Harman Kardon Recaps, 430, Citation 11 & 16

[ficklecycler]

I'd love to see some pictures of the rebuild of your Citation Eleven if you have them.

 

[Sir.Byrd]

When I remove it from the system I'll take some pictures.

 

[bobrown14]

I'd love to see some pictures of the rebuild of your Citation Eleven if you have them.

+1 - pics would be great!

Cheers,
Bob

 

[AmCan]

Nevermind about the RCA jacks, I figured it out and then I broke the original plate.
No worries, I made a new one out of bubinga.

Hey Sir Bird,

I would like to remove some riveted RCA jacks in order to reuse the same board on my amp and remembered this from your thread that you knew how to remove them. Can you please tell me what you figured out about getting these things out?

Thanks

 

[Sir.Byrd]

The RCA jacks were coming out when you grabbed some adjustable vice grips and crush the barrel, but it is tricky in order to not break the plate.
You may find a better way to do it.

 

[AmCan]

I figured it was something like that. I'll end up giving it a try. What other choice do I have. If it breaks then I will make a new plate.

Cheers, :thmbsp:

 

[Sir.Byrd]

I got six of them out before it broke. Luckily I could still use the broken plate as a template.

 

[Zolton]

new to me 430

I just picked up a 430 myself. I've got quite a number of components sitting on a shelf that need repair / recap but I've not attempted one yet. I just seem to be collecting stuff at this point. I'm sure no one else here has experienced this phenomenon
So this will be my first. I'm happy to hear that he 430 is easy to work on. It'll be a good one to cut my teeth on.
The unit is very dirty on the inside. The intial DC offset readings are; -20mV Right, 32mV left. After a quick scan of the service manual., it doesn't looks as though the offset is adjustable. Only the DC idling voltage (probably have that term wrong), which is to be 25mV across R427 and R428 (with an 8 ohm resistor across the speaker terminals).
I'll be picking brains here so I hope this thread gets some new life breathed into it.
Here are the obligatory nudies.

 

[Sir.Byrd]

DC idling voltage is just a way of saying Bias.

You're right with the DC offset not being adjustable, but you can lower it with closer matched transistors, I'm not sure which they are though.
Your readings are fine, and they might get better with a recap.

 

[Zolton]

I knew I had the wrong term
I've adjusted the DC offset in everything I own so far. Just because I'm a perfectionist. The standard I go by is as follows (I got this here at some point);

0 - 15 mV = excellent
16 - 30 mv = good
31 - 50 mV = acceptable
51 -85 mV = something requires attention
>100 mV = unit will sound like shite
600mV or so will activate the protection relay if so equipped.

Sound reasonable?

Also...does it make a difference if the DC value is a negative one, especially if one channel is negative and one positive? In otherwords, do the two channel's values relate to one another. For example in the case of this 430, the difference between the two would be about 52 mV total.

 

[Sir.Byrd]

No difference if it is positive or negative.
Shouldn't matter if the two channels are different.

 

[AmCan]

I just picked up a 430 myself. I've got quite a number of components sitting on a shelf that need repair / recap but I've not attempted one yet. I just seem to be collecting stuff at this point. I'm sure no one else here has experienced this phenomenon
So this will be my first. I'm happy to hear that he 430 is easy to work on. It'll be a good one to cut my teeth on.
The unit is very dirty on the inside. The intial DC offset readings are; -20mV Right, 32mV left. After a quick scan of the service manual., it doesn't looks as though the offset is adjustable. Only the DC idling voltage (probably have that term wrong), which is to be 25mV across R427 and R428 (with an 8 ohm resistor across the speaker terminals).
I'll be picking brains here so I hope this thread gets some new life breathed into it.
Here are the obligatory nudies.

Just to clarify, where did you take these readings?

-20mV Right, 32mV left.

Did you take them

across R427 and R428

If you did then these are your bias measurements. Bias can be changed by turning a variable resistor pot usually on the Driver Board. If you are measuring DC at the speaker terminals then that's different.

 

[Zolton]

Took them at the speaker terminals.:thmbsp:

 

[wizang]

I know this is major thread necro, but I would love love love a cap list if you have that handy, planning on undertaking this myself soon. Especially for the filter caps (c6-9 i believe), I'm really unsure what to get to match the 4 pin style.

 

[Sir.Byrd]

Not sure if I have a digital copy, but I could check to see if I saved it.
I found drop in replacement caps for the 4-pin style.

 

[rotini]

I'd be interested in such a list as well. I just finished recapping my Pioneer SX 950 today (save for the Phono board) and am very impressed with how the sound cleaned up.

The BC550's seem to have been replaced by 863-BC550CG's - still good?

If you can't find it, I plan on doing a recap (possibly after my Philips 7871) and will be putting together a list/BOM that I can post here.

 

[wizang]

Hey Sir Byrd, you mentioned in another thread that you used 10kuF panasonic 4 post caps for your recap? I'm having trouble finding anything under 15k. Also, what effect does it have to increase the capacitance on the filter caps so much? These also seem to be quite expensive. Are there alternatives that might function similarly? Thanks a bunch.

Also, Rotini if you ever did a BOM for this project, I'd love to see it.

 

[Sir.Byrd]

Are you shopping on mouser?

 

[Sir.Byrd]

I think this is what I used:
http://www.mouser.com/ProductDetail...GAEpiMZZMtZ1n0r9vR22aXvC6H9xGjIQY%2bNAcXQSxM=

 

[Sir.Byrd]

Wait, those are wrong. These should work fine.
http://www.mouser.com/ProductDetail...=sGAEpiMZZMtZ1n0r9vR22RSFeKT/CuZ6OfXzFsaR1no=