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January 17, 2020, 08:51:08 AM

Author Topic: Eros 2 schematic and manual  (Read 138 times)

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Offline feras

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Eros 2 schematic and manual
« on: December 23, 2019, 11:54:59 AM »
I assembled Eros2. It works fine. I noticed 1 mismatch between the provided schematic (page 7 manual) and provided assembly instructions. In the schematic EF86 point A6/B6 is connected to C4S OB point and resistor 90R9 which goes to 7308's C2/C7.

In the instruction manual a 90R( resistor is connected between A6/B6 and 9/10 or 14/5. From 9/10 and 14/15 is connection to C4S and trough one more 90R9 resistor to C2/C7.
In the schematic option signal goes from EF86 to 7308 though one 90R9, but according to the assembly instructions via 2 resistors.

Which option is correct? I tried both and have no preference for sound.

Thanks

Offline Paul Birkeland

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Re: Eros 2 schematic and manual
« Reply #1 on: December 23, 2019, 12:30:51 PM »
In the schematic EF86 point A6/B6 is connected to C4S OB point and resistor 90R9 which goes to 7308's C2/C7.

In the instruction manual a 90R( resistor is connected between A6/B6 and 9/10 or 14/5. From 9/10 and 14/15 is connection to C4S and trough one more 90R9 resistor to C2/C7.
The manual does not have the plate stoppers for the EF86 because they are not absolutely necessary.  They are certainly not harmful, and since they made the build a bit easier to do, we opted to include them.

Which option is correct? I tried both and have no preference for sound.
It's very unlikely that you'll hear any difference between the configurations.  I would leave them in personally, but then again I'm the one who put them there in the first place...
Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man

Offline feras

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Re: Eros 2 schematic and manual
« Reply #2 on: December 23, 2019, 07:54:45 PM »
Thank you for the response.

Offline grufti

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Re: Eros 2 schematic and manual
« Reply #3 on: December 23, 2019, 09:22:10 PM »
Theoretically those resistors add a tiny bit of noise, but I have them in my Eros 2 also.

Offline Paul Birkeland

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Re: Eros 2 schematic and manual
« Reply #4 on: December 24, 2019, 05:57:15 AM »
Theoretically those resistors add a tiny bit of noise
Or they prevent a tiny bit of oscillation ;)
Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man