Sredna

Re: MK47 assembly - lots of pics
« Reply #40 on: November 01, 2010, 11:41:35 AM »
The U47N uses 2 X 8Hy.
Hmm... in which direction do the electrons actually go?


ioaudio

Re: MK47 assembly - lots of pics
« Reply #41 on: November 02, 2010, 08:30:14 AM »
I've been meaning to update the assembly instructions but could'nt get to it - i hopefully will get some spare time tonight.

tommypiper

Re: MK47 assembly - lots of pics
« Reply #42 on: November 02, 2010, 12:18:37 PM »
yes:
1. the choke helps filtering crap from the mains and is a better solution for "poluted" places.
2. unloaded voltage does'nt rise as high as with the resistor-only circuit.

-max



Is this referring to a PSU schematic or discussion that exists somewhere?  If so, can you point me to it, please?

Are there any PSU schematics or discussions for this project?  What kind of PS and voltage is needed for the relay?  Etc.
Imagine a wet, slightly chilled from its gas release and decompression, with water droplets condensing, sucking surface tension, slowly sliding down the side, capped by a healthy virgin froth on top..

zayance

Re: MK47 assembly - lots of pics
« Reply #43 on: November 02, 2010, 12:21:45 PM »
yes:
1. the choke helps filtering crap from the mains and is a better solution for "poluted" places.
2. unloaded voltage does'nt rise as high as with the resistor-only circuit.

-max



Is this referring to a PSU schematic or discussion that exists somewhere?  If so, can you point me to it, please?

Are there any PSU schematics or discussions for this project?  What kind of PS and voltage is needed for the relay?  Etc.

Speaking in base of this one i think:

http://www.groupdiy.com/index.php?topic=35667.220

ioaudio

Re: MK47 assembly - lots of pics
« Reply #44 on: November 02, 2010, 03:10:24 PM »
I just up-ed the PSU schematics to the first post.
Since the triad choke's are very cost-effective you can use two of them in series.

Skylar

Re: MK47 assembly - lots of pics
« Reply #45 on: November 03, 2010, 01:04:00 PM »
Thanks Max. I'm looking forward to getting mine built here pretty soon.
I will share photos when it's done.


This is also a test post, as I'm getting a database error when I try to post in the White Market.

horvitz

Re: MK47 assembly - lots of pics
« Reply #46 on: November 03, 2010, 02:20:35 PM »
Thanks for the updated drawing.  I'm actually working on my PSU layout right now, too.  A question on the 500R/5W trimmer.  Would something like one of those adjustable wirewound chassis mount things work here?  Like this:

http://www.mouser.com/ProductDetail/Ohmite/D25K500E/?qs=sGAEpiMZZMvNd0dY0KymzrlSPm%2fRXd%252bpQI%252bBTbFMc34%3d

I'd certainly prefer something pcb mountable, but I'm not seeing anything like that in the 5W+ range.

  Brian


Kingston

Re: MK47 assembly - lots of pics
« Reply #47 on: November 03, 2010, 02:31:44 PM »
Thanks for the updated drawing.  I'm actually working on my PSU layout right now, too.  A question on the 500R/5W trimmer.  Would something like one of those adjustable wirewound chassis mount things work here?  Like this:

http://www.mouser.com/ProductDetail/Ohmite/D25K500E/?qs=sGAEpiMZZMvNd0dY0KymzrlSPm%2fRXd%252bpQI%252bBTbFMc34%3d

I'd certainly prefer something pcb mountable, but I'm not seeing anything like that in the 5W+ range.

  Brian



smaller, cheaper:

http://fi.mouser.com/ProductDetail/Alpha-Taiwan/VW24F-10-195K-B1K/?qs=sGAEpiMZZMtxdMMi52izynF7ZLtMY%252bzpmAcDgBFEwt4%3d

can be easily modified to be PCB mountable. Not 500ohm, but 1K. It's close enough for this task, and accuracy won't suffer. I've used them for this exact task in the past and they work well.
« Last Edit: November 03, 2010, 02:33:19 PM by Kingston »

horvitz

Re: MK47 assembly - lots of pics
« Reply #48 on: November 03, 2010, 02:41:50 PM »
Ahh.  Good idea with the pot, Kingston.  Thanks.

Matthew Jacobs

Re: MK47 assembly - lots of pics
« Reply #49 on: November 04, 2010, 06:59:38 AM »
Talking about PSU... I wanna build mine out of wood...

Any things I got to watch out for? Should I line the interior in metal? to protect against hum, fire, health and safety, etc?

JD


Kingston

Re: MK47 assembly - lots of pics
« Reply #50 on: November 04, 2010, 07:14:38 AM »
Should I line the interior in metal?

Yes.

consider wood a decoration only. You still need a fully enclosed metal case inside for electrical safety, and for shielding electromagnetic and especially radio frequency fields.

Matthew Jacobs

Re: MK47 assembly - lots of pics
« Reply #51 on: November 04, 2010, 07:31:12 AM »
Thanks Kingston  :)

horvitz

Re: MK47 assembly - lots of pics
« Reply #52 on: November 04, 2010, 09:40:28 AM »
As much as I don't like their stuff, Hammond has some wood bracketed metal cases now.. At least from the pictures, they don't look too bad.

ioaudio

Re: MK47 assembly - more pics added
« Reply #53 on: November 04, 2010, 02:49:16 PM »
Pictures for the constuction / heat transfer added.

baadc0de

Re: MK47 assembly - more pics added
« Reply #54 on: November 04, 2010, 04:44:29 PM »
FWIW, UPS and FedEx can have nasty "duty handling fee" surcharges into europe, never had these problems with USPS.

Denyle Guitars

Re: MK47 assembly - more pics added
« Reply #55 on: November 12, 2010, 10:15:11 AM »
Anyone know the min diameter for the mic body?

tommypiper

Re: MK47 assembly - more pics added
« Reply #56 on: November 12, 2010, 12:49:53 PM »
Max, thanks for the PSU schematic.  Can you please explain the test switch, and the pattern switch on that schematic?  How will patterns be selected, and which patterns?  What is the test switch?

Also, I don't understand the two parrallel resistors, 680 and 330.

Finally, the 500R pot?  Is that simply to adjust the 105v?

Thanks.
« Last Edit: November 12, 2010, 12:51:31 PM by tommypiper »
Imagine a wet, slightly chilled from its gas release and decompression, with water droplets condensing, sucking surface tension, slowly sliding down the side, capped by a healthy virgin froth on top..

Re: MK47 assembly - more pics added
« Reply #57 on: November 12, 2010, 12:54:21 PM »
FWIW, UPS and FedEx can have nasty "duty handling fee" surcharges into europe, never had these problems with USPS.

not to mention that they're outrageously more expensive (2-3x cost) than usps for international.
There's nothing like the right tool for the job.
And -usually- that's what I end up using...
..nothing like the right tool for the job!

ioaudio

Re: MK47 assembly - more pics added
« Reply #58 on: November 12, 2010, 01:26:17 PM »
tommy,

the test switch connects a test-load to check the ballbark - voltage before connecting the mic to the psu.
the 680 330 resistor is either / or - to pre-adjust the voltage depending on your mains transformer's output.
500R is for final adjustments.

Patterns are like on a original U47 - omni and cardioid - switched via relais. The actual pattern switch is located in the PSU.

-max

nashkato

Re: MK47 assembly - more pics added
« Reply #59 on: November 12, 2010, 01:31:37 PM »
Quote
   Anyone know the min diameter for the mic body?

im going to go with 50mm diameter , cause thats what i have got anyway.
i put the assembled pcb in to check if it might fit , and yes , though theres not much of a space left.


 

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