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Need CBS 410/411 Volumax Parts List

I'm rebuilding the stereo 411 for a school district's radio station and my copy of the manual doesn't have the component listings. I'm replacing all the caps due to age and I'd like to be able to get the proper values (my schematic is difficult to read being a copy of a copy) If someone has a 410/411 manual and wouldn't mind scanning the component listing pages I would be most grateful.

Thanks in advance.
 
I assume you've already found this PDF:

http://www.purpleaudio.com/pdflib/CBSVOLUMAX410411.pdf

Which is otherwise pretty clear except for, of course, the schematic

I just did a Volumax recently, as I remember it had mostly Sprague caps, with clear markings on them. I just cut them out & replaced with equivalent values from my parts supply. That unit has problems with the big output pot--I am hoping it gets retired soon.
 
Yes, that's the exact one I have.

Since I need to place a parts order by Wednesday I was hoping to get the parts listing so I didn't have to rummage through the storage room where the unit is and have to rip it apart to get the values of the components. The schematic is rough in spots to read the values and if I had the full manual (or the parts listing pages) would save me an immense amount of time.
 
I've had that one, also. Believe me, I wouldn't waste time asking for the parts listing printout if I could read these schematics with any degree of certainty (and of course there are differences in the 411 from the 400). Unfortunately I don't have the luxury of time to rip apart the unit to confirm all the values so I may just have to shelve the idea of rehabbing the unit for them.
 
As I remember from the one I did, most of the coupling caps are 20 uf at 35 volts, I just used 22/50 volt caps.
The power supply caps were either 470 uf or 1000 uf--obviously doesn't make much difference.

Just use a Sharpie to mount the + end of the leads, get a good roll of de-soldering braid (the Shack still has some the best), and have at it. Watch out for brittle wires!

You certainly can't make it any worse off than it is.
 
TomT said:
You certainly can't make it any worse off than it is.

That's for sure! I'll just order enough caps to cover both boxes of the stereo pair. I don't expect these things to sound like a modern processor, but you can't kick something that they got for free. I've got an older AM processor which I'll probably have to do the same thing for when I finally get it.
 
Bill DeFelice said:
TomT said:
You certainly can't make it any worse off than it is.

That's for sure! I'll just order enough caps to cover both boxes of the stereo pair. I don't expect these things to sound like a modern processor, but you can't kick something that they got for free. I've got an older AM processor which I'll probably have to do the same thing for when I finally get it.

Bill,
Did you got or have the part list for the Volumax 411 units??, I am in the capacitors replacement process too but all schematics are poor quality until!!!...howerver I see some like TANTALUM capacitors in the boards too and I would like to get a part list because I would like to do an Mouser order but I am in vacations and I don't have the units with me but I would to recive the parts when I return to my ofice in few weeks.

Thanks a lot anticipated,
Opacheco
 
Bill,
I have a clear user/service manual for the 411 volumax.
Give me your email again or when i get chance i will upload it.

Paul.
 
@opacheco: I got a copy of the manual but it doesn't have the parts list breakdown nor a clear copy of the schematic. I'm going to drop Paul an email and once I get a copy of his manual I can forward you the info you need unless he does so ahead of time.
 
How do these old FM Volumaxes accomodate the pre-emphasis curve? Do they just hack off the highs through a hard clipper like the Gates FM Solid Statesman does, or do they have some form of independent gain control of the high frequencies?
 
Bill DeFelice said:
TomT said:
You certainly can't make it any worse off than it is.

That's for sure! I'll just order enough caps to cover both boxes of the stereo pair. I don't expect these things to sound like a modern processor, but you can't kick something that they got for free. I've got an older AM processor which I'll probably have to do the same thing for when I finally get it.

Bill thanks for your respose by PM but I can't to response to you directily by PM because I am a very new user in this forum and exist restrictions for us(the new user).....but here my e-mail:

[email protected]

Thanks a lot for your response and help!
Opacheco.
 
Paul and Bill,
Thanks for the manual.

I checked the manual and I saw (for each unit!):

two(2) electrolitic capacitor x 200uF/50Volts
tree (3) electrolitic capacitor x 100uF/50volts
eight (8 ) electrolitic capacitors x 2uF/50Volts
one (1) electrolitic capacitor x 10uf/50Volts
one(1) tantalex x 2.2uf/20Volts
one(1) tantalex x 0.27uf/35Volts


I will proced to buy them asap in order to replace them.
Thanks agin!
Opacheco
 
I searched in Mouser an found some tatalum capacitors but I don't know what is the apropiated tantalum, the options there are:

• Tantalum Capacitors - Polymer SMD
• Tantalum Capacitors - Solid Leaded
• Tantalum Capacitors - Solid SMD
• Tantalum Capacitors - Wet

I think the second one may be the correct but I need a sugestion more.
Any comment,
Opacheco
 
I have a 410 and the manual (in a CBS vinyl covered binder, no less!) if you still need a list...

The 410/411 Volumaxes have a distinct sound when driven fairly hard that I've always liked. Wish I could find a recording Volumax. Then I'd have just about one (or more) of all the older series CBS boxes. Love 'em.
 
HadYourPhil said:
I have a 410 and the manual (in a CBS vinyl covered binder, no less!) if you still need a list...

The 410/411 Volumaxes have a distinct sound when driven fairly hard that I've always liked. Wish I could find a recording Volumax. Then I'd have just about one (or more) of all the older series CBS boxes. Love 'em.

HadYourPhil,

Acording to the both schematics(CBS 411 and the Recording CBS 420) the only difference is the two 50mH small coils L302 and L303 in te Control Board section and the 15mH small coils L300 and L301 and the Resistors R330(620Ohms), R331(620Ohms), R332(620Ohms), R333(620Ohms), R334(5.6Kohms), R335(5.6Kohms), R336(68Ohms), R337(68Ohms) between the output transformer and the Output Level T Pad in the Output Board section....

Opacheco.
 
Courtesy of Chalk Hill Educational Media's Virtual Audio Museum, there's a Recording Volumax (17th picture down the page) and it appears to have a switch to vary the high frequency gain reduction on the unit. Edit: for those who have the schematic it's on the lower right side, labeled S3.

@OKCRadioGuy: The potted module has been a secret for a long time. I've heard of people actually opening them up but I've never seen a disclosure of what components are inside them.
 
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