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General Discussions => The Lab => Topic started by: pucho812 on January 19, 2021, 11:02:05 PM

Title: AMS service manuals RMX16 & DMX15
Post by: pucho812 on January 19, 2021, 11:02:05 PM
does anyone have a copy of either or unit's service manual?
Title: Re: AMS service manuals RMX16 & DMX15
Post by: gyraf on January 20, 2021, 04:05:22 AM
..I've never, ever, seen any "in the wild", there's an empty spot there in my library..

/Jakob E.
Title: Re: AMS service manuals RMX16 & DMX15
Post by: David Kulka on January 20, 2021, 01:39:40 PM
No true service manual was ever published or distributed to dealers. AMS dealers got service bulletins and sets of original schematics but they were never available to the public. I've seen copies of a so-called RMX16 service manual that was published by AMS, but it only has limited calibration info and a few service hints, some of which are in the easier to find owners manual.
Title: Re: AMS service manuals RMX16 & DMX15
Post by: pucho812 on January 20, 2021, 03:37:33 PM
..I've never, ever, seen any "in the wild", there's an empty spot there in my library..

/Jakob E.

Mine too. I love to have service manuals of all the studio gear we run.
Title: Re: AMS service manuals RMX16 & DMX15
Post by: living sounds on January 20, 2021, 06:19:51 PM
Sent you a PM.
Title: Re: AMS service manuals RMX16 & DMX15
Post by: Whoops on January 20, 2021, 10:14:27 PM
AMS dealers got service bulletins and sets of original schematics but they were never available to the public.

It would be great if any of those copies would be made available publicly now
Title: Re: AMS service manuals RMX16 & DMX15
Post by: Walrus on January 21, 2021, 05:27:58 AM
There is these......
https://drive.google.com/file/d/1-DvtSJlsgY_H1c6l0Sp2_T9rF6t4Fpv9/view?usp=sharing, https://drive.google.com/file/d/18amA23EZd6_qDq2uhvoqbxgc3SfNmEye/view?usp=sharing, https://drive.google.com/file/d/1nnvhk8UtUP05W6YTcL3PwMv5qjAdL2ay/view?usp=sharing, https://drive.google.com/file/d/1z2wB2lrFyOM5TEnnQiP3ZiH3z3JLn9Ip/view?usp=sharing
Title: Re: AMS service manuals RMX16 & DMX15
Post by: gyraf on January 21, 2021, 06:02:17 AM
!! Thanks!
Title: Re: AMS service manuals RMX16 & DMX15
Post by: bpucekov on January 21, 2021, 12:23:07 PM
There is these......
https://drive.google.com/file/d/1-DvtSJlsgY_H1c6l0Sp2_T9rF6t4Fpv9/view?usp=sharing, https://drive.google.com/file/d/18amA23EZd6_qDq2uhvoqbxgc3SfNmEye/view?usp=sharing, https://drive.google.com/file/d/1nnvhk8UtUP05W6YTcL3PwMv5qjAdL2ay/view?usp=sharing, https://drive.google.com/file/d/1z2wB2lrFyOM5TEnnQiP3ZiH3z3JLn9Ip/view?usp=sharing

Than you
Puc
Title: Re: AMS service manuals RMX16 & DMX15
Post by: mjrippe on January 21, 2021, 02:29:49 PM
Amazing.
Title: Re: AMS service manuals RMX16 & DMX15
Post by: Whoops on January 21, 2021, 02:38:52 PM
Thank you so much
Title: Re: AMS service manuals RMX16 & DMX15
Post by: abbey road d enfer on January 21, 2021, 04:56:45 PM
There is these......
https://drive.google.com/file/d/1-DvtSJlsgY_H1c6l0Sp2_T9rF6t4Fpv9/view?usp=sharing, https://drive.google.com/file/d/18amA23EZd6_qDq2uhvoqbxgc3SfNmEye/view?usp=sharing, https://drive.google.com/file/d/1nnvhk8UtUP05W6YTcL3PwMv5qjAdL2ay/view?usp=sharing, https://drive.google.com/file/d/1z2wB2lrFyOM5TEnnQiP3ZiH3z3JLn9Ip/view?usp=sharing
Thank you for making these available.
Now, who wants to clone one?  ;D
Title: Re: AMS service manuals RMX16 & DMX15
Post by: living sounds on January 21, 2021, 06:57:22 PM
Now, who wants to clone one?  ;D

Redesign, the original is a nightmare. And there are endless revisions and combinations of subboards. Sounds great though, if it works. Mine has been in the shop since early December now. Hope they can fix it. I know I can't this time (at least not in a reasonable amount of time).
Title: Re: AMS service manuals RMX16 & DMX15
Post by: pucho812 on January 21, 2021, 11:11:54 PM
There is these......
https://drive.google.com/file/d/1-DvtSJlsgY_H1c6l0Sp2_T9rF6t4Fpv9/view?usp=sharing, https://drive.google.com/file/d/18amA23EZd6_qDq2uhvoqbxgc3SfNmEye/view?usp=sharing, https://drive.google.com/file/d/1nnvhk8UtUP05W6YTcL3PwMv5qjAdL2ay/view?usp=sharing, https://drive.google.com/file/d/1z2wB2lrFyOM5TEnnQiP3ZiH3z3JLn9Ip/view?usp=sharing

Mother of god, that is awesome. Many thanks. You Sir, are a delight.
Title: Re: AMS service manuals RMX16 & DMX15
Post by: David Kulka on January 22, 2021, 11:54:51 AM
There is these......
https://drive.google.com/file/d/1-DvtSJlsgY_H1c6l0Sp2_T9rF6t4Fpv9/view?usp=sharing, https://drive.google.com/file/d/18amA23EZd6_qDq2uhvoqbxgc3SfNmEye/view?usp=sharing, https://drive.google.com/file/d/1nnvhk8UtUP05W6YTcL3PwMv5qjAdL2ay/view?usp=sharing, https://drive.google.com/file/d/1z2wB2lrFyOM5TEnnQiP3ZiH3z3JLn9Ip/view?usp=sharing

Wow, I stand corrected and am amazed. I've been steadily working on AMS gear for almost 15 years and thought I'd seen it all. But I never saw that service packet before, or any schematics that were visible to the public.

Anyone who takes the cover off of an AMS delay or reverb will soon realize that even with schematics, they're still incredibly difficult to service, with all sorts of production variations and pitfalls. But if you're a good tech and you make notes and take photos as you go along, you'll have a decent shot at fixing the not-too-difficult problems.
Title: Re: AMS service manuals RMX16 & DMX15
Post by: pucho812 on January 22, 2021, 01:02:40 PM
Indeed. Usually start with a vacuum as the foam on the bottom plate is surely rotted away after decades in use
Title: Re: AMS service manuals RMX16 & DMX15
Post by: pucho812 on January 23, 2021, 09:55:08 PM
RMX is back in service with a battery change :)

However our 15-80 is most perplexing.  PSU is fine and the unit functions but  I am trying to isolate why my channel B output is acting funny.

(with output switch set to mixed)
1.Channel A input pot raised, I get audio on both outputs. The audio has random spurts of digital nose.
2.Channel B input pot raised  with Channel A input raised does not effect anything on the outputs. They stay as in #1
3.Channel A pot lowered to infinity and I have no audio at the output
4.Channel B pot is raised with channel pot lowered to infinity and I have no audio at the output as in step 3
I can repeat  and get the same results regardless of input switch set to mixed or individual

(With output switch set to individual)

A. Channel A and B input pots both raised, I do not get audio on the channel B output, just random bursts of audio +noise
B.with input switch mixed I get the same results as in step A.

I have swapped the input cards and the DAC cards around, there was no change.

I am leaning towards a problem on the ADC card.  But still doing further testing.
Title: Re: AMS service manuals RMX16 & DMX15
Post by: radardoug on January 24, 2021, 12:15:54 AM
More likely to be the MCB. But first, have you changed the ribbon cables?
Title: Re: AMS service manuals RMX16 & DMX15
Post by: pucho812 on January 24, 2021, 12:31:32 AM
More likely to be the MCB. But first, have you changed the ribbon cables?
I did not change ribbon cables.

However now I started the following combined with the previous mentioned issue. With no audio it has a timed tick. Meaning it will produce a tick sound at both outputs and is consistent every second toto seconds.  If I run audio, I get the amor mentioned problem but now it sounds like there is a gat opening and closing on it.  so  for example if I have an audio loop going into it and I am listening to the  dry signal + delayed signal, I'll hear the delay signal but it will be signal there no signal and then come back again.  very weird.

 
Title: Re: AMS service manuals RMX16 & DMX15
Post by: radardoug on January 24, 2021, 01:30:30 AM
Make sure the switches on the MCB card are set up correctly. What you are describing is the unit not switching in the memory cards correctly
Title: Re: AMS service manuals RMX16 & DMX15
Post by: pucho812 on January 24, 2021, 01:51:25 AM
Make sure the switches on the MCB card are set up correctly. What you are describing is the unit not switching in the memory cards correctly

will take a look at that... although I didn't flip any of the dip switches.  thanks :)

So far I have a ram3 in slot 12 and a ram4  in slot 16 PCB installed.
 the rest of he cards seem to match but will go over it all again. 
Title: Re: AMS service manuals RMX16 & DMX15
Post by: radardoug on January 24, 2021, 03:57:48 PM
Memory cards should be in adjacent slots starting from 16. Theres your problem. And so it should be set up for 1 card for each channel, and the size switch set correctly
Title: Re: AMS service manuals RMX16 & DMX15
Post by: pucho812 on January 24, 2021, 05:09:01 PM
Memory cards should be in adjacent slots starting from 16. Theres your problem. And so it should be set up for 1 card for each channel, and the size switch set correctly

o.k.  that is good to know. Now I need to sift through documents to find dip switch settings
Title: Re: AMS service manuals RMX16 & DMX15
Post by: pucho812 on January 24, 2021, 07:00:10 PM
rather then go back and forth,

Here is the current layout inside the unit and dip switch settings.
Title: Re: AMS service manuals RMX16 & DMX15
Post by: living sounds on March 12, 2021, 09:51:04 AM
Talked with the repair shop today that had my 15-80s since early December. They rebuild the CPU board (battery damage) and replaced some questionable logic ICs. They had been stalling (I called every few weeks) and now they told me that they cannot get it to run reliably and won't attempt to repair it any more...

I had replaced all the ribbon cables, pots and all electrolytic tantalum caps 3 years ago, and it was running fine for ca. 2 years afterwards...

Since I will retrieve it and have to look at it myself again, any suggestions what to try would be greatly appreciated.
Title: Re: AMS service manuals RMX16 & DMX15
Post by: radardoug on March 12, 2021, 03:14:27 PM
Often once the micro has had the battery problem, the board gets very flaky. And some early AMS boards with black solder mask are very dodgy. When the battery cleanup is done it is mandatory to change all the transistors in the battery circuit. This affects reset operation.
You can buy new micro boards from David Kulka which are all cmos and better built! (I designed them).
Title: Re: AMS service manuals RMX16 & DMX15
Post by: living sounds on March 12, 2021, 07:23:54 PM
Thanks! I will have a look at the transistors on the card. I had replaced a couple (in the battery loading circuit) and I think they replaced more. If all of it doesn't help I will order that board from Studio Electronics. Not cheap (especially with the current shipping insanity, + taxes etc.), but I'm glad there are people making these availible.  :)

Might still be a problem on the mainboard...   ::)
Title: Re: AMS service manuals RMX16 & DMX15
Post by: radardoug on March 12, 2021, 09:53:34 PM
The other things that cause problems are the ribbons, but you have changed them I think? And also the motherboard sockets. If changing the transistors does nothing, try changing the motherboard socket.
The software that drives that board is partly on the micro, and partly on the effects extender card. So those ribbons are critical to keeping the micro happy.
Title: Re: AMS service manuals RMX16 & DMX15
Post by: living sounds on March 13, 2021, 07:58:04 AM
The other things that cause problems are the ribbons, but you have changed them I think? And also the motherboard sockets. If changing the transistors does nothing, try changing the motherboard socket.
The software that drives that board is partly on the micro, and partly on the effects extender card. So those ribbons are critical to keeping the micro happy.

Thanks! Yes, I remade all the ribbons. Do you happen to have a parts number / link for the motherboard sockets?

Obviously, the reason why a specialized repair shop would make sense (apart from their experience) is that they can simply exchange cards and find the error by elimination... But shipping this fragile unit around the world is also something I would like to avoid...
Title: Re: AMS service manuals RMX16 & DMX15
Post by: radardoug on March 13, 2021, 03:18:07 PM
I dont have a part number but I think David sells them. 22 pin double sided, .156 inch I think.
Yes, the best way to test AMSes is by board substitution. But its not uncommon to have multiple faults.
In your case, does the micro hang? So it boots up normally, and then the display will freeze or blank? Then it is either the micro card or the effects extender.
Title: Re: AMS service manuals RMX16 & DMX15
Post by: living sounds on March 13, 2021, 04:30:57 PM
I dont have a part number but I think David sells them. 22 pin double sided, .156 inch I think.
Yes, the best way to test AMSes is by board substitution. But its not uncommon to have multiple faults.
In your case, does the micro hang? So it boots up normally, and then the display will freeze or blank? Then it is either the micro card or the effects extender.

From what they have told me, it crashes unpredictably. Will fetch it next week and report back. Thanks!
Title: Re: AMS service manuals RMX16 & DMX15
Post by: radardoug on March 14, 2021, 05:48:39 PM
Do you have the ability to program eproms? If so, PM me.