just bought a Emulator II+ service info needed please

[lennox]

i'm very happy with it exept it needs a bit service.

2 voices are dead and 1 is distorting (sounds very loud)

i opened the lith an noticed that 4 IC's are missing they are IC 149, IC151, IC 139 and IC 134 is this normal?

if not couls someone help me with the partnumbers or better yet the IC'S  i 'm not a pro tech but not afraid to open thing up 

Thanks for helping, regards,

Alessandro

[dr.c]

Where are they ? (picture would be great !)

[lennox]

Where are they ? (picture would be great !)

Hi Dr.C

thanks for helping, i couldn't rest so i searched the archive here and on the Yahoo forum and found this mentioned in a topic....

Greetings, yes you should be missing IC chips# 134/139/149/151 (from L>R on the
very top row of the E2's digital board just below midi ins/outs).

So it seems normal missing these IC's that's a relief 

Now for the voice problems someone mentioned that reseating all IC's, connectors and cleaning them would help a lot. I'm trying to translate "reseating", does this mean pulling out from its socket, cleaning and then putting it back?

Maybe other advise for these dead voices and one is distorted (playing very loud)?

Thanks again!

did i mention i'm very happy with the Emulator???  what a machine  just located a old mac SE30. I was surprised that they call these RETRO MAC's and asking ridiculous prices  but i found a complete one for about 25 bucks 

i'm getting all the library's need the connection cable from Mac to EII though

[dr.c]

Find the faulty voices buy putting the jack plug into the separate outputs and listen.
In the inside, you will see columns of components (vertical columns) corresponding to the jacks. Each output has its column, if you look well.
Locate, on every faulty column, a component named S3528. While the machine is shut down, take this circuit awy and put it back in place, on each faulty column.
Re power, test the sound, and tell me the result.

[lennox]

Find the faulty voices buy putting the jack plug into the separate outputs and listen.
In the inside, you will see columns of components (vertical columns) corresponding to the jacks. Each output has its column, if you look well.
Locate, on every faulty column, a component named S3528. While the machine is shut down, take this circuit awy and put it back in place, on each faulty column.
Re power, test the sound, and tell me the result.

Thanks DR.C

i located the S3528 on the faulty column, 1 channel worked again (YEAH!) the other two channel 5 and 6 still have problems. Channel 5 works but plays too loud, channel 6 doesn't work but i can hear a beep tone in the distance and it changes tone when i play another key. I reseated the SSM chips as well did'nt work either, also i swapped them with work ones i know they work from another channel. Also swapped S3528 from channel that plays loud, well it stil plays loud. Channel six S3528 seems to be defect that is that putting it in a working channel stopped that one. A good S3528 in channel six doesn't do it

Any other tips are most welcome!

thanks!

[Elmbeatz]

Do the whole reseating procedure. It's painful  , but your EII will be thankful. 

[dr.c]

There are some 4051 (can be CD4051 (RCA) or MC14051 (Motorola)).
They may be in the rows or shared between two rows (5 and 6). Change the bastards, especially if they are CD4051 wich are NOT reliable. They are CHEAP (around 2$ each) and tehere are not so many.
Make a damn picture I asked you, I can pinpoint where !!!!!!

[lennox]

ok Elmbeatz, i did the reseating procedure.......... man o man what a job, i hope i do not dream about little black spiders with iron legs   

thing is, the problem remains channel 5 and 6, 5 is playing to loud and 6 does nothing..

I looked for the 4051 or MC14051 ic's, and located 3 of them..

I made a couple of foto's Dr C

From Channel 5 and 6 in different angle's










And here is one where i found the 4051.... sharp leftside only



I hope this wil clear things up, can't wait to hear all the 8 voices

Thansk again for helping!

[lennox]

oh yes, double click the foto's in the imageshack page for even larger foto's 

[dr.c]

These three damn 4051 are analog multiplexers 8 voice. One is for the gain, the other for frequency, and the last for the Q
Take them out and put them back, restart the machine and see, just like the S3528s

If not, change them. Even if its for nothing, you will NEED THEM ONE DAY.

Let me know.

Chage as well an AMD circuit (for example) from a non working channel to a working one, and see if the fault went to the other channel.

[Chaztech]

I have followed this thread at a safe distance. So pardon my butt in.
Dr C is a smart cookie and correct!
The 4051's are notorious for dying.
I see this a lot on prophet 5's and others.
this was used to scan the buttons and switches and drive cv voltages etc.
using successive approximation, time slicing,
its a multiplexer. 3 bit 8 Chanel analog In/out bidirectional.
C'mos technology that is now at end of life expectancy.
i think the very early chips had only a 12 to 15 year life span.
but latter ic's of the same number can live indefinitely.
so acquiring new ones even to have on hand would be smart for the emulators future.

[lennox]

ok i'm convinced i'm changing these 4051 and S3581 i let you know when  i did. I hope to pick them up this afternoon.. 

[dr.c]

Let us know where you can get these parts !!!!!!

[Elmbeatz]

Let us know where you can get these parts !!!!!!

YES! PLEASE!

[lennox]

i get them at www.vintageplanet.nl better bookmark this page this guys has all the parts you need, he's getting new stock all the time

Normaly i drive to him, it's a 15 minute drive to Amsterdam from my house    but i can't get off from work so he will send them to me i get them friday.

I keep you posted !!!!!