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The Dub Master MIDIbox 64 -work in progress-


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Be confident man, I can tell that you had it figured out already :)

Don't worry, I go to the chat room to get these guys to give me a pat on the head too: "yes, stryd, it'll work, now off you go"

Hahahaha thanx man.  ;D

/titled/: man i never even thought about that, but thats a grat idea' man.

I'll look into it, right now im soldering all the PCB interconnections, alot of wiring left to do.

A lamp..not bad at all...im thinking....mabye i sould get a flexi pipe for the lamp

...gold coloured would be nice an old school.

hmm...how would i design such a lamp...i need it to be small...

..guess i'll have to sit down and design something.......yeah...the interconnections will have to wait.

Thanx!!! :D

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Im not too familliar with "Stryper", and believe me, it was never my intention

to make you all puke from looking at my beautyfull powercord. 8)

Nononono, I was puking from watching Stryper, I think your choice of power cord is awesome!

Shoulda made that more clear, grumble grumble...

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Thanx man! Yeah i love this powercord!

Im going to order more at payday, cuz theyre running out,

and they tell me that this cord will never be in stock again. :(

Is there any company that somone here knows about, that have more choices in dressed powercords?

Cuz other patterns, and collours would be sweet on my upcomming projects.

Oh yeah, im just curious.

How many current does a fully fitted MB64 draw with these new version PCB's?

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:)

Thanx for the tip Stryd-one!

Ok, so iv'e put the lamp design on halt and and have proceeded with wiring the DM.

Now this picture of the "starlike" pattern for the pots are confusing...

starlike_pot_wiring.jpg

Im allready having trouble separating Vs and Vd....

But if i solder the pots in this "starlike" pattern...then...Vd and Vs will be swiched on pots to the right..

Am i wrong...?

I though i was supposed to connect Vd and Vs in the same way on all pots..  ???

Could someone just clarify this for me please.

Counting the pins on the pots from left to right.

Pin1= Vs

Pin2= Din Signal (D0,D1,D2...)

Pin3= Vd

Is this correct?

<add-edit>

And also..

Wich one of these are right?

1. Vs= +, Vd= Ground

or

2. Vd= +, Vs= Ground

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But if i solder the pots in this "starlike" pattern...then...Vd and Vs will be swiched on pots to the right..

Am i wrong...?

I though i was supposed to connect Vd and Vs in the same way on all pots..  ???

You definitely should connect Vdd and Vss the same way on all pots.

The drawing has it wrong. I think the best way to go would be that:

Vdd (+) is at the clockwise extreme of the pot's travel, and

Vss (-) is at the Anti-clockwise extreme.

You can get it to work the other way, but you'll need to use scaling, and it's just not the right way to do it!!

- I've seen that drawing a few times in the past, and it seems it is a hasty sketch, intended mostly to show the star pattern, but generally ends up creating confusion about Vdd and Vss polarity!!

Wich one of these are right?

1. Vs= +, Vd= Ground

or

2. Vd= +, Vs= Ground

The second one is correct. Vdd is Positive (+5 Volts), Vss is negative. (0 Volts)

The terms themselves relate to their use with FET devices. (Perkaps a wiki entry would help?)

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Cool page that one. I just beefed it up a bit.... I'm sure there's a lot that we aren't thinking of.

I found that I could never remember what Vss/Vdd/Vlmnopq meant, until I learned what the abbreviations meant.:

Vcc - Collector

Vee - Emitter

Vdd - Drain

Vss - Source/Supply. Depends who you ask. (Buß.)

What are they talking about? Electrons, ie, negative charge.

HTH!

P.S. Is it poor form to quote your own post??

no

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This is soo frustrating.

The regulator on the core is running very hot.

You can smell the hot electronics like 30 sec's after turning it on.

Even now when i have removed power supply to the backlit LCD, it's still running hot.

I hoped it would fix it but it hasn't obviously..what to do now?  ???

This worries me alot, due to the small space inside that compartment.

Alot of cables running through there, and i don't want them scorched to death.

<edit>

Would this be due to the fact that im feeding the core with 9 volts?

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Err nah 7.5 technically speaking should not be enough - although it does work for nils, so datasheets are always approximate ;)

The same theory applies here as from this thread: Re: FM262 First DIY Project about your FM. Regulators need 2V and rectifier needs 1V, overhead of your 5V output, so we should have 8V minimum. I find that 8.6V is my magic number, I've had weird problems on anything less. 9V should be OK, but you don't wanna go much higher, and a heatsink is recommended - do you have one?

I'd start looking for shorts...

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If you have a 9v transformer, then the voltage  :P presented to the regulator is probably as high as

11 Volts.

Confused? Me too.

You produce 9V RMS from your transformer secondary coil (RMS is almost always used in AC measurement)

You then rectify this, and in the process lose 1.2V RMS, due to recifier voltage drop of 0.6V per diode.

You then filter this with large capacitors, essentially smoothing the peaks out, but the voltage these caps get to will be close to the peak-to peak voltage. (It won't be dead-on, for various reasons).

SO. A 9V transformer puts out around 9V RMS.

At the regulator this will be:

(9V - 1.2V) x (sqrt 2**= 1.414

7.8 x 1.414 = 11.03 Volts.

As I say, in practise the capacitors will reach an equilibrium of less than the p-p voltage from the rectifier.

Edit: And this voltage will depend on a number of factors, including current draw. /edit

But it will still be more than 9 volts.

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Yes i do have a heatsink on the core regulator, but it' is running really hot.

And i have measured the voltage comming in before the regulator and it is 9.10VDC.

Im going over everything today, hopefully i'll fix this soon.

Wont be easy, it's pretty full in there..

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Ok so i discovered something more.

My LCD wasn't displaying anything.

Iv'e desoldered it, resoldered it, ive tried connecting it both ways, mirrored

and unmirrored.

Regulator still getting hot.

So i opened up my MbSID (Darth vaders synth), i did this for curcuit reference, and i discovered that

iv'e conected the D3 (with the 1K pull up resistor) directly to J2 on the core in my DubMasta.

Now in my MbSID i didn't do this, i conected it directly to the +5VCD outlet on the PSU board.

And the regulator on the core in the MbSID is running cool.

I disconnected the LCD on my DubMasta again, and also disconnected the D3 from the J2 port on the core.

Regulator stoped running hot.

Looks like it's kinda solved....

But whould this really make the LCD NOT printing anything on the screen?  ???

<edit>

I was again wrong in my assumption.

Regulator is still getting very very hot, and my LCD wont desplay anything.

<edit>

there is definetly something wrong here.

Im reading low voltage (1,34VDC) on the output pin of the regulator.

Getting the same results when measuring port J2.

Must be a short somewhere.

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Yeah, this sounds a lot like you have a short somewhere in the LCD world.

Are you connecting to the core using a pin header? If so, that (pretty much) rules out issues at the core end.

So, in this case, you'd be wiring direct to the board at the LCD end?

Perhaps a photograph?

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Using no pin headers, they are just too expensive around here.

I solder directly to pins, just like on the MbSID i built.

I'll take a foto, even though it's not the most clean setup,  :-[

I can't find any short on the LCD though.

lcdconnections_01.jpg

lcdconnections_02.jpg

lcdconnections_03.jpg

lcdconnections_04.jpg

even though if there where a short on the LCD...would this make port J2 show 1.34VCD..

even when iv'e disconnected the D3 pin from port J2?

<edit>

This is not making any sence to me.

Im getting stable 9.20 volts in to the J1 port of the core.

I even unmounted the Core from the bottom of my DM and looked it over.

I cannot find any shorts anywhere on either bottom or topside.

Iv'e even tried resoldering power related components,

and im still getting 1.34 VDC out of the regulator on the core and it is running hot as hell!

I'll try to swap it for a new one, it might be broken o something.

Im starting to feel the crazy bug comming back...it's giving me chills... >:(

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