Lone Star version 2 issues

Classics and Specials

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edge59
Mark I
Posts: 43
Joined: Tue Jun 12, 2007 11:14 pm

Lone Star version 2 issues

Post by edge59 » Tue Apr 09, 2019 12:06 pm

Hello, I just bought a Lone Star Classic version 2, 2013 in excellent shape but when I plugged in and switched from Tweed to Full power the amp stared humming so I shut it down and checked the power tubes, the 2nd power tube in from the tube rectifier side phenolic key pin was broken off and the tube was inserted, off by one pin. The seller said everything "is in top running order, no need for tubes, ready to go". I reinserted the tube with the right orientation and all seemed better, no hum anyway. The Solo feature does not work in Tweed mode (yes the loop is engaged), only in full power mode, it works (the LED on the foot switch seems to be fine but the Solo volume does nothing, possibly the relay?) .. I pulled the rear top pcb out and the power tube PCB and seen a burn mark on one of the relays nearest the rectifier tube. Also there are 2, 360 ohm high wattage (black) resistors on that board also near the tube rectifier, one reads 360 ohms, the other is reading dead short, so I pulled one end of the resistor from the circuit and took another reading, and it reads 360, so not knowing and having a version 2 schematic I am lost. I have the version 1 schematic but these parts are not on it, I believe its to do with the 10 watt class A circuit possibly. I dont want to send to mesa to repair if I can do it myself as I do repair tube amps all the time but without a schematic for this would be difficult, the only way I can figure what things are supposed to be. I am going to contact the seller and ask for a partial refund (I know, good luck right?). Anyone have a version 2 or had this issue?

Thanks,
Ed

edge59
Mark I
Posts: 43
Joined: Tue Jun 12, 2007 11:14 pm

Re: Lone Star version 2 issues

Post by edge59 » Tue Apr 09, 2019 4:00 pm

So far I have a bad relay on the power tube/rectifier pcb silk-screened RYF/H. Does anyone have a version 2 schematic so I can check voltages and get this amp up and going for an upcoming gig this month? It's a 2013 LSC with 100/50/10 watt settings.

Thanks! Ed

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