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May 20, 2022, 11:39:44 PM

Author Topic: Measuring voltages while playing a 60 Hz sine wave. [resolved]  (Read 1672 times)

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Offline Colonl_Charisma

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Re: Measuring voltages while playing a 60 Hz sine wave. [resolved]
« Reply #45 on: August 17, 2021, 10:41:16 AM »
Thanks! What kind of wires do you use for the Crack? I would like to pick up some extra to have on deck.

I’ll get those ordered, and I guess we can come back to the wiring once everything arrives.

edit:

Are these 100K resistors fine?

https://www.mouser.com/ProductDetail/Vishay-Dale/CCF02100KJKE36?qs=sGAEpiMZZMsPqMdJzcrNwncUUYJvQsyPlLH02FNSk8g%3D
« Last Edit: August 17, 2021, 01:39:26 PM by Colonl_Charisma »
Ross

Offline Paul Birkeland

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Re: Measuring voltages while playing a 60 Hz sine wave. [resolved]
« Reply #46 on: August 18, 2021, 07:01:23 AM »
You want 20-22 gauge solid core tinned copper wire.  Be sure it's tinned and be sure it's not stranded.
Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man

Offline Colonl_Charisma

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Re: Measuring voltages while playing a 60 Hz sine wave. [resolved]
« Reply #47 on: August 18, 2021, 07:33:19 AM »
Thanks for the info, PB. I will be sure to order that type of wire.

How do those resistors look? Does the power rating or tolerance matter for what I will be doing?
Ross

Offline Paul Birkeland

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Re: Measuring voltages while playing a 60 Hz sine wave. [resolved]
« Reply #48 on: August 18, 2021, 09:23:17 AM »
Sorry, you want 33K resistors.

I would not use 2W resistors in that position, that's overkill and just too big in general.
Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man

Offline Colonl_Charisma

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Re: Measuring voltages while playing a 60 Hz sine wave. [resolved]
« Reply #49 on: August 18, 2021, 02:32:42 PM »
All good! I actually have two 33K resistors that are 1/8 W. I used these on my volume pot to pad it.
Ross

Offline Paul Birkeland

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Re: Measuring voltages while playing a 60 Hz sine wave. [resolved]
« Reply #50 on: August 18, 2021, 02:51:18 PM »
If you're ordering a pot, I would order more.  It helps if they are a bit longer.
Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man

Offline Colonl_Charisma

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Re: Measuring voltages while playing a 60 Hz sine wave. [resolved]
« Reply #51 on: August 18, 2021, 03:14:12 PM »
Will do! I'll get all this ordered tonight.
Ross

Offline Colonl_Charisma

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Re: Measuring voltages while playing a 60 Hz sine wave. [resolved]
« Reply #52 on: August 21, 2021, 01:56:57 PM »
I should have everything in on Monday. How close should the balance pot be to the volume pot? I am going to go ahead and drill a hole in the chassis for the new pot.
Ross

Offline Paul Birkeland

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Re: Measuring voltages while playing a 60 Hz sine wave. [resolved]
« Reply #53 on: August 21, 2021, 04:38:03 PM »
2"-3" is about enough.

I've made a crude image that shows the proper perspective if you're looking from the back of the chassis.  Be sure this is adequately clear before drilling holes or anything.
Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man

Offline Colonl_Charisma

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Re: Measuring voltages while playing a 60 Hz sine wave. [resolved]
« Reply #54 on: August 22, 2021, 08:04:29 AM »
Thanks, PB! Should I desolder all of the old wire, or could I just clip the wires that I currently have and reattach them to the balance pot?
Ross

Offline Paul Birkeland

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Re: Measuring voltages while playing a 60 Hz sine wave. [resolved]
« Reply #55 on: August 22, 2021, 08:46:16 AM »
That is up to you.  I've never done what you're doing, so you'll have to slog through it and figure some of this out on your own.
Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man

Offline Colonl_Charisma

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Re: Measuring voltages while playing a 60 Hz sine wave. [resolved]
« Reply #56 on: August 22, 2021, 01:00:41 PM »
No problem. This will be an interesting experiment haha. I do have my extra wire (and plenty of it), so if I need to redo my wiring it shouldn’t be a problem.

As far as the actual wiring goes, left and right rca jacks to the balance pot, and the balance pot to the volume pot, what is that looking like? Or is that something we will need to work through?

I really appreciate your help.
Ross

Offline Karl5150

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Re: Measuring voltages while playing a 60 Hz sine wave. [resolved]
« Reply #57 on: August 23, 2021, 03:02:47 AM »
Ross,
If space is tight and you haven't drilled yet, I was able to get the CtoC on the Vol/Bal pots down to 1.75" as per the photo Paul  attached and 1.5" sitting side by side with the terminals pointing to the same side. 
Another simple fix for the imbalance is dual-mono volume pots.
Good luck on your mods,
Karl
Karl
Downstairs: Planar3>Eros>Stereomour II>diy OB Betsy+
Upstairs: DIY RP1>Reduction / CD5004>Seductor/SEX 3.1.1>FH3/DT770 pro/HE-4xx
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Offline Colonl_Charisma

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Re: Measuring voltages while playing a 60 Hz sine wave. [resolved]
« Reply #58 on: August 23, 2021, 08:45:46 AM »
Hi Karl,

I have not done any drilling yet. Would you mind posting a pic of your build? I'd like to see a longview of the wiring. The closeup view that Paul provided helps a lot, but I'd like to see the full view (I also realize that Paul's pic is not a Crack so a larger view of that one would probably not help me out much).

I appreciate the kind words! I believe this mod will go smoothly once I get going.
Ross

Offline Colonl_Charisma

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Re: Measuring voltages while playing a 60 Hz sine wave. [resolved]
« Reply #59 on: August 25, 2021, 07:53:46 AM »
I got my holes drilled and my new potentiometer place inside my Crack. So far, so good. I am going to solder the connections as they are shown in the above image. I'll also try to post some pics later tonight of how it is looking after I solder the connections.
Ross