VintageWindings Pultec Document - Possible Error. Rotary Clarification Needed.

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AllMixedUp

Well-known member
Joined
Nov 15, 2020
Messages
46
First of all, I am unsure if I should put this here or in the filter section, so my apologies if this is the wrong area of the forum.

I am currently building a solid state Pultec based around the VintageWindings.com documentation found on the website (link below).  The only things I have left to buy are the rotary switches and the filter units he provides (as soon as funds allow).  I ran across a possible issue - either in their documentation or my understanding of it - and was hoping one of you would be able to provide some clarification.  I have also sent an email to the contact email on the site but have yet to receive a response.

It is my understanding that "Make Before Break" rotary switches are shorting, and "Break Before Make" are non-shorting.  In the documentation (pg. 10) it specifies that you need to use "Make Before Break" switches to avoid any audible clicking when changing frequencies.  However the part numbers given for each rotary switch are for the non-shorting (Break Before Make) variety according to the datasheets found on Mouser.  The part numbers for the elctroswitch rotary switches he recommends are listed (pg. 11) as follows:

C4D0112N-A
C4D0212N-A

Are these the correct part numbers or should I replace those part numbers with the shorting variety listed below:

C4D0112S-A
C4D0212S-A

I am unsure if the error is in the part numbers, or if I am in fact suppose to be using BBM rather than the document specified MBB.  Any help on this matter would be greatly appreciated.

Link to said documentation: http://vintagewindings.com/tech%20swag/Pultec%20EQP-1A3%20DIY.pdf


 
Here is an image with info from the VintageWindings PDF as well as a shot of the part numbers and specifications from the Mouser PDF.  I hope this helps if my question above wasn't quite clear.
gMM1DPR.jpg


 
abbey road d enfer said:
I believe you are correct. The reference of teh proposed switches is for non-shorting types.
You need to resolve this issue with the seller.

Thanks for the response.  I was finally able to reach the seller.  He said for sure that you want to use shorting switches. 
 
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