View Single Post
Old 19th Oct 2020, 9:08 am   #27
barrymagrec
Octode
 
Join Date: Dec 2017
Location: Morden, Surrey, UK.
Posts: 1,557
Default Re: Sound Belle reel-to-reel heads

Quote:
Originally Posted by jmcilkley View Post
Sorry, Barry. I did see your post but I didn't understand the 2 coils bit. I was wondering if the 2nd coil was useable as the one being used is clearly defective. Without the wires connected to the head I can see the correct signals on my scope showing the bias at about 48k and sound from the microphone superimposed. With the wires connected to the head - nothing. So I'm sure the head is faulty.
The two windings are wound round the two pole pieces so both are required to make a complete head. have you checked the continuity of each half?

The drive to a record head is normally more or less constant current so you would expect a big drop in level when you actually connect the head to the amplifier / bias signal though you should still see something unless the head is dead short, which would be unusual.
barrymagrec is online now