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Old 19th January 2004, 01:35 PM   #1
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Well I'm done with my first gainclone with the exception of a front panel. I put up some pics and details here. It's nothing fancy, but it sounds pretty darn good. I can see why people making the super tricked out ones are so happy with theirs.
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Old 19th January 2004, 02:36 PM   #2
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Hi Dustin,

Can you post your pics here?
Your link is "temporarily unavailable" due to excessive data transfer...
That's what happens when you open a thread here.
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Old 19th January 2004, 05:00 PM   #3
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Well I guess you get what you pay for with free sites huh? Sorry about that. I didn't want to use up the space here, but I'll post a couple of the pics.

Here's one of the chips, LM1875, 220k feedback, 10k input resistors, .1uF across ps pins, 47uF input cap all from the Shack.
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Old 19th January 2004, 05:02 PM   #4
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Here's a shot of the heatsinks, no laughing I realize they aren't straight
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Old 19th January 2004, 05:07 PM   #5
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Here's the inside of the chassis, transformer is from ApexJr. It's a Torroid Tech 1010VA I wired the primaries in series to get half the usual secondary voltage, after recifiers (MUR860) and ps caps (1000uF Panasonic FC) I have +/-22.5DC rails. The chassis is from a broken RCA tape deck I got at the Radioshack outlet here in Charleston for $5.
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Old 19th January 2004, 05:10 PM   #6
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There's quite a few more pics on the website, I don't want to post too much here. I'm quite happy with it, I just need to figure out how I want to finish the front and get rid of the slight hum and it's done.
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Old 19th January 2004, 07:07 PM   #7
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impressed and my guess is that the humm will disappear when you doublecheck both loops (ground and earth and see if the 0 from the transformer is connected to the ground loop as well....

Jean-Pierre

seems like you know how to use "minimalistic' approach!
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Old 19th January 2004, 07:55 PM   #8
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Thanks for the pics!
Just think!...you can only make it better from here on in...you have passed the first mildstone on building it...now the fun part is tweaking it to death!!!..hahaha


DIRT®
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Old 19th January 2004, 08:52 PM   #9
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Thanks guys, I definately plan on messing with it some from here. I already have two more channels sitting on my computer desk waiting to be put in, eventually I'd like to make it a five channel. For now though I'm happy to be sitting here listening to it!!
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Old 20th January 2004, 08:40 AM   #10
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Dustin,
Very nice.

But...
You need some PSU bypass caps on the chip's pins, because the caps are very far away.
100uf will do.
The way you have it I don't see another choice.
Solder the caps direcly to the LM1875s (+ and -), and join the grounds of the two channels (you can do it with the caps' legs).
From a midle point of that, make it the power ground.
No more hummmmmmm.
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