Author Topic: Series I pickups trouble - help ! (Read 105 times)

artbass · « **on:** January 01, 2006, 03:50:39 PM »

Hello from Italy and happy new year at all.

I purchased a 1978 Series I abused and I'm restoring It.
I measured both pickups resistance and I found that the neck pickup was about 2M ohms and the bridge pickup was about 2.8K ohms.
As described above, the neck pickup resistence is very very high but it seems to work perfectly.
I tested both pickups output and it is the same, also the frequency response seems good.
I'm worried about this problem and I want to clarify it.
Please let me know if the pickups are OK or if I have to change they.

I'm sure that you can help me.
Thanks for your time,
Arturo

mica · « **Reply #1 on:** January 01, 2006, 03:57:27 PM »

Hi Arturo,

The measurement from the neck pickups indicates that it should be dead. There are instances that is would still work, but it probably won't be effective when you try the humcancelling procedure. Have you attempted it yet?

Please post your results when you have them. You may need to replace the pickup(s), unless you are satisfied with the present function, then just enjoy the bass.

artbass · « **Reply #2 on:** January 01, 2006, 05:22:01 PM »

Hello Mica, thanks for your fast reply.
I know electronics and this matter is very strange.
The humcancelling procedure works fine. It is effective in both pickups with the same results.

I retested the resistance, 2M ohm in the neck pickup.
I have never seen anything similar !
The Alembic is magic, It's sick and It wants survive. This is a miracle.

Mica, I suspect an oxidation problem inside the pickup in the output wire contacts points.
If you can, I pray you to tell me the 1978 pickup construction and assembly procedures so I can see were could be the problem ( you can send me simply a draft ). I have the chance to open the pickup with capillary work with a dremel tool, it will be a surgical operation. This is only to preserve the original pickup.

If I will decide to replace the pickup I have some question for you.
Can I order only one pickup ?
As you know, my pickups don't have the alembic logo in the cover.
Is there a reissue model ?
Otherwise what's the best solution for my 1978 Series I ?

Thanks again for your care,
Arturo

artbass · « **Reply #3 on:** January 08, 2006, 12:24:28 PM »

Hi Mica, I hope that you have read my previous post.
I decided to replace the neck pickup.
Let me know if I have to change only the neck pickup or both.
Also please let me know the prices.
Thanks again

mica · « **Reply #4 on:** January 09, 2006, 04:15:45 PM »

You can order just one pickup, but a set of pickups that are matched will perform better. When you order, please have the serial number of your bass and also specify that you want the plain pickup (without gold stamping or engraving).

The pickups are single coil, which has an expanded copper shielding cage around it. This is suspended by wires in a silicone mold. We then pour polyurethane compound to make the shape of the pickup. Everything is molded together, so chances of a repair are very slim.