Master Section resistors

[Luba Dvorak]

Hello All, new here.

I have a 28ch 1988 Elan 

I'm currently re capping channels 17-28 as the previous ones were done by previous owner.

I took it apart to clean each channel strip. Replaced 1-16 and recapped ch17.

When I put ch 17 back in to the board to test I turned it on and saw some smoke coming out of the master section. Immediately turned it off but found I burnt out 4 resistors on the master section: R120,128,136,144. I believe this happened because i had plugged the ribbon cables 1,2,3 into the wrong slots. 

I took the master section out to replace the resistors but I'm finding the schematic calls for 47ohm resistors but the ones installed come up at 33ohms. A quick google search tells me thats how some of them came from the factory.

Any insight advice is appreciated. Images attached

Thanks in advance

[Luba Dvorak]

[David Iungerich]

I think if you match the burned out resistors to r119’s value that would keep the design as it was originally built 

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[Luba Dvorak]

Yes thanks. thats what I was thinking also, just curious why the difference in schematic vs pcb

[Mike S.]

Should be 47 ohms

Mike

On Wed, Jul 22, 2026 at 11:38 AM Luba Dvorak <lubad...@gmail.com> wrote:

Yes thanks. thats what I was thinking also, just curious why the difference in schematic vs pcb

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[Luba Dvorak]

If you look at R112 its 33ohm and the same as R120. Both of these call for a 47ohm on the schematic.

These are all factory

[Luba Dvorak]

Thanks Mike!

[David Iungerich]

I’ll make a guess … this looks like a voltage divider with one of two equal resistors in each leg while the next item in series is the 100k ohm pot controlling the overall amplitude/level of the signal.  If this is the case 14 ohms difference in the constant side might not make a significant difference electrically.

On Wed, Jul 22, 2026 at 11:38 AM Luba Dvorak <lubad...@gmail.com> wrote:

Yes thanks. thats what I was thinking also, just curious why the difference in schematic vs pcb

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[Mike S.]

But 33 ohms will be fine, Is only to prevent the Level pot  going too low or making noise.

The pots may have tens of ohms difference 5% of the 100K!

Sincerely

Mike Stoica

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