MAC RACK KIT with Green MAC & DINGO PCBs Build Thread

Support for JLM Audio Kits

Moderator: Joe Malone

Online
User avatar
Joe Malone
Site Admin
Posts: 2069
Joined: Wed Jan 24, 2007 11:35 pm
Location: Brisbane, Australia
Contact:

MAC RACK KIT with Green MAC & DINGO PCBs Build Thread

Post by Joe Malone »

Image

MAC Schematic with build info for dingo changes and MAC alignment
http://www.jlmaudio.com/MAC/MACSCH.pdf

MAC PCB parts kit
Image

MAC PCB. PCB overlay has all values and there are no options.
so PCB can be assembled directly from overlay.
Notes and Errata (NEW RED COLOURED MAC PCB has all the below errors corrected)
JLM 34mm round VU meter needs D5 to D8 fitted.
LED D9 which is the meter led has A and K marking on MAC PCB are reversed . Rectangle Pad is A (+meter led)
R14 should be changed from 2k7 to 1k8 in all 500 series LA500 versions.
MAC kit now comes with all 1k trim pots replacing the 20k which makes setting the Meter 0VU easier

Image

Fit all 8 x BAT85 diodes with there Cathode POLARIZED black stripe matching the white stripe on the MAC PCB overlay
Image

Solder all BAT85 diodes while holding PCB firmly upside down on flat surface. Make sure none of the center close pads are NOT shorted together.
Image

Cut all diodes legs off at top of the solder joint and double check no solder joints missed soldering or are shorted together.
Image

If you are not 100% with resistor colour codes use a multimeter to check values as you place the resistors
Image

Fit all resistors at once bending the legs sightly outwards to hold them in place. This helps to make sure no resistors are put in the wrong position.
Image

Solder all resistors while holding PCB firmly upside down on flat surface.
Image

Cut all resistor legs off at top of the solder joint and double check no solder joints missed soldering.
Image

Fit and solder DIP8 socket in other opamp position. Make sure the POLARIZED socket matches the PCB overlay.
Image
Image

Fit and solder 2 x 0.1uF MONO caps in place.
Image
Image

Fit 1 x 100pF ceramic caps in place.
Image
Image

Fit and solder 2 x 5C2 optos in place.
Image
Image

Fit and solder IDC headers in the POLARITY shown. Do not reverse. Triangle on header indicates pin 1 which is the square pad on the PCB.
Image

The front opening in the IDC headers should both now be facing as shown below.
Image

Fit and solder Electro caps to PCB. The 4 x 100uF caps are POLARIZED so must have there long positive leg fitted to + marked on PCB overlay.
2 x 3.3uF acaps are NON polar types so can go in either way around on the PCB.
Image
Image

Fit and solder 3 trim pots as shown 20k = 203(replaced with 1k), 1k = 102 code. Place pot so trim screw is in corner shown below
Note MAC kit now comes with all 1k trim pots replacing the 20k which makes setting the Meter 0VU easier
Image
Image

Fit the three switches to the MAC from on top soldering only one front leg and checking they are all aligned before soldering the remaining legs.
Image

Threshold pot wiring
Fold the pot legs 90 degrees with log nose pliers and solder and link as shown below to make a 100k log pot out of the 2 x 200k log pots.
Slow attack mod wiring attached below as well. Orange wires can go on either way around as cap is non polar.
Image

Makeup pot wiring
If Single 10k rev log pot change R16 on dingo PCB to 10k. (If R16 20k already fitted add spare 20k across it under PCB)
or
If 2 x 10k rev log pot wire as 20k rev log makeup pot below
Image


Dingo Schematic
http://www.jlmaudio.com/JLMdINgO.pdf

Dingo PCB built with all changes that are listed on MACSCH.pdf
Note if MAC kit came with single 10k reverse log pot R16 on dingo is changed to 10k. (If 20k already fitted use spare 20k soldered across it under the PCB)
Image

Dingo to JLM111DC wiring
P- to -1
P+ to +1
S+ to +2
S- to -3
Link +3 to -2 on JLM111DC

Photo of MAC link PCB
Image

Image

The positive from the DC connector goes to the fuse holder either terminal
Then from the other fuse holder terminal to the +IN on the switch PCB
Then from the +SW to the +V on both Dingo PCB's

The negative from the DC connector goes to the -IN on the switch PCB
Then from the -SW to the -V on both dingo PCB's
Nothing goes to the 0v on either dingo PCB.
Image

Overview of the general MAC PCB wiring
Image

Overview of the general wiring without the case.
Shows most wiring is done by pre made ribbon cables
34mm VU Meters have there LED terminals on the outside with meter terminals on the inside. Meter positive and Anode of the LED on the side marked +
Image

Before plugging in any op amps 99v or OPA2604A on the dingo or MAC pcbs check you have +24v at +V and -24v at -V on the dingo PCB referenced to the 0v terminal.

Some internal rack case photo's to help
Image
Image
Image

Before plugging in any op amps 99v or OPA2604A on the dingo or MAC pcbs check you have +24v at +V and -24v at -V on the dingo PCB referenced to the 0v terminal.jlmaudiojlmaudio
Joe :-)
JLM Audio
Capturing Audio without Injury

khstudio
Posts: 3
Joined: Sun Dec 30, 2007 1:11 pm
Location: New Jersey, USA
Contact:

Re: MAC Build Thread

Post by khstudio »

Cannot read the PDF of the MAC schematic:
MAC Schematic with build info for dingo changes and MAC alignment
http://www.jlmaudio.com/MAC/MACSCH.pdf

Online
User avatar
Joe Malone
Site Admin
Posts: 2069
Joined: Wed Jan 24, 2007 11:35 pm
Location: Brisbane, Australia
Contact:

Re: MAC Build Thread

Post by Joe Malone »

khstudio wrote:Cannot read the PDF of the MAC schematic:
MAC Schematic with build info for dingo changes and MAC alignment
http://www.jlmaudio.com/MAC/MACSCH.pdf
You will need the latest Adobe PDF reader to open the PDF's. Some browsers will not open the PDF so best to download the PDF to your desktop and open it in Adobe Reader directly.
Joe :-)
JLM Audio
Capturing Audio without Injury

Mixmaster-Nate
Posts: 14
Joined: Fri Apr 22, 2011 12:20 pm

MAC PCB (C3/4) Cap Polarity + VU LED + Dingo Resistors + On/

Post by Mixmaster-Nate »

Hi JLM 'ers,

just happily building my MAC Kit on a rainy day here in Sydney...

Because I AM an absolute amateur who can read a schem to a degree (ok), so patience if you please & a couple of quick questions... :wink:

On the MAC PCB;

1. Capacitor C3 & C4 (3u3) - with the toggle switches to the left (as per your photos) what side of the terminal holes on the PCB is the positive, left or right.?? (Please see photo)
mac_pcb.jpg
2. The VU LED - my kit came with a loose LED and plastic surround, does this need to be used, or is the 'comp in' LED already installed in the VU's re; I just need to wire it up..??

On the DINGO - just some confusion (on my behalf) between the Dingo Schem and the photo on the forum for resistor values;

a) R4 - schem says 20k but photo shows different value...??
b) R6 - schem says 20k but photo shows different value...??
c) R25 - schem says 20k but photo shows different value...??
d) R13 - schem says 51R but photo shows different value...??

I've attached a photo of my DINGO with these resistors not installed yet just for reference.
dingo_pcb.jpg
The ON/OFF Switch - comparing my kit with the photos, I appear to be missing the component that is soldered to '4700' on the PCB board..? (Please see photo of my kit parts compared to JLM's assembled photo)

on_off_switch.JPG
Many thanks, Nathan... 8)
You do not have the required permissions to view the files attached to this post.

Mixmaster-Nate
Posts: 14
Joined: Fri Apr 22, 2011 12:20 pm

Re: MACSCH.pdf

Post by Mixmaster-Nate »

Oh - can any one on a Mac open MACSCH.pdf...?? I've tried browsers, Preview, Adobe Reader v8, Word, Photoshop with no luck...

Photoshop says; 'doc has security setting which prevent it from being opened'

(I'm OSx10.6)

Cheers, Nathan... :roll:

Online
User avatar
Joe Malone
Site Admin
Posts: 2069
Joined: Wed Jan 24, 2007 11:35 pm
Location: Brisbane, Australia
Contact:

Re: MACSCH.pdf

Post by Joe Malone »

Mixmaster-Nate wrote:Oh - can any one on a Mac open MACSCH.pdf...?? I've tried browsers, Preview, Adobe Reader v8, Word, Photoshop with no luck...

Photoshop says; 'doc has security setting which prevent it from being opened'

(I'm OSx10.6)

Cheers, Nathan... :roll:
Need free reader 9.1 or later to open PDF. Not sure what that means on a Mac terms except that mac users said they were ok once they had that info. PDF is only locked for changes. All dingo part changes are listed on the macsch. R4 & R6 change to 10k. One 51r changed to 1k. One 51R changes to 470nF cap. See macsch & photo for changes. 3u3 caps are bipolar so can go in either way around. 4007 is not used on power switch pcb. Vu led is the led in vu meter outside terminals.
Away with only iPhone so can not get to the PDFs until I get back on Monday night. Hope the above info helps in the meantime.
Joe :-)
JLM Audio
Capturing Audio without Injury

Mixmaster-Nate
Posts: 14
Joined: Fri Apr 22, 2011 12:20 pm

Re: MAC Build Thread

Post by Mixmaster-Nate »

Thanks for the prompt reply Joe. All sorted. :D

Here is the link for Adobe X if anyone on a Mac needs it for the future;

http://get.adobe.com/reader/?no_ab=1

Mixmaster-Nate
Posts: 14
Joined: Fri Apr 22, 2011 12:20 pm

Re: MAC Build Thread

Post by Mixmaster-Nate »

Hi again,

Before I hooked up the Dingo to Mac PCB with the ribbon cables, and before I plugged in the 99v's I tested the V+ & V- as per instructions on the Dingo PCBs; both read +24v and -24v respectively. The green power LED was lit solid on the front panel.

- However, after hooking up the ribbons and 99vs I'm no longer getting these readings and the green power LED on the front flashes on/off quickly every 2-3 secs.

- I've disconnected the ribbons and 99v's and the measured again, still no readings at V+/V- and the green LED continues to flash.

On the power PCB the 100k resistor tests fine (99.8k), and +IN/-IN measure 48.9v however when the switch is put in the on position +SW/-SW show no voltage. However there is continuity between +In/+SW and -IN/-SW when the switch is on.

I've triple quadruple checked all my resistor values and wirings, and my ribbon cables match the photos etc, so I think everything is good...

Is it time for the amateur (me) to send it in to the doctor at JLM ?? ..... :cry:

Online
User avatar
Joe Malone
Site Admin
Posts: 2069
Joined: Wed Jan 24, 2007 11:35 pm
Location: Brisbane, Australia
Contact:

Re: MAC Build Thread

Post by Joe Malone »

Mixmaster-Nate wrote:Hi again,

Before I hooked up the Dingo to Mac PCB with the ribbon cables, and before I plugged in the 99v's I tested the V+ & V- as per instructions on the Dingo PCBs; both read +24v and -24v respectively. The green power LED was lit solid on the front panel.
OK this proves the dingo and 24v 1w zeners and 99v's are correct and working.
- However, after hooking up the ribbons and 99vs I'm no longer getting these readings and the green power LED on the front flashes on/off quickly every 2-3 secs.
OK either IDC PCB header or cable header backwards or OPA2604AP plugged in backwards or solder short on MAC PCB. Flashing is the power supply going into protect mode due to overcurrent due to a short.
- I've disconnected the ribbons and 99v's and the measured again, still no readings at V+/V- and the green LED continues to flash
A short as discribed above will kill one or two of the 24v 1w zeners on the dingo making it go dead short so current overload will remain until short zener is replaced. Find short 24v 1watt zener on dingo (will measure close to 0ohms) and replace. May need all 4 24v 1w zeners replaced depending on problem to do with cabling or MAC pcb. Everything else will be fine usually. Let me know if you need some 24v 1watt zeners sent down to you if you cannot get any locally.
I've triple quadruple checked all my resistor values and wirings, and my ribbon cables match the photos etc, so I think everything is good...
Email me some photo's of the top and bottom of the MAC PCB and top of dingo PCB and wiring plugged in and I will check it over for you. Try to use macro on camera and bright lighting to get a good focus.
Is it time for the amateur (me) to send it in to the doctor at JLM ?? ..... :cry:
Not yet but we can certainly get it going for you if the photo's don't help us find the problem. :D

Basic test procedure
(Power off and on between any changes)
1. Change dead short zeners
2. Test dingos with no opamps fitted for +/-24v
3. Fit 99v to left dingo and test for +/-24v at +V 0v -V on dingo.
4. Fit 99v's to right dingo and test for +/-24v at +V 0v -V on dingo.
5. Plug in left ribbon cable from dingo to MAC and test for +/-24v at +V 0v -V on dingo.
6. Plug in right ribbon cable from dingo to MAC and test for +/-24v at +V 0v -V on dingo.
7. Align the beast
8. Enjoy
Joe :-)
JLM Audio
Capturing Audio without Injury

Mixmaster-Nate
Posts: 14
Joined: Fri Apr 22, 2011 12:20 pm

Re: MAC Build Thread

Post by Mixmaster-Nate »

Hi Joe,

thankyou again for your prompt reply!

I've tested the 4 x ZD 24v1w and the two on the left Dingo are measuring 0.0 ohms, and one on the right dingo measures 1.4k...(the other 9.98k - ok?)...so best to replace the first three...??

Can I get these online via your shop?? RS, Farnell and WES seem to only have 1.3 w'ers...

I've uploaded some webpage links on my site with hi-res pics, saves cluttering your forum up with arty photography. You can zoom in and out via your browser window/zoom.

http://www.mixosmosis.com/mac_pcb.html

http://www.mixosmosis.com/dingo_pcb.html

http://www.mixosmosis.com/POT_VU_wiring.html

http://www.mixosmosis.com/RIBBON_wiring.html

Best, Nathan :D

Online
User avatar
Joe Malone
Site Admin
Posts: 2069
Joined: Wed Jan 24, 2007 11:35 pm
Location: Brisbane, Australia
Contact:

Re: MAC Build Thread

Post by Joe Malone »

Mixmaster-Nate wrote:Hi Joe,

thankyou again for your prompt reply!

I've tested the 4 x ZD 24v1w and the two on the left Dingo are measuring 0.0 ohms, and one on the right dingo measures 1.4k...(the other 9.98k - ok?)...so best to replace the first three...??
Sent you 8 x 24v 1w zeners and IDC cable end overnight today.
Can I get these online via your shop?? RS, Farnell and WES seem to only have 1.3 w'ers...
1w or 1.3w will both work fine
I've uploaded some webpage links on my site with hi-res pics, saves cluttering your forum up with arty photography. You can zoom in and out via your browser window/zoom.
http://www.mixosmosis.com/dingo_pcb.html
10 pin header on the dingo in the photo is on backwards. Do not try to remove it. You can sometimes slide the black plastic piece up off the gold pins with a small flat screwdriver and turn it around. Or cut the end off the ribbon cable and put a new end on backwards. Or cut the keyway opening in the otherside of the header with sidecutters.

But in the ribbon wiring photo's the ribbon has the red pin1 on the correct side? Did you reterminate the ribbon cable header?
Joe :-)
JLM Audio
Capturing Audio without Injury

Mixmaster-Nate
Posts: 14
Joined: Fri Apr 22, 2011 12:20 pm

Re: MAC Build Thread

Post by Mixmaster-Nate »

But in the ribbon wiring photo's the ribbon has the red pin1 on the correct side? Did you reterminate the ribbon cable header?
Yes - when I realised the header on the Dingo board was on backwards and the same as for the Mac Link board (an error by me), I did re-terminate both ends with a new one on Dingo end and Mac Link end, so that pin 1 of each ribbon was on the right side...the middle cable end that plugs into the MAC PCB I did not change...

:?

Online
User avatar
Joe Malone
Site Admin
Posts: 2069
Joined: Wed Jan 24, 2007 11:35 pm
Location: Brisbane, Australia
Contact:

Re: MAC Build Thread

Post by Joe Malone »

Mixmaster-Nate wrote:
But in the ribbon wiring photo's the ribbon has the red pin1 on the correct side? Did you reterminate the ribbon cable header?
Yes - when I realised the header on the Dingo board was on backwards and the same as for the Mac Link board (an error by me), I did re-terminate both ends with a new one on Dingo end and Mac Link end, so that pin 1 of each ribbon was on the right side...the middle cable end that plugs into the MAC PCB I did not change...

:?
Cool. Parcel went today so you should have the 8 x 24v 1w zeners and 2 x spare IDC cable plugs tomorrow.
Joe :-)
JLM Audio
Capturing Audio without Injury

Mixmaster-Nate
Posts: 14
Joined: Fri Apr 22, 2011 12:20 pm

Re: MAC Build Thread

Post by Mixmaster-Nate »

Hi again Joe,

I got the new zd's and cable ends, thankyou! And thankyou for the follow up phone call, sorry I missed it.

I've installed the 4 x new zd's on the Dingos, re-tested and I'm getting +/-24v at VS+/- respectively on the Dingos. So that's all good again...!!

Before I turn on the power, I've done some continuity tests to see where pin 1 is tracing on each PCB as per my wiring with the ribbon cables plugged in to the Dingo, MAC and LINK boards...

There is a new photo for reference of point (a) & (d) below for you to see loaded up at; http://www.mixosmosis.com/IDC_Polarity.html

Looking at the back of the Dingo & Mac pcb, with both 10 pin IDC's at the top (NB* I've only tested pin 1/pink wire on each ribbon);

- For the left channel (#1);
(a) the left top (outside) pin of the Dingo has continuity with the right bottom (inside) pin of the MAC. Photo (a).
(b) the same pin on the Dingo has continuity with the same pin on the MAC LINK for this side.

- For the right channel (#2);
(c) is the same as above (a) for Dingo to MAC.
(d) For the MAC LINK it's the same as (b) - however it's the opposite end than the first side of the MAC LINK. Photo (d)

Hope this makes sense... :?

I still haven't powered up yet with the ribbons all connected. I fear I'll just burn out the zd's again.

Best, Nathan :D

Online
User avatar
Joe Malone
Site Admin
Posts: 2069
Joined: Wed Jan 24, 2007 11:35 pm
Location: Brisbane, Australia
Contact:

Re: MAC Build Thread

Post by Joe Malone »

Mixmaster-Nate wrote:Hi again Joe,

I got the new zd's and cable ends, thankyou! And thankyou for the follow up phone call, sorry I missed it.

I've installed the 4 x new zd's on the Dingos, re-tested and I'm getting +/-24v at VS+/- respectively on the Dingos. So that's all good again...!!
Ok cool
Before I turn on the power, I've done some continuity tests to see where pin 1 is tracing on each PCB as per my wiring with the ribbon cables plugged in to the Dingo, MAC and LINK boards...

There is a new photo for reference of point (a) & (d) below for you to see loaded up at; http://www.mixosmosis.com/IDC_Polarity.html

Looking at the back of the Dingo & Mac pcb, with both 10 pin IDC's at the top (NB* I've only tested pin 1/pink wire on each ribbon);

- For the left channel (#1);
(a) the left top (outside) pin of the Dingo has continuity with the right bottom (inside) pin of the MAC. Photo (a).
(b) the same pin on the Dingo has continuity with the same pin on the MAC LINK for this side.

- For the right channel (#2);
(c) is the same as above (a) for Dingo to MAC.
(d) For the MAC LINK it's the same as (b) - however it's the opposite end than the first side of the MAC LINK. Photo (d)

Hope this makes sense... :?

I still haven't powered up yet with the ribbons all connected. I fear I'll just burn out the zd's again.

Best, Nathan :D
The square pad under the PCB is always pin 1 of the IDC ribbon cable and header so it is easy to check. Follow my test list back up the page and just plug in one MAC PCB at a time and check you have the opamp on the MAC PCB in the correct way around. Again pin 1 is always the square pad under the PCB for the opamp as well.
Joe :-)
JLM Audio
Capturing Audio without Injury

Post Reply