Forums :: Resources :: Features :: Photo Gallery :: Vintage Radio Shows :: Archives
Support This Site: Contributors :: Advertise


It is currently Apr Fri 03, 2020 2:40 am


All times are UTC [ DST ]





Post New Topic Post Reply  [ 5 posts ] 
Author Message
 Post subject: pot needed
PostPosted: Aug Tue 06, 2019 2:48 am 
Member

Joined: Jun Mon 24, 2013 3:00 pm
Posts: 1413
Location: Champaign IL 61822
I need a potentiometer for one of my HAllicrafters T-54 TVs. It is a 2.5 meg pot, linear taper.
I could use any value from 1 to 2.5 Meg. I'm currently using a 1 meg with resistors at each end.
Its the Vertical Height control. It has no DC across the element, but the element floats at about 130 volts.

The problem is the shaft. Its an ordinary late 40's - 50's style pot, the
round part 1.1 inches across, standard 3/8 inch mount. The problem is the shaft, which
has to be correct so I can use the correct matching knob.

Its the kind with a shaft that is 0.55 inches measured from the end of
the threads, is .25 inch OD, and has the little ridges along the length of the shaft and
the shaft has a big cut in it almost tyhe whole length. The picture is from Wikipedia.
Plain shafts are readily available from Digikey.

Attachment:
pot.jpg
pot.jpg [ 12.6 KiB | Viewed 758 times ]


My usual source oldradioparts.com has them, but is (hopefully temporarily) out of action.

Where do I get one?

Doug McDonald


Top
 Profile  
 
 Post subject: Re: pot needed
PostPosted: Aug Tue 06, 2019 5:34 am 
Member
User avatar

Joined: Dec Sat 24, 2011 9:17 pm
Posts: 5719
Location: Vancouver Island, Canada
Those are called Knurled Shaft, and specifically '24-spline' . Altho you may want to count your splines to compare.

You should be able to find them with the correct search words. Antique Electronic Supply has them, but I didn't search for your specs.

_________________
Watch the doughnut, not the hole.
Burl Ives, RIP, oldtimer.
[:l>)


Top
 Profile  
 
 Post subject: Re: pot needed
PostPosted: Aug Thu 08, 2019 11:40 pm 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 2096
Location: Lafayette, CO
If something from a Motorola VT71 would work, l may have some salvage. Craig


Top
 Profile  
 
 Post subject: Re: pot needed
PostPosted: Sep Wed 18, 2019 7:35 am 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 6026
Location: 253 Blanche St. Plymouth, MI USA
I specialize in controls. send me an email and I can put any shaft in most any control, or add a power switch, or whatever you want.
Mark Oppat
m oppat @comcast.net remove spaces


Top
 Profile  
 
 Post subject: Re: pot needed
PostPosted: Sep Sat 21, 2019 7:42 pm 
Member
User avatar

Joined: Jan Thu 01, 1970 1:00 am
Posts: 270
Location: wisconsin
I have 3 of the T54's and one of them I parted out and kept those 2.5M pots
its from the later model T-54 but is the same, its nice and smooth
it's Stamped 2500k which is 2.5M
I can mail it to you if you want it just pm me and I will drop it in the mail

Terry


Top
 Profile  
 
Post New Topic Post Reply  [ 5 posts ] 

All times are UTC [ DST ]


Who is online

Users browsing this forum: Lolyn and 4 guests



Search for:
Jump to:  
































-->


Privacy Policy :: Powered by phpBB