looking for api 544 input module docs

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plumsolly

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Joined
Nov 3, 2007
Messages
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Location
Denver, Colorado
Hey, I'm looking for api 544 input module schematics or any api 1608 related schematics (I already found a block diagram at Evergreen College's site) My email is plumsolly(at)gmail.com thanks, Ben
 
plumsolly said:
Hey, I'm looking for api 544 input module schematics or any api 1608 related schematics (I already found a block diagram at Evergreen College's site) My email is plumsolly(at)gmail.com thanks, Ben
I know you meant "1604". I'm sure the world will never see and 1608 documents, for good reason I assume too.

Here's a sendspace link for an input module. skiz link

It's a kinda big file.

I have 2 544 modules from a friend to repair. His are from a 1979 early Datatronix 1604. The interesting thing is that his PCB's are identical to mine. My schematic is actually for a 528 module. So, they are all the same. API just populated the boards a little differently and used different face-plates. Mostly switches for busing and whatnot.

Cheers, Jeff
 
PATAPETER said:
boys , there's a missing cap (C 25 ) in that schematic , i have the module and a later revision of the schematics and there's an add of C25 in the first 2520. As equal in the second 2520 there's C 19 .From + input to audio comm.
cheers
pedro.
Well, I can see a C25 on the first 2520. Has the upload been changed since your post Patapeter?
 
Ohhhh...... Yes......I zoomed and i can see it now. I have the schm for the 528 module and it seems to be a little bit earlier , And there's no C 25..... Sorry folks . False alarm.
Regards
Pedro.
 
Reviewing this schema, I don't see how the 2nd DOA gets its input. Would anyone mind advising me on this? Thanks.
input.jpg
 
Follow the feed for the filters up and over to the right. It goes thru jumper wire points L that are circled. Then up and over to the card edge connector #15 which is the fader wiper and is labeled "Pin 15 Fader Out".

Cheers, Jeff
 
Wait a min... so this schema also kinda showing what the card connector looks like?

For example All the stuff underlined and in brackets: |______________________|

Thats a physical representation of the pcb slots and pins?
inputedgeconnector.jpg

 
Yes, correct-o-mundo boji. 2 PCB's sandwiched with standoffs. One card has 18 gold finger connectors for 18 pin card edge connector. The other PCB has a 10 pin and a 15 pin.

The letters and numbers that are inside of large circles are jumper wire connectors that go from PCB to PCB.
 
Man how easy is that!

Thanks Jeff, that really cleared up some confusion!
Here's my transcription so far...

errata:
Title "560" should be 536
Not sure on the values of the cap on the + side of the doa.
Missing c25 pata's mentioning

API_536AE_rev3.jpg
 
Boji: C25 is right there, look for R35 ,near the 2520.
Jeff : I have 2 modules 528, 1 is a vintage ,circa 1972 , and the other is the datatronix era that you've saw in the pictures . The datatronix one has a different 2622 footprint, the room is for a jensen JE 6110K-A PC . And that footprint is the same as the ED's xfmr . Following the tracks it's seems that there's a little mod on them. the way that the pad switch is connected , and there's an R 5 that it isn't on the schematics that us have.( try to find R5 on yours).i will post you a pict tomorrow, now is too late.
regards.
pedro.
 
your phantom cap is in the wrong place. It should be between the 10k and 6.8k's
It most certainly is!

Thank you guys for taking the time to look and offer your suggestions!  ;D
 
If you take a closer look at the backdrop on Jeffs  website, I think you will find what you are missing.  ;D

 
Joechris said:
If you take a closer look at the backdrop on Jeffs  website, I think you will find what you are missing.  ;D
:D :D :D :D  Sort of, yeah. The level pot feeding the pan pot needs some value tweaking.  :eek:  It was kinda just a pretty picture on paper.
 

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