CLX-VU Build Thread (DBX 160VU ) UPDATE: REV 3

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Hi all,

I will be stocking meters for this project. The meters will be 1mA FSD with the scale pictured. The pointer will be white and the LEDs will also be white.

Please see attached meter scale. The meter will fit the DIY racked and Collective Cases case.

The meter will cost $33.00AUD each plus postage to your destination.

If you order more than 2 meters the price is $30.00AUD each.

I will be ordering the meters next month. I will post back when they are in stock. PM me if you are interested.

Kind Regards,
Ladislav
 

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When using dbx 200 cans. It need R27 (distrortion trim) but what R25,R64,R66,R102 and C16 do?

Do i need use matched cans for stereo operation?
 
late said:
When using dbx 200 cans. It need R27 (distrortion trim) but what R25,R64,R66,R102 and C16 do?

Do i need use matched cans for stereo operation?

As mentioned before, any part that says "TRIM" is exactly that, faithful to the original schematic, used to trim the other parts. Its up to the user themselves if they feel the need to trim any part. Nowadays with more precision parts I haven't ever found the need to "trim" any part, but better to have a space if you need it than not.

Matching cans? Wouldn't hurt. Sometimes the cans have a number on them, and they are the same number in stereo equipment (the old noise reduction units) I haven't personally run any tests.
 
abechap024 said:
late said:
When using dbx 200 cans. It need R27 (distrortion trim) but what R25,R64,R66,R102 and C16 do?

Do i need use matched cans for stereo operation?

As mentioned before, any part that says "TRIM" is exactly that, faithful to the original schematic, used to trim the other parts. Its up to the user themselves if they feel the need to trim any part. Nowadays with more precision parts I haven't ever found the need to "trim" any part, but better to have a space if you need it than not.

Matching cans? Wouldn't hurt. Sometimes the cans have a number on them, and they are the same number in stereo equipment (the old noise reduction units) I haven't personally run any tests.

Ok. One seller have matching option. So i think that it is for stereo. Anyone have samples with dbx 200 and that 2180? I am not sure what to use.
 
Hi!

I got my board today and I'm starting to gather BOM to order from Farnell and some local shops.
I already have few 500 uA VU meters here so I would like to use one. Those are cheap chinese from dealextreme - CHECK THE LINK

I'm wondering what resistor should I use for this type of meter?
Since 1mA meter uses 3K3 and 100uA uses 10K, is my assumption correct I should use 6K8 resistor?
Or it is impossible to use 500uA and I should get 1uA or 0.1uA VU meter?

thanks!

Luka
 
Guys..

I am building a 160VU rev 2 with the original VCAs... I wired up one PCB. What I'm getting at the output is a mild triangle wave (with no input) and nothing happens if I apply any input. More over, if I wiggle the ratio knob between 1.5 and 2 it makes (physically, not on the output) a sizzling sound from the knob as if it were in short circuit or something. And there's a bit of resistor cooking stink from it as well.

I got the 200 VCA which the seller says is for the 160VU. The footprint obviously matched, except for one pin which wasn't present on my VCA modules, so there was nothing to solder into the hole on the PCB. I don't have the PCB here, but it should be either the GND, 112 or COMPH, but probably GND.

Any ideas? Should I abandon all hope and build the THAT version?
 
baadc0de said:
usekgb said:
Have you checked for DC on your ratio pot?

Heh, there is indeed +15VDC on the ccw and -15VDC on the cw ... but why?

Thats what you want for the ratio. Double check your wiring, thats were my builds usually get fouled up. (Make sure your using the rev 3 build manual)

Also don't worry about extra holes on the PCB that is fine. enless its something simple like ground then just solder a wire to the mu-metal cover and ground it, but they usually had ground on them.

Did you take note of all the different components you have to install for the 200 series vca?

try bypassing the control voltage, and see if signal is even getting through the vca.

 
abechap024 said:
baadc0de said:
usekgb said:
Have you checked for DC on your ratio pot?

Heh, there is indeed +15VDC on the ccw and -15VDC on the cw ... but why?

Thats what you want for the ratio. Double check your wiring, thats were my builds usually get fouled up. (Make sure your using the rev 3 build manual)

Also don't worry about extra holes on the PCB that is fine. enless its something simple like ground then just solder a wire to the mu-metal cover and ground it, but they usually had ground on them.

Did you take note of all the different components you have to install for the 200 series vca?

try bypassing the control voltage, and see if signal is even getting through the vca.

Yup, using rev 3 manual (but Rev 2 PCB!).. going to check the wiring again, and see if there's anything funny happening there..  my case has IN / OUT / GR instead of IN / GR / OUT that the manual has so maybe I did something there, I know I was aware of it, but it might have slipped..

I have grounded the 200 can to no effect. Yes, I did use the silkscreen values of resistors that didn't have (T) in parenthesis, and installed the R27 trimmer, Q7 transistor, R28 resistors etc..

I'm not sure how to bypass the CV..

btw, I just saw this: http://www.acsoundstudio.com/DIY/160vu/BOM/2ndREV/Information/PCB_Board.jpg is this also a problem on the REV2 board? If so, I have it rotated the wrong way (same as on silkscreen) so maybe that's why I'm getting triangle wave output?

Thanks for the help guys!

EDIT: having changed the transistor orientation, the output pot now works and the unit passess a weak sine signal. So far so good, off to see if I can up the signal to normal level or if something else is amiss :) but my scope died, so I can't test everything else, I'll just have to improvise or wait for a new one..
 
I finished one side of my dual unit today. It's working perfectly on the first power up but I haven't calibrated it precisely yet.
Very nice compresson on kick and snare drums !

23hw2vc.jpg


9020jb.jpg
 
Hi!

I've started shopping parts for my V3 board.
I noticed that BOM file for THAT build on the first page is not the same as BOM included in V3 pdf!
When I bought resistors from the CLX_VU bom THAT CHIP.pdf and stuffed most of them, I noticed that some are missing. Then compared it to clx_manual_rev3.pdf and saw there's a difference. So advice for everyone - make sure you use latest BOM!! And that would be the one included in manual_rev3 document!

Now I have few questions.
1) Some resistor values are unobtainable in my local shops. If I for instance need 23K2 value, is it ok to use two resistors in series (22K1+1K1) or in parallel (2x47K)? I have this issue with values 23K2, 6K04, 5K49, 133K, 22Meg.
Whould there be issues if I do paralleling and serial connecting to achieve required value?

2) What if I use closest obtainable value? For instance if I use 6K19 instead of 6K04, since this 6K19 actually measures 6K13 would that be okay?

3) Also I have weird situation with 4M7 resistor (R52). When reading color code on it, it says it is that value. But when I measure it with my multimeter I get 5M6 value. That is too much off! Should I trust its actually 4M7 and assume my multimeter is acting weird on such high values (it is set to max 20Meg range... can't use lower setting since lower is 2Meg)?

:)
 
Shot, whats the tolerance of that resistor?  Best to stick with 1% (or better in certain circumstances) when you can, less issues with variation, but when you get up there into the Mohms, the swing can get pretty hairy.
 
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