HISTORY:
Like nice shiny "Gold like" components? I used to keep just about any component that looked "different" and this pot fits the bill.
It isn't the value or taper that is special, but the construction is to a very high standard and it's a great museum example of IRC product from Australia, around the 1970's or so - I saw this series in one of their catalogues dating back that far.
IRC (AUSTRALIA) - Rotary Potentiometer
Country of origin: Australia
Part # F9 25000 Ω /C 32/54
25K Ohm
C Taper (Reverse Log)
300 degree rotation
Non-sealed
Solid Brass round shaft with topside slot
Solder terminals
PHYSICAL CHARACTERISTICS:
Body Only: 23mm OD x 11.75mm height
9.3mm diameter thread, suits use with a 9.5 ~ 10mm panel hole
6.35mm diameter shaft
Shaft, nut thread, nut are all solid Brass (Oh you shiny thing you!)
The solder tags look to be Nickel plated
All identification is stamped around the side of the pot body AND in addition to this, neatly hidden (slightly) is the IRC logo stamped onto the topside of the body.
This stamp on the top clearly identifies the source as IRC AUSTRALIA
The Brass shaft is LONG at 39mm length and of this length, the slot is 15mm length. This means that if the slot is of no use, just cut away this section of the shaft, leaving a length of 24mm to work with.
I hear you ... that's all very well but does it work?
Although "grandaddy's" of the pot world, these were looked after and kept in sealed packets waiting for that special day when they could be put to use - for me, that day never came!
DC track resistance measured at 27K Ohm
Lowest possible resistance wiper to either end of the track is 20 Ohm
Moving the wiper slowly across the entire length of the track, the resistance from wiper to one side very slowly increases from 20 Ohm until around the midway of rotation and it still measures just 3K Ohm. Continuing the rotation, the resistance dramatically increases as it is rotated until it reaches 27K Ohm. This is definitely a reverse log pot and the coding on the stamped part number (/C) confirms this.
COSMETIC CONDITION:
NEW Old Stock
Oh you shiny thing! Yes, I couldn't help myself and gave it a good "rub up"
NO damage physically at all
Now that I have finished examining this pot it has been resealed into a clear plastic packet, waiting for a new workshop to live in
