337alant
Negatively Biased
Thinking about having a go at repairing one of my old Scanspeak D2905-9500 tweeters with an open circuit voice coil, so nothing to loose.
I bought a pair of 28mm voice coils off ebay for £29.99
http://rover.ebay.com/rover/1/710-5...0001&campid=5338728743&icep_item=143905478289
I have stripped down the tweeter and compared the 2 voice coils the e-bay coil fits in the groove ok but when you look at the coil windings the original has twice as many winding and is mounted on a metal ring
the ebay coil is mounted on a plastic or celluloid tube ?.
Q. Am I wasting my time?
If not I do have some more questions as I haven't done this before:-
Q1 - what type of glue should I use for reinstallation of the washers and gluing the cap back on to the spacer washer.
Q2 - there is ferro fluid in the groove, should I clean that out and replace it ?, if so where to get the right type of ferro fluid from.
Q3 - there is no polarity marked on the new coils lead wires but one wire goes to the bottom of the coil and one goes to the top, how do I confirm the polarity ?
See pics below
IMG_3683 by Alan Towell, on Flickr
IMG_3689 (2) by Alan Towell, on Flickr
IMG_3689 (3) by Alan Towell, on Flickr
Alan
I bought a pair of 28mm voice coils off ebay for £29.99
http://rover.ebay.com/rover/1/710-5...0001&campid=5338728743&icep_item=143905478289
I have stripped down the tweeter and compared the 2 voice coils the e-bay coil fits in the groove ok but when you look at the coil windings the original has twice as many winding and is mounted on a metal ring
the ebay coil is mounted on a plastic or celluloid tube ?.
Q. Am I wasting my time?
If not I do have some more questions as I haven't done this before:-
Q1 - what type of glue should I use for reinstallation of the washers and gluing the cap back on to the spacer washer.
Q2 - there is ferro fluid in the groove, should I clean that out and replace it ?, if so where to get the right type of ferro fluid from.
Q3 - there is no polarity marked on the new coils lead wires but one wire goes to the bottom of the coil and one goes to the top, how do I confirm the polarity ?
See pics below
IMG_3683 by Alan Towell, on Flickr
IMG_3689 (2) by Alan Towell, on Flickr
IMG_3689 (3) by Alan Towell, on Flickr
Alan
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