Gotta clean up the relays...
As I started tracking down the lifter issue in the schematics it naturally led me to the Control Relay Box...that's where all the big relays are for all the transport functions. I finally put one and one together and realized that the Control Relay Box is the MM-1000 equivalent of the Control PCB that is in all the Tascam stuff I've worked on...duh...that's why they both have "control" in their names...Here's an example of one...this is from my 388. It is the larger PCB just below the transport assembly:
Here is one from a Tascam 58:
Nominally sized PCB's with quite a bit of stuff on them.
Here's the equivalent of the Control PCB on the MM-1000:
For perspective sake that's a 4U rackmount box full of electromagnetic reed type relays, like the kind that go "click-click...click-click" in your car only these ones are bigger and they go "klack!" when energized.
So I'm doing the sweetbeats thing and going through it and cleaning it up, but I really think I need to do that before I go running tape on the transport because there is evidence that it needs attention. Evidence like the fact that the lifters don't work and the capstan never shuts off. That tells me that there may be other issues and if there aren't yet there will be and I don't want to end up chasing my tail.
I'll get some pictures taken and put them up later but I've done 1 of the 8 relays so far and it didn't take long and when I got in there my conviction about my plan to take care of this first was affirmed: the contacts on the relays are really dirty. Just normal stuff for a 40-year old machine that's had some use, but I'm using DeoxIT D5 and a worn-in piece of Scotchbrite pad to shine each contact up and then hosing it down with more DeoxIT and drying with a soft cloth. In some cases I'm even taking a fine file and smoothing the contact surface because some are even a little pitted (not from rust but as a result of the aprking that occurs during normal operation). Its basically like refreshing the points in a traditional automotive ignition system, but a whole bunch of times...two contacts in the ignition system, 16 per relay on most of the relays in the Ampex. BUT, when I get done I'll have more confidence that issues are not Control Box related and hopefully I'll just be heading new issues off at the path.
Another thing I discovered is that the wiring on one of the tension resistors (which, BTW, to continue the "everything is bigger on an Ampex" theme, are resistors the size of a Coney Island Foot Long) is burnt and the slide clamps to which the wires attach are corroded:
That wiring got
hot at some time.
The advisement I have received is kind of what I figured...loose screw connections or slide clamp contacts that began to oxidize increasing resistance and heat and on and on the cycle went. So the wiring needs replaced, the clamps and contacts cleaned up and when I replace the wiring I'll be soldering the wires on rather than screwing them to the terminals.
Don't worry. This isn't going to drag on like some of my other stories where I go too deep and end up ruining something (knock on wood). That's part of what I'm enjoying about this machine is that the electronics are much more macro and the electronics being discrete and also systematically independent means there is less to kill if something goes drastically wrong. This isn't making me overconfident, but just at peace that the skills called for to do the work are in balance with me.
I loved my 58...sophisticated and relatively refined...compact and handsome looking, but I like to know how stuff works inside and out and to be able to fix it and I don't think I'm going to excel to the level of being able to troubleshoot and repair logic circuitry and the like. It puts what evm1024 does into perspective as he has a number of heavy-duty projects on his bench right now, my old 58 among them, but he has the background, knowledge and aptitude to attack those issues. So what am I trying to say? Balance. Use gear or try to acquire gear that can bring you the results you like but also gear with which you are comfortable. If that means you have a friend or a shop that you trust knows that piece of gear and can keep it going for you if you aren't into the DIY/maintenance thing, no sweat, but I mean letting some of that criteria play into what you choose to operate. I guess its like what cjacek and others have been saying for a long time, for instance, about criteria for selecting a tape machine, and being
less concerned about
which tape machine, and
more concerned about the condition of the tape machine you buy (when given more than one option to purchase).
The MM-1000 is (obviously) awkward and huge. I'm trying to figure out how I'm going to fit it in my little control booth...it'll fit, but getting it from the shop to the garage will be an operation and I need to clean it up first because once it is in there it will be
tough to move and access all its parts. I want to get it in there ASAP as it is in an unheated space now and the weather is quickly turning here in Oregon (plus the shop is now a very dirty place with the horses out back and the hay and all that), and my point is that I'll still need to work on it once it gets into the control booth but I can't just put it on the workbench in there and move it around because the MM
IS a workbench size-wise...so those are some of the drawbacks and one of the main criticisms of the MM-1000, but everything else just fits so nice with me and I encourage others to take that kind of look at what they are using or what they are seeking and look at it through that lense...what will really be the best machine to live with and use for
you because I believe that is a big part of what helps good art to happen; when you are comfortable with your canvas and brushes...when you're not distracted by a discord but rather excited and even inspired to work with the machine that is going to capture your sounds. Its just one piece of the big picture but I think it is an important one. I feel this way about both the MM-1000 and my 388, though the 388
does have a bunch of that confounded logic circuitry...