Mark IIC (not IIC+) draft schematic

Mark I's, II's, III's and the almight IV

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chipaudette
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Re: Mark IIC (not IIC+) draft schematic

Post by chipaudette » Mon Jul 13, 2009 6:42 am

Hi Again,

I opened up the amp AGAIN. I confirmed the 750p value on the treble shift by looking at it. I also corrected a few other values...

Mark IIC, Schematic V1.2:
http://picasaweb.google.com/lh/photo/yG ... directlink

I also mapped out most of the EQ circuit and most of the power amp circuit. I'll draw that up this week.

Thanks for your interest!

Chip

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jvk
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Re: Mark IIC (not IIC+) draft schematic

Post by jvk » Mon Jul 27, 2009 12:06 am

Hello gentlemen. Here you go:

IIC+ pcb bottom
Image

Word of caution... the level of butchery that I've performed here should only be practiced if you don't mind sacrificing the amp (partly at least), because you would be desoldering, cutting wires and/or damaging the pcb traces (amazing how easy the traces come off) on a 25 year old relic :)

All the best
Jonny
Last edited by jvk on Mon Jul 27, 2009 10:28 am, edited 1 time in total.

chipaudette
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Re: Mark IIC (not IIC+) draft schematic

Post by chipaudette » Mon Jul 27, 2009 5:44 am

Hi Johnny,

Thanks so much for posting this pic. Unfortunately, when I click on it, I get an error from google...

The requested URL /_o912b1uGg_c/Sm0y8oTmN7I/AAAAAAAAABA/r2By-2Y06Q4/DSC02855.JPG was not found on this server.

Could you re-check your link? I'm dying to see the pic!

Thanks,

Chip

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jvk
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Re: Mark IIC (not IIC+) draft schematic

Post by jvk » Mon Jul 27, 2009 10:30 am

The link should be fixed now.

chipaudette
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Re: Mark IIC (not IIC+) draft schematic

Post by chipaudette » Sun Apr 29, 2012 9:12 pm

Hi All,

To anyone who still cares, I got a PM asking about my IIC (not IIC+) schematic. So, I dug it out again and saw that I had updated it without uploading it. So, if you want the latest version, the link is below. Note that there is now a page 1 (preamp) and a page 2 (power amp, EQ and a partial schem for the power supply). Enjoy!

Page 1: https://picasaweb.google.com/lh/photo/6 ... directlink

Page 2: https://picasaweb.google.com/lh/photo/9 ... directlink

Gallery: https://picasaweb.google.com/lh/photo/6 ... directlink



Chip

Thermionc-Apocalypse
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Re: Mark IIC (not IIC+) draft schematic

Post by Thermionc-Apocalypse » Thu Aug 08, 2019 2:10 am

Chip, sadly the links with all your hard work are dead.

Do you think it might work better to attach them to a reply rather than using fickle external hosts?

jrb32
Mark III
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Re: Mark IIC (not IIC+) draft schematic

Post by jrb32 » Thu Nov 14, 2019 7:37 am

RP10 IIC Schematic: https://drive.google.com/open?id=1mpJFs ... 81rlggkt6M
RP10 IIC Board View: https://drive.google.com/open?id=1Lx0Ao ... V5IgEUf5cS

RP11A IIC Schematic: https://drive.google.com/open?id=1_KWgn ... l8qHdo5nji
RP11A IIC Layout : https://drive.google.com/open?id=1CALq ... 8LQ627h54b

Based these on chipaudettes originals and expanded when I traced my RP10 IIC (original) fully. The RP11 is based off research but should be pretty much there 100%.

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jvk
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Re: Mark IIC (not IIC+) draft schematic

Post by jvk » Thu Nov 14, 2019 3:58 pm

Hi, that schematic contains the same error in the switching circuit that was present in the original Mesa schems. Here's the actual circuit: (I've traced more than one 2C, a 2C+ and also MKIVB)

https://drive.google.com/file/d/1yHC65i ... sp=sharing

Cheers
Last edited by jvk on Thu Nov 14, 2019 4:49 pm, edited 1 time in total.

jrb32
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Re: Mark IIC (not IIC+) draft schematic

Post by jrb32 » Thu Nov 14, 2019 4:41 pm

jvk wrote:
Thu Nov 14, 2019 3:58 pm
Hi, that schematic contains the same error in the switching circuit that was present in the original Mesa schems. Here's the actual circuit: (I've traced more than one 2C, a 2C+ and also MKIVB)

Image

Cheers
AMAZING! Could you make sure the picture is given permission to view as it's not showing up (error 403), or alternatively use something like https://imgbb.com/ to upload.

Many thanks in advance!!

jrb32
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Re: Mark IIC (not IIC+) draft schematic

Post by jrb32 » Thu Nov 14, 2019 4:43 pm

Also if you still have that picture of the bottom of the IIC+ PCB you could upload in a similar way I could kiss you right now! :lol:

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jvk
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Re: Mark IIC (not IIC+) draft schematic

Post by jvk » Thu Nov 14, 2019 4:50 pm

jrb32 wrote:
Thu Nov 14, 2019 4:41 pm
jvk wrote:
Thu Nov 14, 2019 3:58 pm
Hi, that schematic contains the same error in the switching circuit that was present in the original Mesa schems. Here's the actual circuit: (I've traced more than one 2C, a 2C+ and also MKIVB)

Image

Cheers
AMAZING! Could you make sure the picture is given permission to view as it's not showing up (error 403), or alternatively use something like https://imgbb.com/ to upload.

Many thanks in advance!!
:arrow: Post Updated

jrb32
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Re: Mark IIC (not IIC+) draft schematic

Post by jrb32 » Mon Nov 18, 2019 3:24 pm

Thanks a lot I'll update that switching part on the schematic. Cheers :D

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