a-152 Issue?

Cwejman, Livewire, TipTop Audio, Doepfer etc... Get your euro on!

Moderators: Joe., lisa, luketeaford, Kent

Post Reply
User avatar
hinterlands303
Ultra Wiggler
Posts: 835
Joined: Wed May 14, 2014 3:57 pm
Location: Detroit

a-152 Issue?

Post by hinterlands303 » Sat Dec 28, 2019 10:05 pm

Doepfer is on holiday so I thought I would try here and see if anyone had any clues about this.

My A-152 seems to be having a strange problem. The first four jacks of the switch/multiplexer section do not work at all, neither as inputs or outputs. If anything is plugged into those first 4 jacks no signal is passed. Jacks 5-8 work as both inputs and outputs BUT here's where the plot thickens. With something plugged into jack 5 (as either input or output) the signal is passed when the switch is on either 5 or 1. When something is plugged into input 6, either position 6 or position 2 outputs the signal. Same with 7/3, and 8/4. Also, if I have something plugged into jack 5, plugging something else into jack 1 makes no difference; when 1 is selected the common jack still outputs whatever is plugged in to jack 5.

What could possibly be going on? Has something been fried? Or is there a jumper in an incorrect position? The Track and Hold section works perfectly, as do the digital outs. I removed the jumpers for normaling the track and hold and multiplexer common jacks but it made no difference.

:help:

User avatar
Navs
Super Deluxe Wiggler
Posts: 4142
Joined: Fri Sep 18, 2009 3:49 am
Location: Berlin, Germany

Re: a-152 Issue?

Post by Navs » Sun Dec 29, 2019 3:54 am

If it's not dodgy jacks, is it possibly a multiplexer failure? I can't remember which chips are in the A-152, but if it uses two 4-way muxes, then it's possible that one is dead (I think there are also 8-way chips, which would make it harder to diagnose why 4 work and 4 don't).

User avatar
hinterlands303
Ultra Wiggler
Posts: 835
Joined: Wed May 14, 2014 3:57 pm
Location: Detroit

Re: a-152 Issue?

Post by hinterlands303 » Sun Dec 29, 2019 4:28 pm

Navs wrote:
Sun Dec 29, 2019 3:54 am
If it's not dodgy jacks, is it possibly a multiplexer failure? I can't remember which chips are in the A-152, but if it uses two 4-way muxes, then it's possible that one is dead (I think there are also 8-way chips, which would make it harder to diagnose why 4 work and 4 don't).
Thanks for the reply. I got it working again! One of the chips seemed slightly askew - meaning not all the way inserted - so I gave it a firm push. I also unplugged all of the ribbon cables and plugged them back in - thinking that if something was loose then that might have something to do with why the switch section wasn't working properly but the T&H and digital outs were. I'm not sure which of those two things I tried worked but one of them did something.

Post Reply

Return to “Eurorack Modules”