Concept 2.5 score (Kind of...) Help.

[msabol]

I recently got a Concept 2.5 for $10 at the local Salvation Army. That is the good news. But I have discovered 24vdc on the left channel while checking the DC offset. :tears: I have spent a little time looking for resources on the Concept line and I have found some info but no service manuals for the 2.5. Can any of you point me in the right direction? I'd really like to fix it and give it a listen. Thanks for any help.

Mike

[mea2112]

Don't give up yet. I'll take a look at my Concept 2.0 and 3.5 and see if I can remember which pots, if there are any, are for adjusting the DC offset.

[msabol]

Wow, thank you. That would be great. How do you like your Concept recievers? Are they still in your set-up rotation?

[mea2112]

They're excellent receivers in my opinion. I really don't use them very much but I just like them too much to let them go.
You're right about the lack of information on the Concept line. I couldn't find one place that has any service manuals for any of the Concepts.
Are you sure about the reading you got on the left channel? What did the right show? You're sure it was 24 volts and not millivolts right?

[bully]

Try the Yahoo! group for Concept gear. I believe there was some recent talk about a SM for the 2.5 and that someone had one. Most of the guys in the group are former Pacific Stereo techs and, like me, really love the gear.
My monster 16.5 is simply the best receiver I've heard (though I haven't heard the CR-3020, but have a lot of Yamaha gear).
Everything I've read about Concept receivers is that they are clean, well-designed and very well built.

[msabol]

Thanks for the general Concept encouragement, fellas.

mea2112 -- I am sure about the measurement. There is something wrong downstream, a blown output transistor or a direct short from some other component. Doing the fix doesn't scare me I just need to get the info on the layout. I don't have enough experience to fly without at least a schematic. (the other channel has 0.8mv)

Bully -- Thanks for chiming in. I am a member of the Yahoo group, as well, but I was hoping I might find some luck here at AK. It was worth a shot. I'll just wait until Mike George gets his microfishe digitized before I go any further.

Thanks again guys!!!

[mea2112]

Hopefully, someone can help you out with the service manual. I took a look at my 3.5 and there are several adjustment pots. Unfortunately, I couldn't determine which ones, if there are any, are for DC offset adjustment. Sorry I couldn't be of more help.