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Alembic Club » Owning an Alembic » Troubleshooting » Archive through June 11, 2010 » Big crackles in the neck pickup circuti - Series 1 '78 « Previous Next »

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garth4664
Junior
Username: garth4664

Post Number: 37
Registered: 10-2008
Posted on Sunday, September 13, 2009 - 1:39 am:   Edit Post

Big problem please help.

My neck pickup circuit started making loud intermittant crackling sounds at a gig last night. Fortunately could switch to the bidge and complete the gig.(When I turned down the neck pickup volume or switched the neck pickup off there was no crackling at all and the bass sounded as usual.)

I have had a chance to investigate the issue today - it is really strange. Generally speaking if i sit still and "turn" the neck pickup volume adjustment trim pot (on the back of the insrument) the crackling goes away and the neck pickup sounds clear. But if I get too vigourus or tap the back brass cover the crackling can come back (it is not the same result everytime).

I opened the back of the bass and noticed that if I tap the components on the circuit (card) I get a crackle with each tap.

Swapping the pick ups does not change the issue, I.e. the neck pickup works very fine with the bridge pickup circuit and the bridge pickup crackles through the neck pickup circuit. so the issue seems to be in the circuit (card) rather than the pickups themselves.

Mica is this something that I need to send the circuit board back to Alembic's factory to fix?

Are there any further tests I could run?

Please help,

Garth
slawie
Intermediate Member
Username: slawie

Post Number: 105
Registered: 8-2002
Posted on Monday, September 14, 2009 - 3:06 am:   Edit Post

Hey Garth sorry about the problem nothing worse that your
Alembic sounding sh!tty.

Check connectors that they are seated properly.
And also a simple thing is to run an pen eraser
(one of the rough ones - not pencil kind) on
the pins of the
connectors to lightly rough up the metal thereby cleaning the surface.

You can get one of those jewellry eye pieces
and check for dry or cracked solder joints
and or connections. I am an old fart and need one of these.
Any of you young folks can probably see it with the naked eye.
Look at the points where components or sockets
are connected to the PCB (printed circuit board)
Look for discloloured or not shiny joints or
a blackline around the component solder interface.

If you find any of these, solder it/them up,
or if you don't trust your soldering skills, find someone who can.
Or send it back to Alembic.

It might not fix the problem but it's a good place to start.
Sorry if I am repeating something you aleady have tried.

slawie
garth4664
Junior
Username: garth4664

Post Number: 38
Registered: 10-2008
Posted on Monday, September 21, 2009 - 4:10 am:   Edit Post

Thanks Slawie,

Tried all of the above - nothing out of place on the soldering side, and bass plays perfectly if I remove the PF6 and just let it dangle from the leads in the breeze with the back plate removed.

I think it is a faulty component, simply because where there is no vibration there is no noise, but perhaps it is an unobvious solder connection.

I've written to Alembic help email asking whether I should send the PF6 through to them. Hopefully it won't take them too long to repair and send back to me :-(

Life without a series 1 is going to be pretty tough. Will have to stay away from tall building windows and sharp objects.

Thanks for all the advice.

Cheers,

Garth
tdukes
Intermediate Member
Username: tdukes

Post Number: 164
Registered: 4-2008
Posted on Monday, September 21, 2009 - 5:36 am:   Edit Post

It took about a week and a day or so for me to get mine there, fixed and back again. My total cost was a little over $50. I guess the cost will depend on what's is wrong with your card and how you ship it.

My problem was a FET, sounds like you may have a bad trim pot.

Good luck,
Todd.
garth4664
Junior
Username: garth4664

Post Number: 39
Registered: 10-2008
Posted on Friday, October 02, 2009 - 6:56 pm:   Edit Post

2-3 weeks after writing the email to Alembic help still no reply. Not sure if I should just send the PF6 card back or not - will Alembic look after it if it arrives unannounced?
davehouck
Moderator
Username: davehouck

Post Number: 8816
Registered: 5-2002
Posted on Friday, October 02, 2009 - 7:02 pm:   Edit Post

Try giving Mica a call. Probably the best time would be between 10 and 4 pacific time.
mica
Moderator
Username: mica

Post Number: 6405
Registered: 6-2000
Posted on Friday, October 02, 2009 - 7:54 pm:   Edit Post

Garth, I did not see your email. You can send the card in no problem. Make sure you send it in a static-safe bag, then packed in a sturdy BOX (I will actually be mad if it arrives in a padded envelope, and you don't want to see me mad). Include a note with:

-your name and return address
-phone number/email to contact you about the repair
-serial number of your bass
-description of the problem you observed
-what troubleshooting you attempted first

There's a $75 cap on PF-6 card repairs. Shipping is additional. BTW, you should insure the card for $350, since that's the replacement value of a new one.
garth4664
Junior
Username: garth4664

Post Number: 40
Registered: 10-2008
Posted on Saturday, October 03, 2009 - 6:54 am:   Edit Post

Hello Mica,

Thanks so much - will send via hong kong express post as instructed. I will also send all the details as requested - will be so good to have the series 1 fixed...can't wait.
garth4664
Junior
Username: garth4664

Post Number: 50
Registered: 10-2008
Posted on Monday, November 23, 2009 - 8:59 pm:   Edit Post

Hello Mica, Any word on this - has the PF6 been repaired yet?

Kindest regards,

Garth
mica
Moderator
Username: mica

Post Number: 6465
Registered: 6-2000
Posted on Wednesday, November 25, 2009 - 10:26 am:   Edit Post

I am not in the office today, sorry I missed this message on Monday, but I believe it's complete and ready for return shipment. I'll check on Monday and let you know.

(Message edited by mica on November 25, 2009)
garth4664
Member
Username: garth4664

Post Number: 52
Registered: 10-2008
Posted on Tuesday, December 01, 2009 - 9:43 am:   Edit Post

Hello Mica,

Thanks - please feel free to charge my credit card (details as provided earlier) and send back to my office address. Thanks again for all your help :-), can't wait to play the old girl at my next gig.

Cheers, Garth
garth4664
Member
Username: garth4664

Post Number: 53
Registered: 10-2008
Posted on Tuesday, December 01, 2009 - 9:49 am:   Edit Post

Hello Mica,

Thanks - please feel free to charge my credit card (details as provided earlier) and send back to my office address. Thanks again for all your help :-), can't wait to play the old girl at my next gig.

Cheers, Garth
garth4664
Member
Username: garth4664

Post Number: 75
Registered: 10-2008
Posted on Thursday, December 10, 2009 - 7:00 am:   Edit Post

Hello Mica, any word on this? Has it been sent yet? would love to get the 78 coco sounding again...
garth4664
Member
Username: garth4664

Post Number: 79
Registered: 10-2008
Posted on Saturday, December 19, 2009 - 5:16 am:   Edit Post

Mica, I heard from Mary that the Alembelectrictricians couldn't figure out what is wrong with the circuit board - any news??
garth4664
Member
Username: garth4664

Post Number: 90
Registered: 10-2008
Posted on Saturday, February 06, 2010 - 6:01 pm:   Edit Post

Hello Mica,

Sent an email - is this ready to be sent back yet?

Any news?

Cheers,

Garth
garth4664
Member
Username: garth4664

Post Number: 91
Registered: 10-2008
Posted on Wednesday, February 10, 2010 - 12:26 am:   Edit Post

Any news would be good news? Help?
garth4664
Intermediate Member
Username: garth4664

Post Number: 101
Registered: 10-2008
Posted on Wednesday, February 24, 2010 - 4:01 am:   Edit Post

Mica - is anyone there - have sent emails...
garth4664
Intermediate Member
Username: garth4664

Post Number: 113
Registered: 10-2008
Posted on Wednesday, March 17, 2010 - 12:05 pm:   Edit Post

Still no word on this repair - can someone call Alembic for me or mention it when they chat, I would really like to get my Cocobolo sounding again.

Cheers Garth
mica
Moderator
Username: mica

Post Number: 6659
Registered: 6-2000
Posted on Wednesday, March 17, 2010 - 6:37 pm:   Edit Post

Hmm, this was set aside after inconclusive tests and sadly overlooked. Dad is doing some more tests on it (at this moment!) and I hope to have some more details for you in a day or two.

Sorry this is taking so long.
garth4664
Intermediate Member
Username: garth4664

Post Number: 114
Registered: 10-2008
Posted on Thursday, March 18, 2010 - 4:54 pm:   Edit Post

Thanks Mica, I can see from the site how busy things are there. Just glad to hear that you are on the case. Look forward to hearing the results of the test.
mica
Moderator
Username: mica

Post Number: 6660
Registered: 6-2000
Posted on Thursday, March 18, 2010 - 5:42 pm:   Edit Post

Found some problems - which is good. But they were a little trixy! Looks totally fixed, just one more string of tests and we'll ship it off. Email me your current shipping address, it's been so long, you may have moved in the meantime.
garth4664
Intermediate Member
Username: garth4664

Post Number: 115
Registered: 10-2008
Posted on Wednesday, March 24, 2010 - 2:57 am:   Edit Post

Hello Mica,

Actually I have moved countries since then but will get you to send back to my wife's work address in Hong Kong. I will send you the current shipping address in Hong Kong via email.

Thanks again and look forward to getting the coco sounding again.

Cheers, Garth
garth4664
Intermediate Member
Username: garth4664

Post Number: 118
Registered: 10-2008
Posted on Sunday, April 11, 2010 - 4:23 am:   Edit Post

Hello mica, did you get my email? Is my PF6 being sent back? Thanks
garth4664
Intermediate Member
Username: garth4664

Post Number: 119
Registered: 10-2008
Posted on Thursday, May 13, 2010 - 6:44 am:   Edit Post

Still nothing from you Mica, Susan. Can you please email me at garth4664@gmail.com

Has been a long time for this PF6 card.
mica
Moderator
Username: mica

Post Number: 6744
Registered: 6-2000
Posted on Thursday, May 13, 2010 - 6:29 pm:   Edit Post

How lame is that? The parcel was all perfectly packed, customs form all filled out, and then safely covered by some packing material until today.

It's outta here in the am post - I will confirm that the same has happened for you tomorrow. Sorry for the delay.
garth4664
Intermediate Member
Username: garth4664

Post Number: 120
Registered: 10-2008
Posted on Saturday, May 15, 2010 - 12:54 am:   Edit Post

Thanks Mica, really can't wait to put this bass back in service. I miss it badly.
garth4664
Intermediate Member
Username: garth4664

Post Number: 123
Registered: 10-2008
Posted on Thursday, June 03, 2010 - 10:18 pm:   Edit Post

Hello Mica,

PF-6 back in place and bass sounding great. Thanks for your help, I'm so glad to have this one back in service, it is a great sounding bass with such a clear tone. I think I like the sound slightly more than it's better looking sister, 76AC070. This is the first time I have had the chance to compare them back to back. :-)

I'm so happy, thanks again.
jacko
Senior Member
Username: jacko

Post Number: 2618
Registered: 10-2002
Posted on Friday, June 04, 2010 - 4:24 am:   Edit Post

I just love a happy ending ;-)

Graeme

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