Strand Impact console

[dj41354]

I just picked up an old Strand Impact console that I'm trying to get working. I've managed at least to get it powered up (the internal power supply was defective)... but it looks like I need some help. The Video Out RCA connector sends out something that just looks like lines of static to a TV using video in.. does anyone know whats getting sent out on the video jack? Also, there's a 9pin Dsub labled "analog RGB video".. does anyone know what's getting sent on that? Is there an old school monitor I can buy on ebay that will work with this, or a converter of some type that will let me use a modern 15pin VGA monitor?
Thanks in advance for your help!

 

[icewolf08]

You probably need a CGA monitor to work with the console. There are a few places where you can get them and eBay is probably one of them. I am not sure if anyone make a CGA to VGA adapter, but if you could find one, that would probably work as well.

 

[derekleffew]

See the thread ETC Microvision Monitor help please.

 

[pathway]

I'm pretty sure the 9-pin D-sub outputs CGA or EGA video, neither of which is compatible with VGA but a converter may be obtainable. I used NEC MultiSync monitors on the Impacts I sold since they could handle anything that was a video standard in those days (late 80s-early 90s). You might be able to find one on eBay as icewolf08 suggested. Make sure it has the 9-pin connector as later MultiSyncs were VGA (15-pin) compatible and they won't work.

 

[dj41354]

Well, I've managed to get my hands on an original NEC Multisync 9pin monitor. I haven't actually tried it yet (I just got it) but I'm not convinced that this monitor connects straight through (pin1 to pin1 ect.) to the 9pin "analog rgb" console connector... was there a custom cable involved? or adapter or a pin swapping cable? The only reason I say this is that I scoped the signals coming out of the console and it looks like the rgb is on pins 1,2 & 3 (top row 3 right most pins looking into the female) but the CGA standard (which I believe the NEC Multisync is set up for) calls out for pins 1 & 2 to be ground, and pins 3,4 & 5 to be rgb... I'm still looking into this but I think I'm missing something.

As far as the monitor's settings go, I assume the TTL/ANALOG switch needs to be set to analog, but were any of the dip switch settings required? I'm still looking for info on-line, but from what I've read the monitor is pretty good about figuring out what's getting sent to it. I'm guessing the dip switches are for EGA (TTL) and not functional in analog mode.

Thanks again for your help!

 

[dj41354]

Got it. It was as straightfoward as you all said. The NEC Multisync was the key... the cable was simply a straight through pin1 to pin1 connected.

I've been working with a couple of guys designing a new LED fixture for the past year, so I'm pretty well versed in the technical aspects of DMX, but I've never used a DMX console before. I bought this console because it was really inexpensive ($20), and I wanted a pro quality DMX source instrument to test the lights with. Assuming it all works ok (so far everything looks good) is this a good DMX console?

One of my buddies picked up an Elation DMX Programmer for $100 a while back, and it seemed to have some subtle issues. For example when you 1st started adjusting a new slider, the DMX didn't respond instantly, but then if you adjusted that one again, it was instantaneous... whenever something weird happened with the DMX I was always wondering if it was the new light firmware, or the DMX console... anyway that's why I started looking for a pro quality instrument that I could get used for short $.

I think this is gonna be fun.....

 

[dj41354]

I can't seem to figure out how to make the Strand Impact output it's DMX on the 2nd set of universe wires.. is this possible? Also, so far I've only been able to make the console adjust brightness values by percent, as in 50%. As a result brightness changes are noticeably steppy on my LED fixture at low bsettings. It seems like I should be able to make it adjust using the native DMX 8bit values, showing the HEX values on the display monitor. It knows the full brightness setting is "FF" which is the HEX representation of all 8bits on. Is it possible to set the console up so that the encoder wheel gives 255 (00-FF) brightness adjustments? Thanks again for all your help.

 

[derekleffew]

... Is it possible to set the console up so that the encoder wheel gives 255 (00-FF) brightness adjustments?

Not possible. Still rare today, and certainly not with a console of that vintage (1986-1990). "FF" doesn't actually mean 255; it's merely a two-character representation of "100%"--most consoles use "FL". The Kliegl Performer (of which the Impact is a derivative) used FF for full even though its output was 0-10Vdc analog and predated DMX512 by several years. Although the Impact outputs 256 discreet values via DMX, input is limited to 0-100%. The console calculates fades in 8-bit values however. See also the thread percent vs. dmx value.

As for the LEDs being noticeably "steppy," that's more in the fixtures than in the console. Better fixtures have better smoothing algorithms.

Regarding "how to make the Strand Impact output it's DMX on the 2nd set of universe wires", do you mean on the second, if existing, DMX output jack, or on pins 4&5 of the only DMX output? I'm guessing the theoretical maximum of 768 dimmers is only achievable by using 4 outputs of AMX192.

The Strand Archive - Impact

 

[dj41354]

Nice photo.. I really like the old school look of this console. I'm using the Impact as a test station to test a new LED fixture that some buddys and I have designed. The fixture accepts a 5pin DMX connector and can be set to decode DMX on pins 4&5 (this is what I was referring to when I said "universe 2"). It's this feature that I'd like to test using the console. Is it possible to get the Impact to send it's DMX on pins 4&5? I'd want to be able to switch it back to pins 2&3 so I can go back-and-forth between testing universe "1" and "2" as needed.

I just checked the back of the console.. it has two 5pin DMX output connectors called "DMX-1" and "DMX-2"... what does that mean? Looking inside the case, both DMX connectors have all 5 wires connected to the motherboard, and there are 3 dual UART IC's (SCN2681's) populated next to the connectors.

As always.. thank you for your help!

 

[starksk]

Nice photo.. I really like the old school look of this console. I'm using the Impact as a test station to test a new LED fixture that some buddys and I have designed. The fixture accepts a 5pin DMX connector and can be set to decode DMX on pins 4&5 (this is what I was referring to when I said "universe 2"). It's this feature that I'd like to test using the console. Is it possible to get the Impact to send it's DMX on pins 4&5? I'd want to be able to switch it back to pins 2&3 so I can go back-and-forth between testing universe "1" and "2" as needed.

I just checked the back of the console.. it has two 5pin DMX output connectors called "DMX-1" and "DMX-2"... what does that mean? Looking inside the case, both DMX connectors have all 5 wires connected to the motherboard, and there are 3 dual UART IC's (SCN2681's) populated next to the connectors.

As always.. thank you for your help!

I find it interesting that your fixture design is using pins 4&5 for a second universe of DMX. That is not within the spec DMX and I can virtually guarantee you that no console that is adhearing to the DMX Specification will ever send a second universe of DMX on those unused pins. In fact in most places, those pins aren't even connected to anything.

As for how to do it, (and keep in mind this is speculation not having physically touched this specific console) I would say that you would need to move the wires that are connected on pins 2 and 3 from DMX-2 to pins 4 and 5 on DMX-1. That would mean that both outputs of data are connected to a single connector. Depending on how the grounding/common is referenced, you may also need to move pin 1 from the DMX-2 and join it with pin 1 on DMX-1. That also may cause additional issue and it may be best to remove that reference altogether on the motherboard side.

Will it work? Maybe. Is it a good idea? For your own testing and edification, possibly. For use in the real world, I would stick to the DMX specification.

Good Luck!

________________

~Kirk

 

[derekleffew]

... I just checked the back of the console.. it has two 5pin DMX output connectors called "DMX-1" and "DMX-2"... what does that mean?

Most likely, "DMX-1" is dimmers 1-512 and "DMX-2" is dimmers 513-768. More modern consoles allow the user to specify which dimmers appear on which output port, and even assign both the same as a poor man's opto-splitter.

Might I suggest that if you're developing fixtures, generating DMX from a device such as Goddard Design's Lil'DMXter would be more prudent than a circa 1989 console?

I find it interesting that your fixture design is using pins 4&5 for a second universe of DMX. That is not within the spec DMX and I can virtually guarantee you that no console that is adhearing to the DMX Specification will ever send a second universe of DMX on those unused pins. ...

Some Avolites consoles (I'm certain the original Pearl and suspect others) did this. To access universes 2 or 4, a special break-out assembly was supplied:

Data Products Cables & Adaptors: Universe Saver Adapter Set | Lex Products

Although you may still be correct on the "adhering to the DMX Specification" part. I once had a situation where an ETC Response opto-splitter would not distribute data from a Pearl, and it had nothing to do with the pinout. Swapping the opto with another manufacturer's solved the problem, and the Response had no issues with DMX from the HogII.

 

[starksk]

...Some Avolites consoles (I'm certain the original Pearl and suspect others) did this. To access universes 2 or 4, a special break-out assembly was supplied:
...
Although you may still be correct on the "adhering to the DMX Specification" part. I once had a situation where an ETC Response opto-splitter would not distribute data from a Pearl, and it had nothing to do with the pinout. Swapping the opto with another manufacturer's solved the problem, and the Response had no issues with DMX from the HogII.

Learn something new everyday!

_______________

~Kirk