madbeanpedals::forum

Projects => General Questions => Topic started by: aballen on March 09, 2013, 01:48:57 PM

Title: Cascading MN3008 to get MN3005
Post by: aballen on March 09, 2013, 01:48:57 PM
I found a great layout on small bear for cascading "fake MN3005" to get the delay of an MN3005 .  Don't get me wrong, smallbear is great, and I trust they work as advertized, but there is really no way of knowing what they are.

I'm wondering if I could use this same schematic and parts to cascade authentic MN3008 and get the equivalent of MN3005 delay times for an aquaboy build.

Not cheap, but I really want warm, clean, long repeats.. and with the added headroom, I would put a road rage in there to run it at 18V.

I'm just dying to do an aquaboy build, but I'm not going to do it if I cant do it "right".

Title: Re: Cascading MN3008 to get MN3005
Post by: midwayfair on March 09, 2013, 04:09:45 PM
Quote from: aballen on March 09, 2013, 01:48:57 PMDon't get me wrong, smallbear is great, and I trust they work as advertized, but there is really no way of knowing what they are.

Actually, there's a very good way to tell what they are: You plug them into a delay built for MN3005s and get exactly half the expected delay time.

There aren't other chips that would work in that situation. Steve at Smallbear knows his stuff. If he says they're MN3008s, they are, unless someone has gone through an extraordinary amount of effort to build an exact clone of the MN3008, in which case ... it's an exact work alike and might as well be a 3008.
Title: Re: Cascading MN3008 to get MN3005
Post by: jkokura on March 09, 2013, 04:16:08 PM
Yeah, the fake MN3005's from Smallbear are MN3008s. They're the same as other MN3008. You don't need to treat or think of them differently.

Jacob
Title: Re: Cascading MN3008 to get MN3005
Post by: aballen on March 10, 2013, 02:03:28 PM
Ok then I'm doing this for my aquaboy!  I was concerned they might actually be V3205s or something like that.
Title: Re: Cascading MN3008 to get MN3005
Post by: Haberdasher on March 10, 2013, 03:17:48 PM
Is there any reason one couldn't use the dbl dlay pcbs from the aquaboy 2012 project for cascading these?
Title: Re: Cascading MN3008 to get MN3005
Post by: jkokura on March 10, 2013, 05:26:08 PM
No reason. They are essentially the same.

Jacob
Title: Re: Re: Cascading MN3008 to get MN3005
Post by: aballen on March 11, 2013, 01:36:52 AM
Ok, I searched, but can't find it.  Anyone for a link to the 2012 pdf with the layouts?

I'm going to use whichever is more compact.
Title: Re: Cascading MN3008 to get MN3005
Post by: chordball on March 11, 2013, 02:10:30 AM
Check the bottom of the first post for the file.
Title: Re: Cascading MN3008 to get MN3005
Post by: jimilee on May 02, 2013, 04:52:18 AM
So can I use the 3008 in place of the 3005 for my abdx build or do i need to do something special? Am I only going to get half the delay time?
Title: Re: Cascading MN3008 to get MN3005
Post by: Scruffie on May 02, 2013, 04:57:01 AM
Quote from: jimilee on May 02, 2013, 04:52:18 AM
So can I use the 3008 in place of the 3005 for my abdx build or do i need to do something special? Am I only going to get half the delay time?

Nothing special to do, they're drop in for each other and half the buckets, half the delay time... well basically.

So yeah, you'll get 300mS...ish out of 2 MN3008 instead of 550mS...ish out of 2 MN3005.

Oh! You might have to play with the clock timing capacitor, I can't remember the DM-2 topology from memory, does it have a clock trimmer? If so, nothing special no.
Title: Re: Cascading MN3008 to get MN3005
Post by: aballen on May 02, 2013, 07:11:38 PM
Jimi, I you want a couple of these BBD doubler boards I made, I can send you two at cost.  I have too many anyway.  I should have them this week, and honestly I would love it if I could get a confirmation from someone else that I got it right.

Quote from: jimilee on May 02, 2013, 04:52:18 AM
So can I use the 3008 in place of the 3005 for my abdx build or do i need to do something special? Am I only going to get half the delay time?

Title: Re: Re: Re: Cascading MN3008 to get MN3005
Post by: jimilee on May 02, 2013, 07:12:46 PM
Quote from: aballen on May 02, 2013, 07:11:38 PM
Jimi, I you want a couple of these BBD doubler boards I made, I can send you two at cost.  I have too many anyway.  I should have them this week, and honestly I would love it if I could get a confirmation from someone else that I got it right.

Quote from: jimilee on May 02, 2013, 04:52:18 AM
So can I use the 3008 in place of the 3005 for my abdx build or do i need to do something special? Am I only going to get half the delay time?

sure, that'd be great! You still have my info?
Title: Re: Cascading MN3008 to get MN3005
Post by: DutchMF on May 02, 2013, 07:33:05 PM
Quote from: aballen on May 02, 2013, 07:11:38 PM
Jimi, I you want a couple of these BBD doubler boards I made, I can send you two at cost.  I have too many anyway.  I should have them this week, and honestly I would love it if I could get a confirmation from someone else that I got it right.

Quote from: jimilee on May 02, 2013, 04:52:18 AM
So can I use the 3008 in place of the 3005 for my abdx build or do i need to do something special? Am I only going to get half the delay time?


Do you ship international? I'd love 2 of those as well! Oh, and your moving avatar makes our cat completely crazy! She likes to sit with me when I'm on my laptop, and when your avatar comes on, damn! Sorry for the derail......

Another point: I'm not questioning SB (no experience with them myself, heard plenty of good feedback) but if the MN3005 fakes are basically MN3008's, why does a tested pair of them cost $15.95 when a single  real MN3008 is $14.95? Makes no sense to me....

Paul
Title: Re: Cascading MN3008 to get MN3005
Post by: aballen on May 02, 2013, 07:35:48 PM
I think it is basically because they are mis-labeled.  Its a good deal.  I bought 4.
Title: Re: Cascading MN3008 to get MN3005
Post by: aballen on May 02, 2013, 07:53:31 PM
I just checked shipping and apparently they are in my mailbox.

Jimi, I'll have to check for your info.  I'll let you know.

Dutch, I can ship to you, but I might need an extra euro for the international ship.  I'll check on that.  Also you should see my avatar on a white background, most people are really freaked out the first time they see it, they think its real. :D




Title: Re: Cascading MN3008 to get MN3005
Post by: DutchMF on May 02, 2013, 08:11:42 PM
Quote from: aballen on May 02, 2013, 07:53:31 PM
I just checked shipping and apparently they are in my mailbox.

Jimi, I'll have to check for your info.  I'll let you know.

Dutch, I can ship to you, but I might need an extra euro for the international ship.  I'll check on that.  Also you should see my avatar on a white background, most people are really freaked out the first time they see it, they think its real. :D

Cool stuff aballen, the extra Euro (or two/three) is no problem, keep me posted! I'll refrain from showing your avatar on a white background to Willem (our cat, short for Wilhelmina), might cost me a screen.... Thanx in advance dude, this might be a cool addition to my ABDX build!

Paul