E-mu Emulator Sampler User Forum for the EIII EII EI and EIII XP

Hello together and first of all thumbs up for this amazing forum and knowledge base !

Please excuse my english skills - I hope you'll understand me :)

I have an Emulator II+ for two years now - it worked without any problems but since yesterday it's not working anymore.
When I turn it on it loads from every disk I insert but after loading there is no sound anymore - I made a little video to show you:

https://www.youtube.com/watch?v=lEXPegb8xMU#action=share


What I noticed: In the working days of my Emulator II+ after turning it on I always had a tone like a sinus coming from very low to very high - then the disk started loading and this tone was gone.... Now when I turn on the Emulator I get this "resonant tick sounds" as you can hear on the video... they are in sync with the floppy loading sound .

I read all topics in the Emulator II tech tips  and hoped someone else had the same problem in the past - but I didn t find something like that.

I also checked all voltages of my power supply and they are all okay ! Also I found a topic where a guy with this startup sweep sound replaced IC86 - I also tried that but it didnt work for me.

Just a last information - when I turn around the main volume knob I can hear a little bit corrosion noise in my speakers - so this circuit should work.

Hope everybody could understand me :) Thank you for your help everybody (y)

all the best
Steve

"ng it on I always had a tone like a sinus coming from very low to very high - "
You mean in frequency ?

Okay, stop messing by echanging chips "out of the blue", just loke that...

What was that IC86 ?

Did you change the startup diskette ? Shut the machine down, start up and put a new diskette.

Do this BEFORE, and then, tell me what is going on.

Cheers

Hey Dr.C,

thank you very much for your reply !

I tried more the 10 different startup diskettes right now - still the same... no sound after loading.

when I turn on the machine the display says "Emulator II Boot in progress" - then I insert a disc and get the message "Software Rev 3.1" and "this will take a while" - then it loads the disc - when it is ready I can choose the presets I've loaded the usual way but there is no sound coming out of the Emulator.

The sinus tone I meant could be heard on every start of the Emulator in the past before it quit working - it sounded like a filter sweep starting at a very low frequency and coming up with a little bit of resonance. This has gone since the emulator isn't working anymore - now there are only this "click-sounds" as you can hear on the video I posted.

the IC86 thing:

there was a thread here in this forum where a guy also had this startup filter sweep sound and tried to find a reason for it and fix it - the solution was to change IC86 - so I also tried to replace it with another IC (same type) - but that didn't solve my problem !
This was the thread: http://eiiiforum.com/index.php?topic=2775.0

any ideas what I could do next ?

all the best
steve

Wonderfull....

What type is EXACTLY this f... IC86 ?   Banana78, 74LS447, Gizmo 475 ?

IC86 is CD74HCT138E (RCA H 632)

after replacing and trying the new one I replaced the old one again - so everything is like it was again.

Hi,
I tried to fnd the page of the schematics involving this circuit. I have a good idea of what it can be, but I'd like to check, to be sure. Would you have it ?

Please, don not imagine that I would think you are an idiot, but did you try to :

a) - Check the separate outputs and not only the main,
b) - Chek by Master/Special/??? if the outputs are not disabled

Please do, even if it seems stupid, but you will be sure about 100000 % that the machine is bad.

Hey Dr. C,

I checked that - but also the solo outs are not working ! I also checked in the menu that they are not disabled !

so I also checked now if its possible to sample... connected a synth to the sample input of the Emulator and played along but the Emulatur VU doesnt react (also changed the input gain of the Emulator to max) .... the machine doesnt get an input signal.

all the best
steve

Well done, for the checking.

I think I know what it is, but I need the diagram sheets. I have to dig in my archives. I'll let you know ASAP

Still looking for this damn service manual. Do you have it ? If yes, can you post it somewhere ?

You mean the EII service manual?

is it not here? schematics & service manual

http://www.theemus.com/documentation.html

I found it, it was in one of my disks... Gimme a minute to look...

Okay,

As far as I can see, IC86 is a S3528 circuit, located page 7-42, Input analog, and not a :

IC86 is CD74HCT138E (RCA H 632)

I have to look further....

Look at page 7-39. There is a DAC AD7524, IC63.

This circuit distributes a signal to three 4051 wich are analog multiplexers.
Each of them are controling the filters.
One is controling the volume output of the VCA's, so if its dead, = no sound !
Look at the inputs (COM Pin 3) if there is a signal coming. If not, look at the output of IC44 (TL084, Pin 7) if there is a signal. If not; I would say thet the AD7524 is dead.Still, look at the adress inputs of the AD7524 IC63, if you get someting.
Look as well at the adress inputs of the 4051's
I bert your problem is there.

You said you have checked the PSU, uh ?  ;D

wow, lots of good information for me ! thank you sooo much man !

so what can I do ? replace them with new ICs ? I dont have this types... wondering where to buy them but I will check ...
how can I check if a signal is coming to com pin3 or ic44 pin7 ? what signal should be there ? can I check that with a multimeter ?

yeah I checked the psu... all voltages are correct - I will check again tomorrow and post the exact voltages here.

Don't mess around by changing circuits around like a moron ! You need an osilloscope !
The 4051's have each 8 channels, one of the is foe the VCA's (x8), another for the filter frequencies, the last, for the "Q".
Even if they are the same, you cannot exchange the "just like that", because you will decalibrate the machine !

Where are you located ?

Hey there,

Here are the voltages of my power supply:

Pin 1 Red 14,5 Volt
Pin 2 Yellow 5 Volt
Pin 3 Yellow 5 Volt
Pin 4 Green 0 Volt
Pin 5 Green 0 Volt
Pin 6 Blue 0 Volt
Pin 7 Orange 11,7 Volt
Pin 8 Black -14,6 Volt

all the best
steve

Where are you ?

Dr. C !!!!
You are absolutely my man !
The Emulator is working again - it was that fucking IC63 ! Bought a new one and replaced it and now everything is working again...
I m so happy - thank you so much man !

 all the best
steve

Happy you are happy, but I'm not sure you are out of your problems.

W'ell see.

Cheers
Dr.C

Your message was indeed a bad joke !   ;D

Where are you located ? You are going to have other problems, probably.

If you toggle several times the front panel button from to "Sample" and non "Sample", do you hear a "thump" in the audio output every time you change this status ?
If yes, this means you have an offset voltage problem, wich is solved by adjusting it thru the variable resistor near the converter. IT HAS TO BE DONE !
If its okay, don't touch it !, as we say, "if it works, don't fix it", keep your damn hands off this machine (the inside, I mean).
If it does it, DON'T DO ANYTHING EITHER, just send me a picture, macro if possible, beautifull and clear, of the surroundings of this converter and pot (a square of five inches picture would be okay).
If you do anything without my permission or instructions and kill the machine, don't come at me, just die, I won't move, even a finger for you !

Cheers
Dr.C

what is that converter you are talking about ? where is it located ?

Its the damn AD7524 !!!!

very interested post with the three 4051 explanation  :o


I have the some problem. No output sounds from everywhere. Since i have change to a new a PSU.


I will change soon the AD

Thank you

Damn, you are a new guy in the loop ?
I tought at first it was the same machine !

Stop changing thins like that ! Is your PSU an original one ? With the same voltages

Yes, it was an original , from europe.

No it's not the same oldish PSU,

Mine doesn't have the orange 11,7V.  the serial is N°1086 EII.

a photo before i had changed the psu to a mean well witch i've set the good 5V output

Again,

That's ok now! I've checked thé voltage on filters IC and AD ic ; There e are all right!

I've never check an IC before with à multimeter Dr.c ... Thank you for the knowledge.

After some IC checked i've found that VR2 on analog board doesn't brought 15v as specify on schematics.

It was à bad shrink on 15V meanwell. Now it is fine!

Greats

Fells good...   ;D

Tip top! :)

Dear all , just wanted to resurrect the thread to tell that it helped me diagnose and solve the same problem i had with my Emu, i tested the AD7524 (IC 63) and some measurement were at 0 so i replaced it and resurrected the machine ! THANKS A LOT !!!