Page 2 of 2
Re: Fender Blackface Vibroverb
Posted: Mon Jun 12, 2017 7:34 am
by Roe
Yeah, that's the aa763 - those are rare and valuable
Re: Fender Blackface Vibroverb
Posted: Mon Jun 12, 2017 11:45 am
by Freebird
Roe wrote:Yeah, that's the aa763 - those are rare and valuable
Thanks Roe
Good to know they are rare and valuable. The amp holder told me he has to be very careful if he is doing gigs with this amp. Someone has always to keep an eye on it.
Daniel
Re: Fender Blackface Vibroverb
Posted: Fri Jun 16, 2017 8:16 am
by Freebird
Hi forum members
Do I have to swap the brown
Astron tone caps on the main circuit board:
https://www.dropbox.com/sh/fy1uup7kduem ... G_3797.jpg? Can they get bad over time? The blue molded I think rarely need replacement, isn't it so?
Any related input is welcome! Thanks,
Daniel
Re: Fender Blackface Vibroverb
Posted: Fri Jun 16, 2017 9:13 pm
by danman
Are you referring to the big, round electrolytic caps on the board? If so, then yes...it's a good idea to swap those also as they are way past their useful life. I also saw a brown drop on your board I believe. They are film caps and they do not suffer the effects of time like electrolytics do.
Re: Fender Blackface Vibroverb
Posted: Sun Jun 18, 2017 7:54 am
by Freebird
danman wrote:Are you referring to the big, round electrolytic caps on the board? If so, then yes...it's a good idea to swap those also as they are way past their useful life. I also saw a brown drop on your board I believe. They are film caps and they do not suffer the effects of time like electrolytics do.
Hi danman
Thank you for your response. Yes, referring to the big oily paper caps on the cathode: three of them have 2x25uF/25VDC
and one has 25uF/25VDC . I then will swap them too.
The smaller browny ones seems for me also that they are film caps. I let them as they are in.
Daniel
Re: Fender Blackface Vibroverb
Posted: Mon Jun 19, 2017 7:36 pm
by danman
Yes...the 25uf/25v are well past their useful life. If the amp is a player, I would want to replace them with fresh caps.
Re: Fender Blackface Vibroverb
Posted: Sat Jun 24, 2017 5:19 am
by Freebird
danman wrote:Yes...the 25uf/25v are well past their useful life. If the amp is a player, I would want to replace them with fresh caps.
Thanks danman for your confirmation. The amp is a player and has to be it for further 25 or 50 years
.
Daniel
Re: Fender Blackface Vibroverb
Posted: Sat Jun 24, 2017 5:37 am
by Freebird
Today I swapped the Astron tone caps (2x25uF/25 VDC) on the main board with new TAD's (2x25uF/25 VDC). After I soldered out the old brown Astron caps I measured them against TAD: Here the approximate values:
Astron: 45-70 uF and ESR 1.9-6.5 Ohm at 1 kHz (a very bad one has 8.5 nF nano! and ESR 28 kOhm kilo!)
TAD: 24-24.5 uF and ESR 0.11-0.12 Ohm at 1 kHz
It confirms, that the old Astron Caps has to be replaced with new ones. Enclosed a picture:
https://www.dropbox.com/s/vvkjnvw1b8woy ... 8.JPG?dl=0
Daniel
Re: Fender Blackface Vibroverb
Posted: Sat Jun 24, 2017 8:47 pm
by danman
The amp should sound great when your done!!
Re: Fender Blackface Vibroverb
Posted: Mon Jun 26, 2017 3:39 pm
by Freebird
danman wrote:The amp should sound great when your done!!
Yes danman, it really sounds much better and the amp is more stable. Also there is less hum.
New filter caps:
https://www.dropbox.com/s/t4eb1b1ypyv45 ... 2.JPG?dl=0
New tone caps:
https://www.dropbox.com/s/x72xrnp5ejeru ... 9.JPG?dl=0
New bias cap:
https://www.dropbox.com/s/3m4g1zt694t73 ... 7.jpg?dl=0
Additional grid stoppers:
https://www.dropbox.com/s/qtu1aui87dg8j ... 8.jpg?dl=0
I hope my guitar friend is satisfied and happy with my job.
Only if I watch the small new bias cap I am a little bit scared. I hope it is a good one?!
Daniel
Re: Fender Blackface Vibroverb
Posted: Mon Jun 26, 2017 5:10 pm
by neikeel
Thanks for sharing that.
Still hanker for a nice clean BF Fender, waiting for BFDR to fall into my lap in the same condition as that one!
Re: Fender Blackface Vibroverb
Posted: Tue Jun 27, 2017 12:32 pm
by Freebird
neikeel wrote:Thanks for sharing that.
Still hanker for a nice clean BF Fender, waiting for BFDR to fall into my lap in the same condition as that one!
My pleasure! It was fun to restore such an old amp. Thanks to all of you who helped me to come through!
Don't know how many Blackface Vibroverb AA763 from 1963-64 are made by Fender? Anyway, I wish you good work on your Blackface Fender!
Daniel