Braun CSV-1000 restoration

[paul_ral]

Hi gents!
My name is Paul, I am living in Romania and I repair or do restorations of vintage audio. A few months ago I bought a defective Braun CE-1000 tuner, with no transformer but I manage to make one graceful Petra Toroid from Iasi. I changed all electrolytics capacitors, few lamps and the tuner works great!





A few days ago I found its amplifier Braun CSV-1000 which is also defective. No transformer inside, the phono board is missing too, no power resistors in power source and more important, no relays board which it is used to switch the inputs. The wires between input sources and the relays board are cut but I can manage to restore them.
These old pieces looks great





My goal is to make this amplifier working again. It is a huge effort I will change all electrolityc capacitors with radials or axials according the board layout, new toroidal transformer and I search for the relays board which seems to be very difficult to find.

[paul_ral]

I started to restore the amplifier dismantling all boards I have.
Main amp board. Some transistors have been replaced, I will test all of them

Power supply dual boards

Preamplifier board

The output transistors and capacitors

The PS capacitors

[paul_ral]

As I said before my CSV comes without transformer, I don t know what has happened with this unit. My serial number is 10886 and I will follow the proper scematic diagram in order to restore the power supply.


I ordered a new toroidal transformer using the voltages found in another CSV-1000 topic and the dimensions from inside. Checking the clearance, it looks good!






The power supply was damaged as I can see, some parts are missing: the power resistors in series behind the transformer, rectifier diodes and original trimmer





I replaced all electrolitycs using Vishay axial ones, new resistors and zener diodes. The original transistor BFY41 was replaced with BF258. I choose to use a powerful 2N3440 for this application.The original trimmer 1.2kohms at 3 W was replaced by a standard 0.5W one and was damaged. I will replace with a 4W potentiometer.




To be continued.

[paul_ral]

Main amp board recapped
Before

After

[paul_ral]

C802 (800uF) and C805 (2500uF) are screw ones, they are expensive on Mouser and I found a cheap approach using snap-in capacitors with clamp. I bought Nippon-Chemicon for C802 (820uF) and 3300uF for C805 I have on hand.

In the cage





I will replace the missing rectifier bridge with a proper one and I have to find a way to put the power resistors behind the transformer.

[henry2]

Hi Paul,

You have done a very good job so far, taking into account the fact that it is certainly not easy to get original parts from Braun devices in Romania.

I noticed a few things: Please make sure that the correct load values of the resistors on the small control circuit board for the stabilized power supply match the information in the circuit diagram. The same applies to replacing the two Zener diodes ZD56 and ZD75. They must have at least 1.3W.

There seems to be little space behind the new mains transformer. As a replacement for the six 43Ω/9W resistors, 2 high-load 15Ω/50W resistors connected in parallel could also work. See also the link: https://www.reichelt.de/drahtwiderstand ... ol_3&nbc=1 as an illustrative example.

Replacing the many small electrolytic capacitors (>50 pieces) on the preamplifier board is also a lot of diligence and requires some patience, but you certainly seem to have it.

Unfortunately I can't get you a relay board, but if you want, I can perhaps organize a small phono amplifier module for you.

I wish you every success in your fine task of bringing the CSV1000 back to life.

Best regards

Heinrich

[paul_ral]

Thank you for your reply Heinrich! You are right, no many Braun in Romania, Braun is not ver popular in my country, so it is very difficult to source parts. But this is not only in RO, it seems to be all over the globe. As I told before I bought and restore CE-1000 tuner without mains transformer. I bought one from e..y, it was from a little radio but it fit inside. I want to rewire it but Petra Toroid from Iasi do not agree and they made a new toroidal transformer which works great. That transformer was arround 40euro.

Regarding the resistors from PS I follow the schematic diagram for upper 10500, except R810 1.5k at 0.5W, all are 0.25W. Both zeners are 1.3W and transistor T804 is 2N3440 now. As for parallel resistors load I bought them but I will follow you suggestion. I could manage the space inside better. Thank you.

No issue in changing capacitors, Saba 9260 is the champion!

I will be very glad to see some pictures with relays board. From my research and watching all pictures from inside, I notice they use Haller 3532relay type. Haller is Hengstler now, they told my there was no replacement for original relay. I can try doing a replica board using new relays type, my secondary transformer coil is for 12V.

Best regards,
Paul

[paul_ral]

Another board is ready. I use Nichicon Fine Gold and KL (low leakage) and axials from Vishay

[henry2]

Hallo Paul,

wirklich saubere Arbeit bis jetzt! Ich hoffe für Dich, dass Du noch von irgendwoher eine Relaisplatine organisieren kannst.

Viel Glück und viele Grüße

Heinrich

[paul_ral]

I search every day for that board. I also found a half of CSV-1000/1 with transformer, power supply boards, rectifier diodes, power amp, heatsinks, a complete amp section I could say. I try to keep it original so I will replace the missing parts with OEM ones. I can also make a final amplifier with remaining parts I have.

I am thinking about makeing a replica board using low signal relays like RY-12WFZ-K from FCL Components. I can put 2 relays in parallel in order to replace the original Haller relays.

[paul_ral]

A half of CSV-1000 from Germany

[paul_ral]

Back to my CSV-1000. As I understood the voltage for primary coil came through blue cable with 3 wires: black, white and red. Red will be the ground, connected through 4700pF capacitor to negative pole of C802.



The trimmer goes to my CSV



I remove the main transformer. The wires have been cut, there are 2 black and 4 brown according to their insulatings. I have to identify their position and connect them to input voltage switch




The puzzle needs to be solved!

[henry2]

Hi Paul,

you're doing a great job so far, and that with great expertise. I'm particularly pleased that you're trying to maintain originality wherever possible.

Best regards

Heinrich

[paul_ral]

Ready for the first start again!


It is a mistake here (connecting point encircled in blue)?

[henry2]

Hi Paul,

no, it is not a mistake here (connecting point encircled in blue). It is the minus-reference point of the 10V DC for the relais-board and the control lamps.

Greetings Heinrich

[paul_ral]

Thank you Heinrich. I ask that because the schematic for early model does not have that connection point.

[paul_ral]

Checking the voltages

[paul_ral]

Checking the output transistors in original CSV: one pair is OEM RCA, one pair is different. In my test one 2N30055 looks to be germanium type.


It is nice to have spare parts. Il use the outputs from CSV1000/1, all are RCA and are good ones.




In CSV1000/1 I have 3000uf capacitors. These will be replaced by 4700uF/63V from F&T

[paul_ral]

New capacitors inside. After that I can close the main amp section. Tested on dim bulb tester it looks to be ok, no smoke, I have to test it with signal generator

[sadomskyj]

Hello Paul,

Your work looks very good. My current work on a CSV 1000/1 is harmless in comparison.
I would replace the marked capacitor on the power supply, perhaps you were planning to do that anyway.

Regards
Michael

[paul_ral]

Hello Michael,

I have a new capacitor for that one I will replace it soon. My goals was to finish with main amp section and to find the missing relay board, maybe I can find one in Germany.

Best regards
Paul

[paul_ral]

A little break in order to resurect two ASC. AS-2000 and AS-3001 are working great again

[wh_röhr]

Hello Paul!

Congratulation - two AS-CR - that´s not "mainstream".

Well - in my livingroom still working two AS-CR (AS3000/AS2000)
since more than 30 years without trouble...

Greetings
Wolfgang




<<<offtopic ends

[paul_ral]

Thank you Wolfgang!

These decks are not mine, belongs to a friend of mine from Germany. They made a long trip to Romania and back but I could save them. With the new capacitors inside, revised drive and new belts I belive they will work many years from now.

Best regards
Paul