September 28, 2018 at 11:49 am #15401msmcleodParticipant
I’ve dug my dad’s old Alice 828 out of storage and have given it a good clean & test.
All seems to be fine, apart from the fader on the first channel, which doesn’t work at all. With PFL engaged, I get a decent clean signal and EQ works fine. Given that all the other faders are working, with next to no dirt/crackle, I’m tempted to rule out the fader itself as being the issue. I’ve replaced the op-amp, as it was easy to do so, but this has not made any difference.
My next step was going to remove the channel and replace the other components on channel, but before I replace everything do you have any ideas what could be the issue?
Mark.September 30, 2018 at 4:17 pm #16164Ted FletcherKeymaster
There’s no active circuitry after the fader on an 828 so it must be a connection to the fader, the fader itself, or something immediately after the fader.
My first guess is that it’s the fader…. I would offer one, but I’ve literally just run out of spares for the 828.
Another possibility is that the busrails connecting the channels have come adrift, but my best guess is that it’s the fader. You will have to check it with a multimeter.
I must advise against replacing components unless you are sure that they are faulty. The 828 has proved to be very reliable and if you are getting a good signal on PFL, then there is nothing wrong with the channel.
There are a number of places that sell 60mm faders, the problem is always the mounting of the fader knob; in manufacture we actually cut down the shaft of a standard fader to fit the knob that we used at the time.
For others reading this, I do offer a ‘service’ for 828 Mk1 and Mk 2 (The above one is most likely a Mk 2 as there’s an op amp on the board.)October 3, 2018 at 12:06 pm #16165WHoopsParticipant
If the problem is the fader like Ted suggests you should take it out and measure it.
If you get no meassurment you can still probably fi the original fader.
You have to open it up, clean it and verify the wiper is making contact with the carbon track.
Worst case scenarios in a Fader problem:
Sometimes the wiper breakes in the fader, other times the carbon tracks disintegrates, if this is the case you’re only option is to replace the fader (probably other brand)October 5, 2018 at 6:50 pm #16166msmcleodParticipant
Ted/WHoops – thanks for the heads up.
It was the fader.
The carbon track itself was fine, but the connection between the top of the track and the terminal had disintegrated.
I’ve managed to repair it using a silver conductive pen, and it’s now working as new.
Thanks again for the help!
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