Correct video pot for apple-1

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Joined: Nov 20 2004 - 00:26
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Correct video pot for apple-1

Please see the attached photo.
After considerable searching, and chasing false leads, I believe that the 100 ohm
trimmer pot on the left is the correct video pot for an NTI Apple-1 board.
I hope it is, as I had to purchase 20 !!.
(The most irritating false lead was an ebay seller, incorrectly claiming that
his Helitrim 100 ohm pots were correct for an Apple-1)

The photos of an apple-1 NTI board that I have are not that clear.

Can anyone confirm that the pot on the left is the correct pot please?

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Joined: May 30 2019 - 00:29
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This question is something I

This question is something I had to face (since I am building a NTI replica). The potmeter I have ordered is a spectrol 75H501 since I could not find the correct one (75H101). The 501 is a 500Ohm version instead of the normal 100Ohm. You sometimes find the 75RH101 specified as 75H101. The correct one does not seem have a black round base, only white with a metal cap:

 

This is what I have been able to see from the NTI pictures online. If someone has different information on this, please inform. 

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Joined: Apr 2 2015 - 11:46
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Video pot for Apple I

I have several Helitrim 100 ohm round pots with the black trim stem.  They look identical to what is in one picture of an original Apple I.  I also have a purple ceramic with gold top house numbered 6820 from Motorola that came to me in an AIM-65 display module that normally used the 6520.  It worked just fine in that application.  I have several Intel 3621 PROMs that are 256x4 T/S and some 3622 512x4 T/S that I'm trying to get programmed to the Apple I code.  If anyone has any interest in any of these, please send me a PM.

 Dave

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Can you post a pic of the

Can you post a pic of the Helitrim pot? Looking at pictures of my original NTI board the pot is all white I don’t see any black.  I actually checked all my pictures of various NTI boards also.  I was planning a visit to my board this weekend at the bank, I will triple check this in person.  

 

Cheers,

Corey 

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helipot
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Apple video trim pot?

This is the trim pot I have several of in both tinned and gold plated leads 100 ohm.

 

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Last seen: 1 day 17 hours ago
Joined: May 30 2019 - 00:29
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Well, I cut out the

Well, I cut out the potentiometer part from several NTI Apple pictures in the registry (London Science museum, Bern, Dinxdof, Living computers +), and they all show a potentiometer with a white base and white screw. It has a metal ring around the top with a metal notch like the 75H101:

 

 

I haven't been able to find any original NTI boards with the Helix potentiometer (but they do look nice). Which Apple 1 did you seen it on?

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