i recently picked up a mixer that does not have any schematics and there are probably none of these in north america however id like someone to look at it and give me their best guess if this was some aftermarket mod, cause it sort of looks like one to me i am the direct cause of the problem as well . as i went thru the pots with d5 i noticed two 1 watt carbon film resistors they looked homespun and were kinda flat on the pcb so i lifted them a bit and in doing so they shorted on the adjacent module so i cut power and took some pictures if anyone has any idea what the purpose of these one watts that stand out like a stop sign amongst the gaggle of quarter watt resistors that inhabit this thing.it is tlo72 based knock off of lower line trident and allen and heath system 8 I'm certain that some of you folks have seen aries 24 8 16 etc this model was the flagship there is no usable info with exception of one green band left on resistor so we know its a 5 question is 5 ohm 5k 5m> ? AND THEN start adding numbers on the fluke it ranges all over the place and settles at 2.4 meg sometime 4 .2 meg sometimes so i believe that they are useless .the only hope i have is that this is some sort of fix that was put in but any advice is appreciated as this will be the worlds largest paper weight if i dont sus it out thanks for reading I'm hoping someone will give me ideas as to what to do besides chaining my leg to it and jumpin off the santa monica pier which has already occurred to me .the last clue is it has something to do with the output of the stereo this is the master module and as i said its not difficult to see two big resistors in
terry, post: 452527, member: 50808 wrote: I recently picked up a mixer that does not have any schematics, and there are probably none of these in north america. However, I'd like someone to look at it and give me their best guess if this was some aftermarket mod, because it sort of looks like one to me.
I am the direct cause of the problem as well. As I went thru the pots with D5, I noticed two 1 watt carbon film resistors. They looked homespun and were kinda flat on the pcb, so I lifted them a bit, and in doing so, they shorted on the adjacent module. So I cut power and took some pictures. If anyone has any idea what the purpose of these one watts that stand out like a stop sign amongst the gaggle of quarter watt resistors that inhabit this thing. It is TLo72-based knock off of lower line Trident and Allen and Heath system 8. I'm certain that some of you folks have seen Aries 24 8 16 etc. This model was the flagship.
There is no usable info, with exception of one green band left on resistor so we know its a 5. Question: is it 5 ohm, 5K, 5M> ? AND THEN start adding numbers. On the fluke, it ranges all over the place and settles at 2.4 meg sometimes, 4.2 meg sometimes, so I believe that they are useless. The only hope I have is that this is some sort of fix that was put in, but any advice is appreciated, as this will be the worlds largest paper weight if i dont suss it out.
Thanks for reading. I'm hoping someone will give me ideas as to what to do besides chaining my leg to it and jumpin off the santa monica pier, which has already occurred to me. The last clue is it has something to do with the output of the stereo. This is the master module, and, as I said, it's not difficult to see two big resistors.
Yes, it looks like an after-market modification. The two 1W resistors are in the power rails to the TL072s, presumably to provide some extra local filtering.
Did the burnout of these resistors happen when you managed to short them against the adjacent circuit board, or were they like that before you did your manipulation?
There's not much information around about these consoles, but I do have an old address in London for Aries. No point in trying it now, as the building has been demolished and expensive flats put in its place. The website Vintage Mixing Consoles has an advert for the Aries Apollo, of which the Artemis was presumably a forerunner.
I look at the picture and see a lot of bad joints (some dirty, some with too much solder and flux). Someone went crasy with an iron did it ?
Once modified we need to be very carefull with those frankenstein board ;)
I put my confidence in Boswell to be of great help !
many thanks to you i see the same things going on ive looked at quite a few master channels amek ,soundcraft, studer etc indeed someone has been buggering about in there i must confess it was my fault cause i moved them clear of one another and in doing so more then likely shorted them on the other module do you have any idea what should be put in its place it is wired in a odd sort of parrallel fashion i hoping mr boswell will chime in thanks very much for your response i will do my best to clean up the mess in there hopefully more info will be advised t
fixed problem with two 47 ohm resistors still have bugs but im out of that part of the problem thanks for the inspiration
Glad you got past that hurdle. How did you arrive at the value of 47 Ohm?
old fashion kentucky windage and a bit of ohms law i dont believe those resistors are doing anything there is another issue that was not checked cause it was already detected only the right side of the stereo mix is functioning however when i go to the mono switch i get both speakers any ideas on where to look for that bug is also appreciated but many thanks again i am puzzled as to where to look for this no left side stereo gliche
Try a simple test: with the mixer set to normal stereo, feed a signal into just one channel and turn the channel's pan control all the way from one end to the other. Does the signal at the mix output go from zero to max (or vv) or does it just dip in the middle? Now switch to mono and do the same test. Report the result.
Does that mixer have a balance control on the master section?
yes there is a detent in the middle of the pan pot of each channel goes dead as soon as its panned but can hear both monitors when mono summ button is hit im wondering it the morons that did this resistor thing didnt bugger something else also master mute light is on and has no effect could it be a op amp or just a bad connection the wiring they had on there does not make sense at all to me but i committed it to memory and it is fixed in that aspect but whole left master channel down in stereo all pan pots to the left and silence hit mono button both speakers can be heard if you happen to see where the left and right feed out please gimme a clue thanks very much you guys are great no one has been more helpful
Probably the summing amplifier in the faulty master channel (L or R).
Tell us exactly which was the board you photographed and posted earlier. To give any clues about your missing output channel, we would need to see the master board, or whatever it's called in that mixer.
the photo is indeed the master board the selector for stereo monitor is the 2nd switch far right upper part of photo if you need anything at higher rez or the back of the pcb i will be happy to post it