Rotel RSP 1098 - noise and no sound from digital - probably CS494003-CQ is defect

[Piotr07]

Hello All.
I need technical informations from users or technicians who know this problem in the RSP1098 .
If someone knows this problem of DSP CS494003-CQ please send my a details of the necessary modification/ repair.

Regards
Piotr

[mjb]

Try searching the forums, I seem to remember this coming up a long time ago... As I recall, the reed-relays go bad (with age), and causes the problem you describe. Its not a DSP problem. Pretty sure Rotel will repair it too.

[windshear]

Have you tried a processor reset? Sometimes they go bonkers.

[Piotr07]

Thanks Mike for your answer. I'll try to find which relay is the reason.

Best Regards
P.

[Piotr07]

Are you sure that reed relays type A12W-K is the problem ?
I suspect that the main problem with the DSP concerned the two 24V relays from PSU board , these relays supply regulators +5V for CPU and DSP boards .In later versions (after 2003) RY1,RY2 have been replaced by a stronger from OEG and add four 10nF/500V for spark suppresion.

Next question. Is it normal that heatsink of regulators IC7,IC8(2*KIA7805) is very hot ?

[mjb]

Are you sure that reed relays type A12W-K is the problem ?

I can't promise, but I know the relays lose their springiness and don't make good contact, or open properly.

Next question. Is it normal that heatsink of regulators IC7,IC8(2*KIA7805) is very hot ?

Not sure. The whole device runs warm as I recall. Perhaps you should replace them with an LM7805 (1A5 instead of 1A).

Good luck!

[tetzschner]

Hi Piotr, did you manage to locate the failure? I'm having the same problem with digital audio comming and going. Also I hear some relay clicking.

By the way I don't think changing the regulators would solve the heat problem. The regulators are linear and are supposed to get hot when loaded.

Best regards, tetzschner

[Piotr07]

tetzschner - I solved my problem after replacing RY1,RY2 . But if you have version after 2003 y you may have newest relays from OEG which should be stronger .

[tetzschner]

Hi Piotr, thanks for answering. I don't know the model year, but I'll check the relay type tomorrow. In my case the digital audio playing fine but suddenly it comes and goes. I have not tested the analog audio yet.

[Piotr07]

How to check the current software - in this way you can specify the year.
Press & hold MUTE on the remote or the front panel for 5 seconds. The currently installed software version will appear on the front panel display of the unit

[tetzschner]

I'm not the first owner of this receiver and have allready upgraded the firmware. However the relays was of the old DEC type. I've ordered the OEG according to the service manual (and some 10nF 500V). So in a week or two I'll know if the problem is solved 😊

[Piotr07]

DG2SU type from DEC(China quality) were too weak . You can check by tapping on the relays if will be some change or other symptoms .

[Lex]

Hey welcome to the forum you new comers. With the quality of this exchange, it seems this is the place to be for Rotel info still... Good luck with your components guys.

Doug

[tetzschner]

OK, so changing the old DEC relays did not solve the problem. In my 5.1 setup there are static ticks in the center speaker approx 1% of the time. All audio channels totally comes and goes between 0-5 times pr minute. The on and off times varies. I hear a relay clicking when the audio cuts off and a click when the audio comes back again. Also the displays shows the audio-mode when this happens. When waiting for the problem to occur the receiver plays fine for more than 15 minutes... typical 😕

[tetzschner]

After 20 minutes on standby the problem is back again. This time I tested the analog CD input. When the problem occurs the output is more than 50% statics ticks on all speakers and it is hard to identify the real audio behind the noise. This time the optical input is mostly cut off and my guess is when the optical audio is cut off, the CD input has the problem described.

[tetzschner]

Funny, for the last couple of days I was not able to reproduce this fault. It only happened the first 3 times (after installing the new realys) I powered up the receiver, and lasted for approx 5 minutes each time. Could it be that the newly installed relays has some dirt or coating on the contacts that needed to be burned away... like some kind of burn-in? They where brand new but I can't tell how they where stored before I got them.

[mjb]

Thats good to hear. Did you by chance take some pics while it was all apart? I'm sure your experiences might help someone else.

[tetzschner]

I should have. It took me more than one hour to do changes the relays. Almost every part must be dismounted before gaining access to the buttom of the power-pcb.
But the problem is still not solved. Shortly after my last post the problem was back again.. typical The issue is that when I listen to the optical input (I'm not using analog inputs, only optical) a relay clicks and the sound disappears. After some times, a few seconds or few minutes, the relay clicks and the sound is back again. This could happens over a longer period. But after connecting a CD-player to the analog CD-input, I tried to switch this input. The sound was very very bad. Lots of static noise and only a little music. Last time this problem occured (when listen to optical-input) I tried to power off and on the receiver but this did not slove the problem. But when I toggled between optical and analog-CD-input the problem disappeared for the rest of the evening.

[Piotr07]

Mike mentioned about the reed relays that they also cause problems . Try again

[tetzschner]

According to the service manual, there are no reed relays. There are mechanical relays and analog switches. But there are a switch between DSP and analog audio that have my attention. But at the moment there could go days without failure, so it ain't easy to locate the issue. Anyhow I'll will give an update when I'm getting closer to the problem, if somebody could find this useful.

[windshear]

Maybe try a bottle of freeze spray on certain parts of the circuit to isolate where the problem is and if its temperature dependant.

[windshear]

Maybe try a bottle of freeze spray on certain parts of the circuit to isolate where the problem is and if its temperature dependant.

[Wardo]

According to the service manual, there are no reed relays. There are mechanical relays and analog switches. But there are a switch between DSP and analog audio that have my attention. But at the moment there could go days without failure, so it ain't easy to locate the issue. Anyhow I'll will give an update when I'm getting closer to the problem, if somebody could find this useful.

Did you ever find the problem?