, eh? (But in fairness to myself I had a few things going on this summer - got married, did a 200 mile bike ride between Portland and Seattle, attended SIX other weddings, completed an overhaul of my backyard, and now got roped into working on this election...just to name a few other projects.)

Anyway, over the last months I scrapped together enough time to build a little patch bay / breakout box to finally test this baby. About a week ago I nervously fired her up. No smoke! The meters moved!

I tested the microphone preamp: Nothing. Well, nothing except for noise that is. I tested a few of the line inputs: They're good! And they definitely impart their own sound to things!

But there is a sea of NOISE. Now, I didn't have the whole unit properly grounded when I did the test, so I'm sure this is part of the problem. (The AC in IS grounded, but I didn't attach a giant ground wire to the chassis like the manual wants me to.) But even after that I'm sure there some other things going wrong.

My gut instinct (from doing a LOT of reading around here) is that I probably have some capacitors that need switching out. Would that be the first place you all would start?

I've got the schematics but I think it's going to be a big job and a hell of a learning experience for me.

Before diving in and potentially messing this thing up, I want to start with something a little more simple/common (and hopefully easier to trouble shoot as I'm learning). So I've picked up a couple of PM1000 strips to rack up. Hopefully this will give me a good chance to get some capacitor swapping under my belt before I dive into all 9 of the line-amps in this big boy.

Naturally, the PM1000's that I grabbed have an uncommon problem (broken inductors) that there isn't a lot of info out there on. (See http://www.groupdiy.com/index.php?topic=4222.) But learning is what I'm in this for, right?!

Anyway, I just wanted to document the glacially slow progress on this old beauty and thank you all for the inital thoughts and inspiration to take on this project.

I've got the schematics...

Click to expand...

please, post!