Hi to everyone,
the standby light of my Cyrus 8vs is flashing red, and the amp does not power up.
I've checked all the expected voltages, and everything is ok.
In the "PSU Checker" area (apparently based on IC402, an LM393) I've noticed that the R408 SMD resistor seems to be open. Moreover, that resistor is completely white, with none readable marking on it.
Here attached a picture of the area involved.
Anyone could help me to retrieve the 8vs schematics, or at least the proper value of R408?
Thx a lot in advance to everyone
the standby light of my Cyrus 8vs is flashing red, and the amp does not power up.
I've checked all the expected voltages, and everything is ok.
In the "PSU Checker" area (apparently based on IC402, an LM393) I've noticed that the R408 SMD resistor seems to be open. Moreover, that resistor is completely white, with none readable marking on it.
Here attached a picture of the area involved.
Anyone could help me to retrieve the 8vs schematics, or at least the proper value of R408?
Thx a lot in advance to everyone
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R408 is designated a - SMD0805 with a value of 1M ohm (meg-ohm ) at 1% which are available from various sources including Mouser.
For those not familiar with this resistor coding Stack Exchange a quality engineering website gives an answer-
surface mount - Difference between 1206, 0805 and 0603 SMD resistor - Electrical Engineering Stack Exchange
For those not familiar with this resistor coding Stack Exchange a quality engineering website gives an answer-
surface mount - Difference between 1206, 0805 and 0603 SMD resistor - Electrical Engineering Stack Exchange
Thx a lot Duncan, I will get it.
Any chance to obtain the schematics somehow?
Best regards, Paolo
Any chance to obtain the schematics somehow?
Best regards, Paolo
What a pity... Do you think it's normal that R408 is white, with no markings at all?
The initial power-up cycle is performed properly, power transistors are ok, fuses are perfect, the stand-by button is working...
Where else should I look for the fault?
The initial power-up cycle is performed properly, power transistors are ok, fuses are perfect, the stand-by button is working...
Where else should I look for the fault?
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Its not normal Paolo it should have marking probably burnt off as the wattage is very low .
If the SMD resistor is okay then as you have checked the power transistors -check the drivers also the power supply capacitors .
If okay then you might have a fault in the logistic control but without a schematic its going to take a while .
I have a Cyrus XTSE with additional power supply , if you know somebody locally with a PSX-R you could try plugging it in to see if it makes any difference .
I will keep looking for a schematic .
If the SMD resistor is okay then as you have checked the power transistors -check the drivers also the power supply capacitors .
If okay then you might have a fault in the logistic control but without a schematic its going to take a while .
I have a Cyrus XTSE with additional power supply , if you know somebody locally with a PSX-R you could try plugging it in to see if it makes any difference .
I will keep looking for a schematic .
Eventually, I've found the culprit.
Inside the "PSU checker" area the C400 capacitor (22uF/50v) was defective. I've warmed up that area and the amp magically started. Cooling the capacitor again, the failure returned.
A classic stroke of luck.... anyhow, I hope it can help someone other.
A lot of special thanks to Duncan, who supported me so patiently
See you next time!
Inside the "PSU checker" area the C400 capacitor (22uF/50v) was defective. I've warmed up that area and the amp magically started. Cooling the capacitor again, the failure returned.
A classic stroke of luck.... anyhow, I hope it can help someone other.
A lot of special thanks to Duncan, who supported me so patiently
See you next time!