I don't know if this is the right place to post this but I'm having some trouble with a primare pre 30. I doesn't seem to power up : no display at all, not even the standby indicator. When I power it on nothing happens. I checked the power supply and I have all the correct voltages on the different rails. There doesn't seem to be any schematic out there and I don't really know where to look next as I'm used to older gear. Just in case I verified and all the IC's seem to be still available in case some are bad. I just need a place to start.
Any help would be very welcome
Any help would be very welcome
Just repair a Primare integrated and the symptom was the same, not powerin up. Cause was DC offset on one channel. The primare are pretty close to Passlabs usual preamp circuit using k170 jfet input. However they use an op-amp to convert balanced to SE input for the K170. Preoblem on mine was a defective input opamp, caused probably by my friend tube phono preamp.
I think that maybe the phono preamp let some higher voltage going throuht the output, probably at startup, and blew the opamp.
Check around and compRe both channel near the output, if there is relay, and there are there probably for mute anyway, they are also use for protection.
Check and maybe one channel as huge dc offset, near 10-15v. If that the case, that's your problem, back track until you have no dc offset, maybe the first opamp like me...
SB
I think that maybe the phono preamp let some higher voltage going throuht the output, probably at startup, and blew the opamp.
Check around and compRe both channel near the output, if there is relay, and there are there probably for mute anyway, they are also use for protection.
Check and maybe one channel as huge dc offset, near 10-15v. If that the case, that's your problem, back track until you have no dc offset, maybe the first opamp like me...
SB
Hi SB!
Glad to hear that you fixed yours.
On the input opamps I seem to have only + and - rails, the other pins are at 0v. I do have a little difference in offset at the output rca plugs on the right channel but only of about 48mV (3mV for the left channel). It's quite hard to trace things back without a schematic, do you know if there is one available somewhere ?
I noticed the pads are very delicate !!!
Glad to hear that you fixed yours.
On the input opamps I seem to have only + and - rails, the other pins are at 0v. I do have a little difference in offset at the output rca plugs on the right channel but only of about 48mV (3mV for the left channel). It's quite hard to trace things back without a schematic, do you know if there is one available somewhere ?
I noticed the pads are very delicate !!!
Got it thank you very much. Now I'll just have to find my way in all this (I'm used to much older gear).
Still looking for people that can help in the right direction
I see there is a "flash download" port, can this help in any way to diagnose it and if yes how do I proceed (I don't have any programming tools)
Still looking for people that can help in the right direction
I see there is a "flash download" port, can this help in any way to diagnose it and if yes how do I proceed (I don't have any programming tools)
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Hi again (looks like I'm talking to myself here)
For those who might have the same problem some day, the culprits were U2, U3 and U13, all 3 of them were dead. I got them replaced and installed the new ones with some sockets (they were soldered directly to the board and were a pain to get out) and now everything seems to work okay. That is if I don't count the huge dc offset when I push the on/off switch on the bottom. when I switch it ON I get my power meters on my Pioneer SA-8800 all the way up (with speakers disconnected) and when I switch it to OFF the protection relay of the amp even kicks open. Once its on I can turn it out of standby mode and it works perfectly.
I got this far but once again, some help would be very welcome !!
For those who might have the same problem some day, the culprits were U2, U3 and U13, all 3 of them were dead. I got them replaced and installed the new ones with some sockets (they were soldered directly to the board and were a pain to get out) and now everything seems to work okay. That is if I don't count the huge dc offset when I push the on/off switch on the bottom. when I switch it ON I get my power meters on my Pioneer SA-8800 all the way up (with speakers disconnected) and when I switch it to OFF the protection relay of the amp even kicks open. Once its on I can turn it out of standby mode and it works perfectly.
I got this far but once again, some help would be very welcome !!
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