Audio or Linear Tapered Potentiometers in the HDR?

FarOutThere

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I measured the pots in my old HDR, and as best I can tell they appear to be audio tapered in their resistance.



Fluxcap.com also shows, under the parts list, 100k Audio tapered, although mine have 50k.
HDR Parts List

Does anyone know if there is reasoning behind why Audio tapered pots are used in the HDR?
Are they known to be much preferred?
 

HDRKID

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I prefer using linear tapered potentiometers in mine. It makes getting a stick reaction easier.

Steven Gibbs originally was using 75K military-grade pots, but I need to call him up. Ask him about the differences. He did tell me not to use 10K pots. I like the linear tapered 100K potentiometers from Radio Shack, they are out of stock now. However, there are plenty of them on eBay that we can use.

100K-Ohm Linear-Taper Potentiometer (radioshack.com)

 

FarOutThere

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Thanks HDRKID (y)

RadioShack seems to be undergoing some sort of restructuring. Hopefully more parts see better availability ASAP.

It's expensive ordering specific small parts from overseas, shipping is the main cost. So I end up buying in larger numbers while I'm at it. Everything seems more expensive than it used to.

I'm still deciding what pots to use.

By the way does anyone know what shaft length the pots should have?
 

TimeFlipper

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Thanks HDRKID p

RadioShack seems to be undergoing some sort of restructuring. Hopefully more parts see better availability ASAP.

It's expensive ordering specific small parts from overseas, shipping is the main cost. So I end up buying in larger numbers while I'm at it. Everything seems more expensive than it used to.

I'm still deciding what pots to use.

By the way does anyone know what shaft length the pots should have?
The shaft lengths are made long to begin with to make room for Pots to fit inside whatever size of box they sit in...Most Pot shafts are "cut down to size" when in radios or HDRs because you don't need or want a long shaft projecting from a radio or an HDR, it would look unsightly and silly and could easily break off if handled incorrectly or you dropped the HDR..

HDRKID already told you he used a Linear Pot, but you will find in most HDR schematics that they use a logarithmic (Log) type pot...
There are only linear and log types of potentiometers...In an old radio the volume control is a Log Pot, and the Tone Control would be a Linear Pot...Try both type of Pots if you are unsure, then choose the one that gives you the best stick response...

HDRKID said Steven Gibbs used "Military Grade Pots" in his own HDRs...Those type of Pots have a very high degree of accuracy when quoting their resistance value...For example, most standard Pots that quote 50k resistance might only be about 49k or 51k resistance, but the Military Grade Pots would be exactly 50k resistance, and obviously be costlier..
 
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FarOutThere

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The pots Gibbs put into my HDR say ALPHA B50K
They don't look different to regular pots! Although testing them with a multimeter did give me pretty spot on 50K resistance.

Hoping to find some identical pots.

These ones look visually identical, and are available in the 50K for both log and linear, but the shaft length is only 8mm.

 

TimeFlipper

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The pots Gibbs put into my HDR say ALPHA B50K
They don't look different to regular pots! Although testing them with a multimeter did give me pretty spot on 50K resistance.

Hoping to find some identical pots.

These ones look visually identical, and are available in the 50K for both log and linear, but the shaft length is only 8mm.

Why not consider using a Pot that has more than 8mm spindle length?...There are lots of them out there, and you might get lucky again and find a 50k Pot that IS actually 50k...Don't try to overcomplicate simple matters :D..
 

FarOutThere

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Why not consider using a Pot that has more than 8mm spindle length?...There are lots of them out there, and you might get lucky again and find a 50k Pot that IS actually 50k...Don't try to overcomplicate simple matters :D..
I understand, however I want to recreate the classic HDR perfectly, and so every component is over-complicated and over-priced. :p

Shortly I will try to de-knob my HDR to get a better look at the shaft.
 

TimeFlipper

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I understand, however I want to recreate the classic HDR perfectly, and so every component is over-complicated and over-priced. :p

Shortly I will try to de-knob my HDR to get a better look at the shaft.
If you are attempting to recreate the Steven Gibbs classic HDR, I believe you will fail...All of the HDRs built by Gibbs are supposed to contain his very own "psychic signature" within them, that nobody can emulate :(..

All you have to do to remove the knob from the HDR, is to find the correct screwdriver and unwind the screw that clamps onto the Pots shaft, then lift the knob off, hardly rocket science :D..
 

FarOutThere

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If you are attempting to recreate the Steven Gibbs classic HDR, I believe you will fail...All of the HDRs built by Gibbs are supposed to contain his very own "psychic signature" within them, that nobody can emulate :(..

All you have to do to remove the knob from the HDR, is to find the correct screwdriver and unwind the screw that clamps onto the Pots shaft, then lift the knob off, hardly rocket science :D..
I don't buy into that. It just needs to be built without cutting corners and adding your own 'ideas'. LOL!

Did Gibbs ever say such a thing? I mean, beyond building it correctly. I certainly have never heard him say it.

Lookin' forward to knobbing off some knobs.
 

FarOutThere

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All you have to do to remove the knob from the HDR, is to find the correct screwdriver and unwind the screw that clamps onto the Pots shaft, then lift the knob off, hardly rocket science :D..
It took me 4 hours but I was eventually able to remove the knob.

j/k, although luckily I had a large range of allen keys.

10212
 

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