HISTORY:
In our previous audio post production business we experimented with many different loudspeaker systems and their components. This is now a LONG time ago and while sorting through my box of spare parts I came across this mystery crossover. I have no idea which manufacturer's system this came from or even the loudspeaker configuration but I have suspicions this was part of a PA horn feed crossover - not 100% on that but it is my "gut feeling"
UNBRANDED - Crossover Network (1)
Model: unknown
Very old substrate base with point to point wiring underneath (this is not a PCB or PWB) - I am unsure about the substrate material but it is NOT modern! It may be bakelite or a compound of materials, certainly there is no plastics or fibreglass at all. I vaguely remember seeing this type of substrate from equipment back in the 1950's!
Two connections (short leads) on one side of the board and the same on the other side
Two very impressive inductors (air core) which are 33mm diameter each with heavy gauge wire, only 10 turns in total! I tried measuring the inductance, the value was too low and my little L tester couldn't tell me the value.
Four 5W wirewound resistors, each is 10R value
Two polypropylene film caps, each is 0.1uF 630V made by Arcotronics (now acquired by KEMET) and I still see these caps being sold online. It seems that Arcotronics were formed in 1954 and part of the Plessey group originally.
Other markings on these capacitors are:
R73 KP
JO
I did test these capacitors and the values are practically spot on.
Thats it! Nothing more on the board.
Now packed away in clear plastic and hopefully someone will see potential as a "component farm" or other use
