PASSIVE RELAY-BASED CONTROLL ROOM KITS BUILD/SUPPORT TREAD

[crisotop]

Chekc the relays, seems like one is sticky

cheers
christoph

 

[kibadachi]

Hi Cristoph,

Thanks for the reply. that would mean this sticky relay is used every thirth and fourth time.
I tried to find some info on how the resistors and relays are combined, with no luck. It seems one component is used with every thirth and fourth step. By the schematics here i just see the parts but not the real math to combine the resistors to the right value. If you know a topic where this is handled feel free to chime in.


Grtx,

Jeffrey

 

[crisotop]

Haven't thought that through either, but maybe you are able to feel/hear the relay clack and find the dodgy one?

good luck,
christoph

 

[Igor]

Check the voltages across relay's coils, on relays marked 2R and 4R on PCB. Check resistor's values at steps 2 and 4 as well.

 

[DAN_000]

Hi Igor,    shem_audio.gif  link seems to be broken,  can you repost it ?
Thanks!

 

[Igor]

Right-click, save as....

 

[DAN_000]

Thanks, link is up again.

 

[Rafita]

Hi Igor if we want to add a plasma display to the CRM we need to add another transformer , rigth for the +/- 15v rigth ?

if Each display runs on approx. 20 mA 245V, 30 mA +/-15V.


can use this ?
http://mx.mouser.com/ProductDetail/Pulse/BV020-54220/?qs=90dkOR22QT7qW4znkoNrsw%3d%3d

Thank's for all your help.

my sontec 8 was done last month , i'll post some pictures later , and sound examples , rigth now it's been used on a mixing session , my friend is raving about it .

 

[Moby]

can use this ?
http://mx.mouser.com/ProductDetail/Pulse/BV020-54220/?qs=90dkOR22QT7qW4znkoNrsw%3d%3d

If you need 30ma than you can't use 0.35VA (7ma) transformer

 

[plumsolly]

hi are any of these power supplies better than the others (or are any not appropriate at all)
http://mouser.com/Power/Linear-Switching-Power-Supplies/_/N-wp5hZscv7?P=1z0wdj3Z1z0y706Z1z0z54rZ1z0z5fmZ1z0wdd4Z1z0wdceZ1z0wcriZ1z0waurZ1z0wcr6Z1z0wbmwZ1z0wdc0Z1yzxqxtZ1z0wdbrZ1yzxskcZ1z0wcqiZ1z0wcflZ1z0wbdhZ1z0wd8cZ1z0iwjhZ1z0wcquZ1z0wcqsZ1z0wbn5Z1z0wdcwZ1z0wda1
thanks for your help, Ben

 

[rob_gould]

Hey Ben,

Any 30W 12V 2.5A will be OK. 

This

http://gb.mouser.com/ProductDetail/Mean-Well/PLP-30-12/?qs=sGAEpiMZZMu0oxGuRuNKH2AbvLnMOowNFp3ta1JkQBI%3d

will work.  I can't see the prices of all the options because Mouser won't ship some of the stuff on that page to the UK, but I don't thinnk there's any need to spend more that the $ equivalent of £20 - £25

 

[plumsolly]

Thanks Rob! - Best, Ben

 

[misioka]

Hi

What alps encoder J must use (resolution, impulses)

on controler pcb condensers are in pf or other value.

Thanx

 

[plumsolly]

Hey Igor, where did you get your knob - I've had a hard time finding ones without markings that I like the look of.  Thanks, Ben

 

[TheGuitarist]

Hey,

Just wondering if its possible to turn one of the inputs into a mono output for a single speaker, or would this require heaps of pcb modification.

 

[Igor]

Not much...just cut some traces, add some wires
Knobs are available from Farnell, Mouser, etc...many types.
I found mine in local electronics store

 

[crisotop]

I just built a t-pad to attenuate my active monitors, but I feel like the impedance doesn't really match, since I have sudden volume jumps at certain steps of my crm. What's the typical output impedance of the crm? My speakers have an input impedance of 10k.

Thanks!
Christoph

 

[Igor]

In general: attenuator's load for precision steps should be 3k each side, plus or minus, to ground.
It already terminated with RL1, LL2, 3, 4. For 10k amp(active speaker) input impedance, Rl should be 4k3.

 

[crisotop]

thanks Igor - so to get this straight: MY H-Pad in between the crm output and my active speaker input should have a ~5k input impedance (this is the load for the crm, roughly 2k on each +/- leg and a 1k shunt) and a 4k3 output impedance (this is what the active amp 'sees').

Many thanks!
christoph

 

[Igor]

I quite can't understand why do you need a pad at the output....anyway.
Try to do it as two L-pads, if Rl=4k3, each pad is 10k input resistance, both are grounded.