Ampex MM-1000 Story...

  • Thread starter Thread starter sweetbeats
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Nice units. I'd solder them just to make good contacts.

I see they are originally made in Joliet, Illinois

There is a large prison there. Maybe the "boys" there made them!

They were always looking to make contacts!!!
 
I'm leanin' toward using the solderless connectors big-time...starting working on swapping out the play relay tonight and the existing wires are just too short to really make this work if I try and resolder the wires. I don't think there will be a reliability issue, and frankly being able to pull individual wires for troubleshooting could be really handy.
 
I love my MM-1000...quirks and all. I can't wait to partner it with the JH-416. The Ampex has been getting royal treatment over the last couple years getting refurbished here. I have everything to convert it to 2" 16-track as well.

Yep...all AC motors and no tension "logic" whatsoever. Good old tension resistors the size of hot dogs...grab that tape and drag it through, heheh.

It DOES have 24V relays though.

It's a good match for me and my technical skills. IC logic scares me.
 
johnkavan said:
I love my MM-1000...quirks and all. I can't wait to partner it with the JH-416. The Ampex has been getting royal treatment over the last couple years getting refurbished here. I have everything to convert it to 2" 16-track as well.

Yep...all AC motors and no tension "logic" whatsoever. Good old tension resistors the size of hot dogs...grab that tape and drag it through, heheh.

It DOES have 24V relays though.

It's a good match for me and my technical skills. IC logic scares me.
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jahnkavan, that's wierd...why did you copy and paste my post from the MCI Recording forum?
 
You guys...kooks...every last one of ya. :)

So I went ahead and ordered some solderless connectors. 100 each of the 18~22AWG and 16~14AWG in the 0.205" female spade disconnect. $14 shipped for all of them and I made sure they were copper core and not tin or aluminum.
 
Well, I replaced relay K6 which is the PLAY relay. Didn't fix my intermittent play problem, BUT I didn't make the problem any worse. So surely I didn't hurt anything by putting the new relay in.

Here it is...the one with the solderless connectors. The original relay is perched on the relay box chassis to the upper right. Now I get to figure out what to do with it. Its not like an old cap or solid state relay...pitch 'em...this thing is a small electro-mechanical machine. Er...maybe not so small.

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I also shot a short video of the play problem in hopes of getting some assistance from the folks over at the recordist.com Ampex List. No sense in not sharing it here...get to hear all the lovely racket my Ampex makes and see the pretty-pretty lights.

YouTube

Replacing the relay is the first time I've messed with the MM-1000 for a little bit. You know you're a good fit with a machine when you just like operating it even if it isn't working right... :D
 
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Could the relay you replaced be feeding another of those relays you have not yet replaced and which may be misbehaving and continuing the play problem you are experiencing?
 
Sorry I can't advise on the problem, but what a treat getting to see that massive baddy in any kind of operation. Those buttons are huge! And the noises, lord! :D
 
GCalo said:
Could the relay you replaced be feeding another of those relays you have not yet replaced and which may be misbehaving and continuing the play problem you are experiencing?
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I'll double-check, Greg...good suggestion, though I think in the end it is an issue with the input to the relay...something between the control panel and the relay box.
 
briank said:
Sorry I can't advise on the problem, but what a treat getting to see that massive baddy in any kind of operation. Those buttons are huge! And the noises, lord! :D
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Brian...yeah...you get why I like this machine...I had a buddy here today that is a mechanic by trade...a very good one, but he also is one of the FOH engineers at our church so he's got some audio background. I ran the transport through its paces to show the pretty lights and to hear the noises and he got it too.

It is a "crude" transport by today's standards but its just got incomparably huge gonads for a tape machine.

I think I posted up about this a couple years ago but I found the same buttons in an elevator once...same manufacturer for sure.

I'll get it working. It wants to work.

While we're talking video of machines you oughta put up some video of your 1" MCI machine...I for one would LOVE to see that.
 
I've spent some more time with the relay box schematic. I re-read some of the theory of operation...its been a long while since I've looked at that and that is a really handy road map now that things are sinking in with how the relay box and the relays and associated components work. There are actually two play relays...the one I replaced, K6, is the one that actually powers the reel motors (through the tension resistors) as well as the capstan idler solenoid in PLAY mode. I wasn't having trouble with those before. It took me a little bit to figure it out here but K6's coil gets powered through K4. K6 is the second play relay. When the PLAY button is pushed on the control panel +24V comes over pin 5 on J2 on the relay box. K4 closes and then recieves holding voltage through terminals 3 and 4 of the STOP relay K3. If the supply reel is in a stopped state then the motion sensor assembly passes +24V to pin 19 on J2 of the control box. That goes to terminal
6 on K4 which is latched to terminal 7 at this point...*boom* K6 closes and everybody jumps into action PLUS the ever-present +24V on terminal 6 of K6 is now latched to terminal 7 which feeds back through terminals 6 and 7 of K4 to provide holding voltage to the coil of K6, because once the transport starts moving +24V is no longer present on
pin 19 of J2.

A new relay is wired in for K4. I just need to mount it to the box, and plug the cables up and test it out.

Just looking at the original K4 relay I pulled out I'm thinking, at the very least, it wasn't helping...they reeds aren't uniform and that could effect certain contacts not latching up readily, especially if the contacts are dirty, and dirty contacts beget dirtier contacts.

I'll know in a bit.
 
Well THAT'LL be fun...

Now it doesn't latch into PLAY...so holding voltage isn't getting through, at least that's my assumption. Good news is that as long as you hold the PLAY button it works great and jumps into PLAY mode every time all pronto-like...no delay.

The contacts in the old relay don't look bad but they are ones that I tried to clean up and, again, I was told that wouldn't work. I think it didn't.

NOW...why is it not latching up...[mumblemumble-tinkertinker]
 
Okay...nevermind. Still delaying at times only now there is the added fun of the PLAY mode not latching up. And now I'm confused too because according to the schematic, when you press the PLAY button which delivers +24V to terminal 2 of K4 (energizing the coil) it appears that that ALSO energizes K3, the STOP relay and breaks what I thought was the source of holding current for K4, which, if not held, breaks the source of holding current for K6 also.

I can manually actuate K4 and it works fine...by manually actuating K4 I am delivering holding current from terminal 5 of K3...so by virtue of that I am under the assumption that the wiring is correct, but somehow the +24V from the PLAY button isn't doing the trick and I'm going to need to go deeper into the schematic to figure out how its supposed to work because K4 can't get held closed the way I thought it was supposed to get held according to the schematic as well as how it is actually wired.

I'm going to read more of the theory of operation section.

Hm...the other thing is that when I press PLAY and it delays there is definitely a relay actuating. Always has been. I can remember that...hitting PLAY, no action but the STOP lamp goes out and there is a nice *KLAK*...I can remember that if I hit STOP at that point I could hear a relay releasing. I now know that was K4. It was getting held but there wasn't enough juice coming from the PLAY button to energize the coil of K6 maybe...through terminals 6 and 7 of K4. Now I see it...there is a REC/STOP DELAY relay K9 with a 100uF cap in there...don't quite get what that does or how it does it yet but I believe that fills the gap to initiate holding current while the PLAY button is pressed until you release it and then the +24V through terminals 4 and 5 of K3 takes over (through terminals 6 and 7 of K4 to terminals 6 and 7 of K6 to the coil input terminal 2).

Theory of operation...and a friend...I need a friend to hit PLAY while I measure at the relay box with the DMM...can't reach PLAY from the back of the machine...when was the last time you could say that about YOUR tape machine? :o
 
sweetbeats said:
I need a friend to hit PLAY while I measure at the relay box with the DMM...can't reach PLAY from the back of the machine...when was the last time you could say that about YOUR tape machine? :o
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Touche, sir! :D Now granted, I've performed the decidedly 2-man job of trimming power rails and calibrating meters on my console (trim pots are behind console, meters are read from front of console...urrr) all by my lonesome, that's tons of fun, let me tell ya :D

Boy Cory, you've mentioned in the past how you didn't relish dealing with control logic issues like I did with the MCI machine, but reading your last two posts gave me some transport control flashbacks alright :P In your case it's looking at voltages through relays, in mine it was probing IC pins. I know squat about Ampex transports, I wish I could help advise there! It's too bad it doesn't seem to be something simple like dirty contacts, I know firsthand how oxidation can cause gremlins.


While we're talking video of machines you oughta put up some video of your 1" MCI machine...I for one would LOVE to see that.
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Asketh and ye shall receiveth, I brought my crappy point and shoot with me to a playback session yesterday for ya, mosey over to my MCI JH-636 Story thread for a looksee...
 
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