MUFF WIGGLER Forum Index
 FAQ & Terms of UseFAQ & Terms Of Use   Wiggler RadioMW Radio   Muff Wiggler TwitterTwitter   Support the site @ PatreonPatreon 
 SearchSearch   RegisterSign up   Log inLog in 
WIGGLING 'LITE' IN GUEST MODE

Dotcom modules in new cab not powering up
MUFF WIGGLER Forum Index -> 5U Format Modules  
Author Dotcom modules in new cab not powering up
Suburban Bather
I'm following this diagram http://synthesizers.com/power.html#power3

I have an entry system and I just built my own addtional 22-space cab which has- QDH20 DC Power Cable Harness for 20 Modules
Q103 DC Interface Module
QIC-12 QIC Inter-Cabinet DC Power Cable - 12"

The two actual modules I have installed in the new cab- Q-115(reverb) and Q-109(EG) are not working. The Q109's led does not light up when I press the gate button, and I tried running audio through the reverb and got nothing at the output.

Any ideas what the problem may be? I just sent an email to Dotcom, but I was wondering if anyone here has experienced the same problem before. This is a real bummer, I put hours of work into building a cab and when I'm ready to fire it up and try out the reverb, I get nothing very frustrating this is not cool at all Rage!
Luka
do you have a DMM or anything to probe the rails with?
Suburban Bather
No multi meter here. I've been meaning to buy one for quite some time, but I only make cables. So, I never bothered buying one.

Also, I forgot to mention that on my Q-137, none of the power leds light up. It works fine though, no problems with the entry system cab. I'm just not getting any power to the new cab, or at least I think thats what's happening.
Luka
kinda hard to tell whats going on without any diagnostic tools
needle in a haystack

prob best to take them to someone who has some tools and report back or send em somewhere to get looked at

sorry cant be much more help confused
Suburban Bather
Thanks anyways Luka, I'm assuming Roger will porbably just have me ship the Q-103 back, but we'll see.

I guess I should just go ahead and get a multi meter incase anything like this ever happens again.
Luka
it is pretty useful thing to have, even if you are just checking the continuity of your cables
JohnLRice
You got a lot there that you can narrow things down with, even without a meter. But . . you should get a meter and they are dirt cheap for a usable one. Look for a used FLUKE on Ebay, like the model 8026B, I've seen them go for $10 to $20. Or Radio Shack and most big hardware stores have something for around $20

First off . . I don't have a Q-137 but looking at the picture the output DIN jack and LEDs are right next to each other. I'd pull that module out and see if the cable jumper(s)/header(s) are plugged into the circuit board correctly.

best of luck!
suitandtieguy
is the LED board on the power entry module plugged into power at all?
Suburban Bather
Thanks fellas,

As soon as I get off from work, I'll pick up a digital multi meter from Rat Shack. I'll pull the Q-137 out and take a look at it LED board.

I don't know what exactly I'm doing, but I'm sure this will be sorted out soon.
Suburban Bather
Ok, I got a DMM. Pulled the Q-137 out and it looks like the leds are soldered to the pcb board. I don't why I never see any of them light up, but everything seems to work for my entry level cab. I checked the DC output jack for continuity and its fine.

I check for continuity on the cable harness in my new cab and its fine. What else do I check? I'm totally new to trouble shooting electronics.
Luka
sometimes when you plug in a bad module you will notice the LEDs in your powersupply dont come on. this is a tell tale sign that there is something screwy going on in your module

does you psu or distro board have on board LEDs and if so do they light up when the case is powered up without the modules? and .. when you plug the modules in do they go out?
Luka
is there any other modules in this case?
Suburban Bather
Just to make sure, I'm referring to the voltage indicator leds on the power interface. There are no leds on the actual power supply.

Ok, this is going to take a moment then. My entry system is completely filled with modules. So what you're saying is to disconnect the power on all of my modules in my entry system cab and then turn the power on to see if the voltage indicator leds light up?
Luka
ok well before you dismantle the whole thing
lets try eliminate simple problems
pull out the cable harnesses for you modules and test the signal on each wire

i know that my power cables connecotrs are really easy to dislodge when you pull on the cable the wrong way

next step would be to check the power cables are going into them modules in the correct way
Suburban Bather
It appears that the cable harness is attached directly to the power supply, I'm not sure if its going to be possible to check those wires. The modules in my entry system work fine and its impossible to connect the power harness cables to modules the wrong way since the connectors are keyed.

I think all I can do for now is see if disconnecting all modules will change anything on that led voltage indicator problem.
Suburban Bather
Roger just emailed me back. It was a stupid error on my part. I'm totally relieved and embarrassed at the same time.

There are two cables that need to be plugged into the Q-137. One from the psu and the other is one of the cables off of the power cable harness. d'oh!

Thank you everyone for your help!
Luka
so the other modules were working?
Suburban Bather
Yes, they just weren't getting any power, because the Q-137 was missing the connection that feeds power to its voltage indicator leds and the DC out jack.
Luka
im glad it worked out!

lucky we didnt get bogged down in anything too deep
Suburban Bather
Aye!
Guinness ftw!

As soon as I finish getting my modules plugged back in, I can finally try out my new spring reverb. However, I don't think I'm going to be able to resurrect a patch I've been waiting to record with very frustrating Oh well, maybe it will bring something even better on.

Thanks again for trying to help me figure this idiotic mistake out.
suitandtieguy
it's not idiotic. it's a simple mistake, which is why i asked about it.

in fact, the Q137 that i have came to me with that board unplugged.

i'm not using it, though. i have my PSU wired right into a power strip. i'm so ghetto.
JohnLRice
I'm glad you got it figured out, SB! w00t

I'll bet most of us have gotten stumped over something that, once figured out, seems really simple.
Luka
so many times!
so many times...
smile

these sorts of things give you some strategy when you encounter future problems so it isn't necessarily a bad thing to stumble over a few problems
MUFF WIGGLER Forum Index -> 5U Format Modules  
Page 1 of 1
Powered by phpBB © phpBB Group