Help with an '83 Spoiler's Electronics

[pocket8]

Hi all,
 
This is my first time posting here, but with the experience that is out in Alembic-land, I hope that I can glean some insight into what is going on.  I just bought a 1983 Spoiler and the first thing I noticed was that the pots and Q-switch worked, but the pickup selector switch only gave signal for neck and neck-bridge positions.  The bridge position was totally dead.  I was a little miffed and felt like I bit the bait in an ebay hoax.  But since I liked the shorter scale and the Zebrawood top and laminate of the bass, I decided to keep it.  I thought, maybe just maybe, the pick ups might have different power requirements and the battery might be getting on in age (or something else might be wrong that could be remedied by switching batteries).  I did so and now the pickup selector switch does not give any signal in any position, not even with the original battery.  There do not seem to be any loose soldering points, so I am a little worried that one of the electronic components (which are 26 years old) might have gone kaput.  Since I have no skills with either electronics or a soldering iron, that would mean shipping the cadillac of the collection (the spoiler) back to Alembic and paying a pretty penny for diagnosis and possibly a new electronics package.  However, I will admit to accidentally having quickly touched the battery terminals to the reversed connector on the 9V adaptor before correcting the connection (positive to where negative should have gone and negative to where positive should have gone).  Could that accident have killed the electronics?  What is going on?  Does anyone know what it would cost (ballpark) to fix this problem, including getting a flight case with a spoiler insert for the necessary shipping?
 
Thanks much, especially if you read all the way to the end.
 
Cheers,
John

[keith_h]

First have you tried swapping the pickup connectors to see if it is in the pickup itself or the electronics?  
 
If it is determined to be in the electronics or pickups you should not have to send the complete bass in for repair. All you should have to do is remove the electronics/pickups and send those in. It is much cheaper that way. As far as cost the folks at Alembic will have to answer that.  
 
Keith

[pocket8]

Hi Keith,
 
I'm not very handy with the requisite tools, and I am a bit worried about installation and de-installation.  I'll have to go back and check all the connections to the pots and switches tonight, but everything I remember seeing underneath the control plate was soldering, not the nifty new gold plated, friction locking connections that I think they have now.  Also, I cannot get signals from either pickup when they are selected individually or together by the selection knob, so I can't really tell about the pick-ups alone.  I think that I may be able to do electronics surgery with my Fender Aerodyne, but I'm a little scared to mess with something that has more electronics in it than the T-800's neural-net processor.  
 
Even so, are you saying that it ought to be pretty straightforward to take the pickups out and send them and the electronics package to Alembic for diagnosis and repair?
 
Thanks,
John

[tbrannon]

John,
 
If the connections are soldered then they've been changed or altered somewhere along the line.  All Alembic connections use those nifty connectors...
 
If you have the ability to take a digital photo of the electronics cavity and post it here there are quite a few members who will be able to help you troubleshoot.
 
Toby

[mica]

Hi John,
 
First, even if you replaced with a brand-new fresh out of the package battery, try another one. It's a simple thing to eliminate as the possible source of the problem.  
 
There's no charge (except for the shipping) to test the electronics, but Keith's advice about swapping the pickup leads is right on. Likewise Toby's advice if the pickups are soldered on the board (or worse - soldered on the posts of the connectors).  
 
First, determine which positions of the switch are working and which pickup(s) can be heard in each position. This is best performed by starting with the most counterclockwise rotation, which should have no output since it's standby.  
 
Position 2 should have only one pickup. Confirm by tapping the pickup lightly with a screwdriver or other handy ferrous object. Position 3 should have both pickups, and position 4 should have the pickup that couldn't be heard in position 2.  
 
The pickups are identical, save the cable length to reach the cavity, so you can safely swap leads to test if the problem is in one of the pickups or is in the electronics.  
 
If you can find a local source for the 2024 IC that's socketed to the board, it's worth replacing. Just make sure you line up pin 1 on the op amp and the socket or you'll burn out the op amp. Pin 1 is denoted by a notch, a molded numeral 1 or a molded circle. Don't rely on the printing on the chip as it is not standardized.  
 
If you need to send your electronics in, please contact me by email (in my profile) before you remove the electronics for some help to make sure you can get them here safely and installed safely.

[pocket8]

Whoops... you all were right about the electronics: the pickup leads slid off the board without a hitch...my bad.  I'll test the pickups tomorrow, and if I can't get a signal with fresh batteries, I'll be in contact with Mica to solve the electronics problem.  Thanks everyone for your advice and your patience.
 
Cheers,
John