Raven PMB repairs?

[M Hayden]

Since Steve Rabe is retired, is there anyone repairing Raven PMBs?
Need to get a switch replaced on one.

[sdelsolray]

Sent you a PM.

[Voxbox30]

Anyone got a schematic?
I'm an audio electronics engineer in the UK and just got one of these last week. Unfortunately none of the ICs have their IDs as they have been sanded off. All probably standard chips like TL072s given the vintage of the preamp.
I'd really like the schematic so I can repair it in the future.

Can anyone help?

Cheers, Colin

[hess]

Originally Posted by Voxbox30

Anyone got a schematic?
I'm an audio electronics engineer in the UK and just got one of these last week. Unfortunately none of the ICs have their IDs as they have been sanded off. All probably standard chips like TL072s given the vintage of the preamp.
I'd really like the schematic so I can repair it in the future.

Can anyone help?

Cheers, Colin

Yeah unfortunately the op-amps in all of the Raven Labs gear have their markings sanded off. The good news is that the Raven labs circuits are fairly easy to trace. I’ve never been able to find the schematics but from my own tracing of the PMB, it appears Steve Rabe borrowed heavily from his SWR Cali Blonde pre and tone sections which do have schematics and use TL072 op-amps throughout. That said, for various reasons I believe he used a combination of TL072 and AD823 or OPA2134 dual op-amps in his Raven Lab designs.

[hess]

Originally Posted by M Hayden

Since Steve Rabe is retired, is there anyone repairing Raven PMBs?
Need to get a switch replaced on one.

Should be something any electronics tech could handle.

[Voxbox30]

Originally Posted by hess

Yeah unfortunately the op-amps in all of the Raven Labs gear have their markings sanded off. The good news is that the Raven labs circuits are fairly easy to trace. I’ve never been able to find the schematics but from my own tracing of the PMB, it appears Steve Rabe borrowed heavily from his SWR Cali Blonde pre and tone sections which do have schematics and use TL072 op-amps throughout. That said, for various reasons I believe he used a combination of TL072 and AD823 or OPA2134 dual op-amps in his Raven Lab designs.

Thanks Hess, thats good info on the chips and CaliBlonde.
Yep it should be possible to trace, but its work I'd rather not have !
Some of the chips have an "X" marked on them - any ideas?

Cheers, Colin

[hess]

TL072 op amp

[dsulliman]

Hey, I have repaired 3 ravens for other players recently. One of them was an intermittent mute switch & all 3 got a 9V retro power supply modification i came up with the help of Mark Erellis testing. You can now use any standard Boss style 9v adaptor 300mA reccomended. His power supplys failed - (they all do aparently) and i had an idea & we worked it out with real live show results last week. Im new to this social media thing just started an istagram and working on website ect. I figured this place was a good place to find folks with the same desire Mark had and figured Id let you know. contact me @ 98audio.com & ill help you out.