9941 mit Relais?

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Good morning to all......i have a problem to download the ULTRA HIFI SABA 9940 / 9941 pdf service manual, exactaly as Alf Neumann in a post before: does someone help to me where i am in error? I have just the same help to a member of this forum by a private message and i think it was not quite correct....can anyone answer me? I I JUST bought this Saba 9941 Ultra Hifi compact on Ebay and it has several problems to recieve FM stereo radio programs, also problems with the logic functions on the tape deck and problems on the dc power supply. Maybe then i will explain the details! so, first, I make a good reading of the service manual and only after asking questions to seek help. Good day to all forum members! Giuseppe Mazzilli, Roma.

Hello Giuseppe,
To use the download area, You have to create a new account there.

To 8100: Ah, of course!! how I did not understand this? very well, I was able to download the complete file. Now i will spend some time to fully understand the schematic diagram (it is well done!), Then i will ask for your useful help and advise, if possible. The Saba 9941 is a device really well done, I still have not heard the sound ( problems to power supply), but looking at the wiring diagram of the Bf line from the beginning to the final stage I expect a good sound. The tape deck diagram is particular..... the strength of the device is the tuner, i think. Two transistor Fets on the front end !! The diagram also shows the alignment operations, fantastic! I've been viewing the forum, very nice to share the same passions! 8100, thanks again and see you soon.

Hello Giuseppe,

as i own a 9940 (nearly identical to 9941) i have experienced some problems in the meantime. In my set the power supply was the part to be overworked most. The big capacitors were leaking and most voltages were out of range (to diagram).
Perhaps you start with the power supply, maybe some additional problems solve themselves after that.

To Tapeworm664 : very well said, I will leave with certainly repair the power supply and so the rest of the circuit. Yesvery well said, Yes, the noise smoothing capacitors have lost acid, but luckily no damages to printed circuit. I will work quietly, in the meantime I taste to read the wiring diagram on the train I take every day to go to work! we remain tuned, see you soon and thanks again!

Hello guys, today is Saturday and we start from here. We begin to repair the power .... We have, in short-circuit, the two capacitors marked with the resistance of 2.2 ohm / 2w. There are two blown fuses 2AT also, plugged into the same circuit. Fortunately, as you can see, there is no reversal of acid. The photo resolution is limited by the load capacity of the server, it is good the same! Thank you all and see you later! Giuseppe Mazzilli from Rome, Italy.

Hello Giuseppe,

After Si 1411 and 1412 are blown, i would suggest to check / do the following:

- Check / replace rectifier D 1427 with a DIL 80 volt / 1 Amp type, the originally built in type is often faulty.
- Check the resistor 2.2 ohms. This should be a saftey resistor, a combination of a fuse and resistor. Replace best with a 2.2 ohms 0.6 watts metal-film resistor in line with a fuse of about 0.63 amp rating (slow).
- in any case replace the red Röderstein capacitor C1428 with a good 220 µF / 63 (better 100) Volt type.
- last check T 1433 / 1434 for shorts.

Next the other power-line:

- replace the green "Herrmann" rectifier with a apropriate type. The "Herrmann"s often cause trouble. I think it will have a short on at least one diode.
- check / better replace the 4,700 and 2,200 µF capacitors with good new ones. If the rectifier was defective, the suffer under the conditions.

After that is done, replace the fuses and start the power supply board.
Please let us know about the measurements of the voltages...

Hello Gunnar, thank for your reply. I hope that other lovers of the product give me a help as you ! Initially I thought I confine myself to the replacement of defective parts only, to avoid intervening too invasive. In light of what you said to me, thanks to the experience you have on the product, I will do as you advise me. I am sorry, however, to change those beautiful capacitors Elko (2200MF / 6800 MF) which have not given acid and look good with the test instrument capacitance. The capacitors 4700MF/16V instead are in short - circuit because the voltage at which they work is too close to the maximum value that the capacitors tolerate. Generally gets so because if the Operating voltage is close to the maximum voltage value of the capacitor, the capacitor works better. The capacitor of which I speak must be an AC filter capacitor mounted on a line ripple. (Another question is for the capacitor voltage on a line audio BF). From the calculations I've done, I noted, however, that the capacity 6800MF is undersized compared to necessary. THE SABA UHC 9940 has a lower Rms power output but has a greater filtering: 10.000MF + 10.000MF (but divided by 2 channel that is always 10.000MF each channel) which means about 4,5 A max. And indeed: 45w Rms (Saba 9940) :

V * V
P = -------------
R

V * V
45 w = -------
4 ohms



180 = V * V

So:

V = 13,41 Ac Rms volts, at maximum volume.



But P is also :

P = V* I

For which:

45 = 13,41 * I


I = 3,5 A

So the capacitor 10.000MF ( = 4,5 A. ) is mounted correctly and it offers a good upper margin of safety, as it should be !


Now, with the same procedure, analyzing the Saba UHC 9941 we know it has 70w/ch. The Saba 9941 instead has a 6800MF filter, that provides 3 Amps max. The power is 70w/ch Rms, which means a need for about 4.5 Amps = about 11,000 MF. This means that the current produced by the filter capacitor in the period in which the bridge rectifier is not conducting, is JUST suffcient. So what has prompted the German designers Saba to do so? I think simply the problem of space. A capacitor Elko 10.000MF / 40v ( 63v ) would be taller and big to be fitted well without touching, at the top, the plastic support of the Radio tuner. So, I would try replacing the capacitor 6800MF with 15.000MF, if possible. First I have to try it and check if there are any mechanical compatibility of the assembly. Dear Gunnar, what do you think of this? Thanks for the valuable advice you gave me and see you soon !!! Giuseppe.

The Beautifull 6800MF/40V Elko capacitator.

Giuseppe Mazzilli postete
So what has prompted the German designers Saba to do so? I think simply the problem of space.

Hello Giuseppe,

this probably also was a question of money. You must keep in mind that the managers in the developement section had to observe certain budgets.
The retail price was fixed by the marketprices of the competitors´ products plus SABA had to yield a little Profit also.

They would have come up with a solution to the space-problem for sure but if a 10.000µF costs € 1,50 more and the budget is exhausted - than that´s it.

BUT, fortunately today capacitors are cheaper and smaller and we do not have to abide to strict budgets.
I replaced the 4700µF in my VS 80 and 8120 by 10.000µF myself and didn´t regret it.
You can keep the original caps in case you want to swap them back some time in the future.

nightbear postete

Giuseppe Mazzilli postete
So what has prompted the German designers Saba to do so? I think simply the problem of space.

Hello Giuseppe,

this probably also was a question of money. You must keep in mind that the managers in the developement section had to observe certain budgets.
The retail price was fixed by the marketprices of the competitors´ products plus SABA had to yield a little Profit also.

They would have come up with a solution to the space-problem for sure but if a 10.000µF costs € 1,50 more and the budget is exhausted - than that´s it.

BUT, fortunately today capacitors are cheaper and smaller and we do not have to abide to strict budgets.
I replaced the 4700µF in my VS 80 and 8120 by 10.000µF myself and didn´t regret it.
You can keep the original caps in case you want to swap them back some time in the future.

Hello Achim,
welcome to the post. But now I forgot that I have added to a topic not posted by me and inserting a new topic out initial discussion. In addition, a discussion is in German while I'm speaking in English.

I apologize for both errors with all of you and ask you if I have to-re post the whole thing into a new topic.

For what you say, Achim, I am in agreement. I know well the question of budget because I worked at Grundig as authorized service center in Rome for several years and i am well informed about the political construction of the equipment! And much just what you say, about the fact that we can now replace the capacitors because they are cheap. I'm considering what is best to do, balancing the need to replace all capacitors of the power supply with the precaution of keeping the ones that are electrically operated and regularly, to maintain the originality of the product to its maximum value. Thanks Achim and please follow me again!

Comparison test between capacitors :

Hello Giuseppe,

Grundig was a quite popular brand in Italy and so was Telefunken.
At the same time, many people in Germany wanted to have a Brionvega TV because of the remarkable design.

For replacing the Roederstein 6800µF I would strongly recommend the Panasonic HA.

Hello Giuseppe,

i would prefer Achim's advice too. The Panasonic HA is of very good quality, and i think for most situations with 10,000 µF sufficient (I don't think you'll use the set for 24 hours party at full throttle).
But if you change the capacitors please be very careful with the big Herrmann rectifier. In my 9241 i changed the capacitors to the next higher value and at the same time i changed the rectifiers. You'll have much higher current in start and the peak current in every wave will be higher. Most of the green rectifiers will not stand that for long (i already had Herrmann rectifiers of that type with a short on one diode too). And it would be a pity if the power supply smokes off some hours after service... Just for safety...

Hello Achim and Gunnar !
I agree with the choice of 2 capacitors Matshushita of 10.000MF / 63V. I will apply those. I'll have to change, even if good, the bridge rectifier of + - 35volts. In fact, the bridge mounted is a B80-C5000/3300 type, which means 80volt (max) and 5A (max).
At this bridge you can apply a maximum capacity of 5000MF = 2.5 A. 2.5 A is the half of 5A, because the other 2,5A will be consumed by the circuit power audio during the conduction of the diodes of the bridge, at maximum volume.
But already only the circuit draws 5A (maximum volume) then this bridge rectifier, such as capacitors, it is underpowered.
Maybe the bridge has never been broken because the volume does not rise much during use in the home. But if it is, you can be sure that the bridge rectifier would warm very much!
I'll have to change with a 10A bridge rectifier and transform the fuse 6.3 AT in 8AT. The fusion of the new fuse 8AT, in case of accidental short - circuit of the power audio line, will be guaranteed because the transformer is a 25Volt / 10A and it exceed the current of the fuses.

Then we will see what to do next!

Achim and Gunnar thanks to you all for attention and passion. See you soon, Giuseppe from ( a hot ) Rome.



This original bridge rectifier can not go well with these capacitors !

Hello Achim, good morning to Gunnar
and good morning to everyone who wants to follow me and help me with their advice with the repair work and restoration of Saba UHC 9941.
While the work on the power board go ahead (but without haste, with the pleasure of doing things right) I'm here now to write something that goes more technical part of the speech.
I'm 49 years old ( next August 25: 50, yes make it !! ), I have worked for 21 years at the authorized support of these brands: Panasonic, Technics, Toshiba, Denon, Sharp, Mc Intosch (audio), Grundig, Revox, Sennheiser, Thorens, Tascam. Still working as chief technician at an authorized laboratory and I love my job, really. Sure, sometimes the problems are so difficult to understand (the digital electronics is full of difficult problems to be investigated) that I want to let go of everything, but with patience and love will solve everything, always.

Having taken care to brand Grundig ( i love German brands ) I attended some Italian forum to share experiences and help.

Never experience was so stupid.

As I tried to talk about technical topics, I felt people open thread about really strange things. They were always talking not about electronic or mechanical problems, but about cable boxes, about construction details unnecessary to lover's knowledge of the Grundig brand. A day a person said that on his Grundig, if unscreweing " a BIT " a screw of the bottom cover, he could hear the sound better! All the other people in the forum were quick to confirm this experience and complimented him! I inserted myself in thread and I told him that, having done service technician for 21 years in Grundig, attending all training audio sessions in Trento ( Italy), I had never heard of these curious topics. I told him that, in my opinion, this is not electronic, but imaginative - electronic. That day I gained more insults than any I've had in my entire life.

Here in the forum Saba I found good people and people who, above all, know what they say. Then today, it's Sunday, I just want to say thanks to Achim and Gunnar for their sincere and well- informed support, as fans, to my work on Saba UHC 9941. I just had to say, and I said. Thank you. Giuseppe from Rome, Italy.