Audionics of Oregon Space & Image Composer

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bmnquad

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Joined
Jul 22, 2013
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12
Hello all, stumbled upon this page while researching a piece of equipment acquired from a storage locker. I have no means of testing it and one of the wires that is plugged into it is broken and doesn't have an end to it. I am looking to list on Ebay for fair value but because of its scarcity I don't really know what that value is or if I should get it restored prior to trying to sell it. Any advice is appreciated. Thanks.
 

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What wire is broken? Is it the grey cable coming out of "Accessory Interface"? Also RB output RCA jack is pulled partially out, might have a broken connection. This is the kind of thing I like to try and restore. Post a link when it is listed, I'm curious. No idea of the value unless it is known to be working. Maybe a picture with the top lid off that would show interested people that there is a non-rusty circuit board inside?
 
yes, the Accessory interface cable just ends in bare wires. pics of the interior, looks clean.
 

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It figures that the remote control was cut off (cut cable from "Accessory Interface" jack), it would have added to buyer interest in the auction.
I was actually the one who reached out to you through Ebay about seeing the unit in person. Congrats on the apparent sale of the unit!
 
It hasn't sold, we just ended the listing until we could get more information. We had 6 messages in an hour regarding the item and had no idea what to tell people. My brother also has the item at his house right now and has some paranoia about people coming to his house because of virus transmission concerns.
 
I thought the point of an auction was to let demand for an item set the price. But I agree, if one does not know how to answer questions about the item, it might be best to do more research. Both to avoid misrepresentation to a potential buyer, and also share enough information to attract potential bidders.
I wonder, if there is no way to test the thing, does that mean you have no DVD/CD player nor 4 or 5.1 audio system?

Edit: I just realized, if the wired remote cable is cut and ends in bare wires, please don't let them touch when powering it up! There might be some connections there where a short could cause serious damage!
 
It hasn't sold, we just ended the listing until we could get more information. We had 6 messages in an hour regarding the item and had no idea what to tell people.

Thanks for the feedback. I recently noticed it back up for auction.

I wonder, if there is no way to test the thing, does that mean you have no DVD/CD player nor 4 or 5.1 audio system?

It could be tested with just a stereo CD player and stereo inputs on a receiver: it would be a bit slow, but allow for cursory testing of surround sound synthesizing of stereo sources in both SQ and "stereo enhance" modes by testing two pairs of outputs at a time. Watching the front display LEDs could also give an indication about whether it's sending signals to the different output directions, although no guarantee that the actual output is clean.

Best of luck on the auction!
 
I have one of these units. Bought it in 1979. It hasn't been used for some time, and I think it needs to be recapped. Last time I did use it, one channel was noisy. How economically can it be recapped, or should I sell it and get a Surround Master?
 
I have one of these units. Bought it in 1979. It hasn't been used for some time, and I think it needs to be recapped. Last time I did use it, one channel was noisy. How economically can it be recapped, or should I sell it and get a Surround Master?

There are a lot of capacitors in the photos but I only count a dozen electrolytics (six in each photo), and they are the ones that usually go bad with age. The others look like film caps, and they last much longer. Half of those electrolytics are in the power supply (the bigger ones), but the smaller ones are very cheap.

I would find someone to replace those 12 capacitors and any other electrolytics that might be hiding in there. You are probably aren't looking at a lot of money for the caps, so you might be able to can find a local hobbyist to do the work. If you were local, I would do it for you for a case of beer … but not that Yank stuff.
 
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There are a lot of capacitors in the photos but I only count a dozen electrolytics (six in each photo), and they are the ones that usually go bad with age. The others look like film caps, and they last much longer. Half of those electrolytics are in the power supply (the bigger ones), but the smaller ones are very cheap.

I would find someone to replace those 12 capacitors and any other electrolytics that might be hiding in there. You are probably aren't looking at a lot of money for the caps, so you might be able to can find a local hobbyist to do the work. If you were local, I would do it for you for a case of beer.
True, you're a bit of a schlep from me. I don't have the schematic, and I think I'd need that so they'd know what values the capacitors are. I'd need to invest in that repair, plus some contact cleaner to get the controls back in shape.
 
True, you're a bit of a schlep from me. I don't have the schematic, and I think I'd need that so they'd know what values the capacitors are. I'd need to invest in that repair, plus some contact cleaner to get the controls back in shape.

The cap values are printed on them. A schematic is nice to have, but not necessary for this repair. If you were looking to modify it for some reason, a schematic would be helpful, but part for part is a pretty simple gig.
 
True, you're a bit of a schlep from me. I don't have the schematic, and I think I'd need that so they'd know what values the capacitors are. I'd need to invest in that repair, plus some contact cleaner to get the controls back in shape.
Schematics can be found here Audionics of Oregon - Space & Image Composer Schematics and here Audionics of Oregon Space & Image Composer - Info & History Over the years I replaced all the electrolytic coupling capacitors with film types.
 
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The cap values are printed on them. A schematic is nice to have, but not necessary for this repair. If you were looking to modify it for some reason, a schematic would be helpful, but part for part is a pretty simple gig.
True enough, the cap values are printed on each of them. The Schematics can be a bit confusing, I've found some discrepancies. The Schematic shows the original National Tate chips, I assumed that they were pin for pin the same as the replacements however the National LM1852 has more pins than the RA402, don't know if everything else matches up.
 
The above unit has arrived today, thanks to who I assume is bmnquad accepting my offer. I took the cover off, transformer still solidly in place, dusted with compressed air, cleaned front pots(not internal ones yet), rca jacks, buttons. I turned it on, the light came on, I connected my phone and played an SQ test tone and all of the LEDs work, so I just turned it back off, I didnt connect it to my amp to test the sound yet(will post when I do) I still want to clean it some more before connecting it to my system. The chips that I can see are Texas instruments, the serial number in the photos on the original post of this thread, could anyone tell if this unit has exar or national semiconductor chips?
20200917_131004.jpg
 
The op-amps TL074 are made by Texas Instruments. The DES chips output chips are on the lower right looking from the front of the unit with the top off. My unit with the Exar chips have heat sinks glued to them so you can't see the number. My unit with the national chips the chip number and National Semiconductor are clearly viable. The DES detector chip is above the output chips (National LM1862, has18 pins). The Exar chip has less pins and likely has a heat sink glued to the top of it.
 
Well, I lubricated the internal pots, reset them using the red paint marks, connected to my system and some clean sound came out, but it only came from the rear and seemed mono, all outputs work in 4ch discrete. It was canceling out the front vocals extremely well, when I move the main balance I hear front left or front right, stage balances do nothing at all, when I play a corner-only SQ tone comes out equal mono in rear. Also the sound cuts out if I poke anywhere near the front right area of the circuit board as if there is a bad solder connection or shorting somewhere and piece of brown tape from over where the LED display ribbon connects to a blue rectangle box on the board was detached, leaving some residue/gunk. I bought it with the expectation of probably being completely dead for the spare tate chips which, thanks to knowledge of QQrs able to identify that both this unit and my 101a are exar. Hearing the rear channels even in mono is such a tease, it could still be a karaoke machine at this point in its present state(not that I would ever actually subject it to that) the LEDs are still decoding all channels perfectly and are fun to watch. I would like to try and fix it, even if the Tate chips end up being no good, maybe I could turn it into an interesting Frankenstein project some day. I do have a couple questions: Does the detector chip stay on all the time in order to drive the LED display and what is the brown tape/gunk?
 
Well, I lubricated the internal pots, reset them using the red paint marks, connected to my system and some clean sound came out, but it only came from the rear and seemed mono, all outputs work in 4ch discrete. It was canceling out the front vocals extremely well, when I move the main balance I hear front left or front right, stage balances do nothing at all, when I play a corner-only SQ tone comes out equal mono in rear. Also the sound cuts out if I poke anywhere near the front right area of the circuit board as if there is a bad solder connection or shorting somewhere and piece of brown tape from over where the LED display ribbon connects to a blue rectangle box on the board was detached, leaving some residue/gunk. I bought it with the expectation of probably being completely dead for the spare tate chips which, thanks to knowledge of QQrs able to identify that both this unit and my 101a are exar. Hearing the rear channels even in mono is such a tease, it could still be a karaoke machine at this point in its present state(not that I would ever actually subject it to that) the LEDs are still decoding all channels perfectly and are fun to watch. I would like to try and fix it, even if the Tate chips end up being no good, maybe I could turn it into an interesting Frankenstein project some day. I do have a couple questions: Does the detector chip stay on all the time in order to drive the LED display and what is the brown tape/gunk?
First I wouldn't of touched the separation pots at all, if they are not moved they shouldn't need lubrication. Cleaning/lubricating the other pots should be OK. If the stage balance controls do nothing maybe the jumper plug is set for external control. The brown sticky residue might be from a bad coupling capacitor, one of mine had the end partially blown off. Based on that experience all coupling capacitors should be replaced. The detector chip is always on, the display has it's own driver circuit to light the display. The LEDs decoding the signals is a good sign. The display has a blue DIP plug on the end of the ribbon cable that plugs into the main board. Make sure the solo null switch is off or it will cancel out the vocals. Do you have the operation manual? If you have a bad coupling capacitor you will have either a dead channel or an output that's just not working correctly depending on which capacitor(s) are bad.
 
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