PASSIVE RELAY-BASED CONTROLL ROOM KITS BUILD/SUPPORT TREAD

[Siegfried Meier]

Success!!!

I had changed R12 and R14 before as per the top post, but Igor's original thread note said to:

"Try to change R13, R14 to 1k, and see what happens."

So, I did and now it seems to work!!  But, I'm curious as to why it's working in SO many other CRM's, and not here?

Haven't got time today to plug it in and listen, but it appears to function as normal!

 

[zenmastering]

Welcome to my dyslexia...although if you look at the schematic it's pretty straightforward.

You were looking for a control-knob?

http://il.farnell.com/jsp/search/altsSubs.jsp?type=acc&sku=1520809

Some don't like this one, however. Poking around a surplus store might be an idea (and fun!)

Cheers,

Graemme

 

[gec]

Hi, I finished my unit but I have a problem only on the right channel: every two steps of the encoder the output is muted...
0,-1k  -2,-3:no output  -4,-5k  -6,-7:no output...and so on...I already resetted the unit.
I think the problem should be in a relay (I already checked for bad solders on every joint), can you point me to wich relay? Or how can I check it?

thanks, Daniele

 

[gec]

Solved!!!
RA44 was the problem, wrong value (61K9 instead 619).
Daniele

 

[Igor]

Dat's common thing. We have a huge stock of resistors, it takes about a cube meter space.
Every time we buy resistors, we check them before placing in stock.
Guess what.
About every 200'th package of resistors we receive has K instead of ohms or something like this.

Strongly recommended: even if you ordering the parts from good, proven suppliers like Farnell/Mouser/Digikey,

CHECK EVERY COMPONENT BEFORE INSTALLING TO PCB.

De-soldering resistor from 2-layer, 2Oz PCB isn't a prob, the traces arent't comes off, like in case of China pcb's,
but in case of wrongly placed chip etc, it can be headache unless you have a desoldering station, blower, etc.
I use Hakko808 in this case and highly recommend this toy.

 

[bobine]

A6833 obsolete??

Hi... I got my "Christmass Edition" boards last summer. The relays have been out of stock at Mouser for the past five months but are due in April so I began to order my parts today...

Apparently the Allegro A6833SEP-T driver chip is out of stock everywhere and won't be reordered since it is obsolete.

I don't want to order $200 worth of parts if I can't get this key component.

Is there a substitute or replacement?  Or has the passive CRM passed me by?  :-[

b

 

[tomcat]

Farnell Germany does have some stock.

 

[zyzlik]

Hi! Is it possible to replace MM5540, A6833 by any other? I can't find it in Farnell. Please, help.  :'(

 

[choko]

Hi,

It's choko the newbee.
I wake up early this morning to finally finish my crm. I was so excited !! The last problem that i meet was the vga cable... evry vga cables that i found had the 4th pin  gnd... so i bought to connectors and 8 wires cable...i make my own vga cable with pin 5,6,7,8,10 straped and nothing to the 11,12,13th pin.
Then i finally powered up my crm, the controler show me V20 and -40, but the in4, out1 and sub led are blocked....I can modifie the level of the trim, save a new trim, but nothing else....
The A6833 and the 7805 are very hot....
Please help me... do you have any suggestions????
I'm very new in this sport... the only thing that i build before is a SSL4000 compressor, it was so easy!!
Sorry for the inconvenience, but i realy need your crm.
Thank you for your answer
regards

 

[tomcat]

A6833 orientation is correct? Somebody did the same mistake before a few pages back

 

[choko]

Hi,

Thank you tomcat, the A6833 orientation was wrong... what a pity!!
Now it work but :

-no led lighted for : in1, IN3, SPK2, Mono, Trim, Dim & TB !!! but the relays click when i switch it on
- SPK the relays click from 0 to -42, then nothing from -43 to -62, then click when cut
-Trim + spk (or in) the relays clicks from -2 to 20, but no click from -3 to -20
-Trim + dim : click to -23, then nothing from -24 to -50

Any ideas??
Perhaps the passive crm was a bit too difficult for me...

thank you for your patience;-)

 

[funball2]

hi choko,



-no led lighted for : in1, IN3, SPK2, Mono, Trim, Dim & TB !!! but the relays click when i switch it on

check the leds are right position

- SPK the relays click from 0 to -42, then nothing from -43 to -62, then click when cut

your input trim is not on zero

-Trim + spk (or in) the relays clicks from -2 to 20, but no click from -3 to -20
-Trim + dim : click to -23, then nothing from -24 to -50

let me see if i find it on my crm ....

Any ideas??
Perhaps the passive crm was a bit too difficult for me...

not

thank you for your patience;-)

your welcome

funball

[/quote]

 

[funball2]

hi choko,

Any ideas??
Perhaps the passive crm was a bit too difficult for me...

i think beside the leds  your crm is working

cheers

funball

 

[choko]

Hi funball,

I think i'm about 12 hours to be the hapiest man in my town!!!...
It was the leds!!!... I'd have to be ashamed, but ...
The last challenge is to hear the silence in my studio tomorow... and to plug my Dsub25. I have rme dsub (male & female normaly used for a neve somator), i'm not sure with the way to wired it, but i passed the first step, then i follow the newbie chance...

Thank you funball thank you igor !

 

[choko]

success !!
first master with my own crm ;-)))

It sounds like hapiness!...

 

[bluesbaz]

've had to put this thing down for a while because I got frustrated. Im back and hoping someone might have time.
I was testing today and this is what I get on startup. None of the relays click.

http://youtu.be/pSFOlQvABhw

 

[bluesbaz]

Wow, Im really starting to sour on Igor and this whole project.
Can I not get some love here? :'(

 

[bluesbaz]

Lame, just lame!
-s

 

[Igor]

@bluesbaz: sorry, I had really busy time. Now, let's fix it.
Please explain what are the problems with your build. I will try to figure out and write down here.
The CRM is not an easy project, for the very worst case, we'll do same as did with MixBuzz1 troubleshooting with some guys from here:
I need you on skype, with scope, DMM, soldering iron and the patient (CRM),
4 of MixBuzz1's were solved for approx. 1.5 hour each, the CRM is less complicated.

 

[Igor]

First, BUMP to all people who had a questions, let's fix your CRM's.

Many people asked about hooking a SUB.

With balanced SUB, with XLR L and R inputs, should be no problem,
just add 1-2 db to compensate level.
Remember, aye, this CRM thing is absolutely passive!!! I don't know how to make it cleaner, but there can be a level drop issue.
This way, press and hold trim than SUB, see 0 at level display, adjust for +2, press TRIM again to exit.
Set initial setup like IN1, SPK1, -50,  no other buttons lit up; save it by pressing TRIM for 10 sec, and the trim value will be stored as well.

If you have an unbalanced SUB with MONO input:

2x (INA137 or INA134 or THAT1246 etc) bal. line receivers; 1xNE5534, some resistors, stuff, and, of course, +/-15V 0.1 A power supply.

See picture attached.