Roadster Channel One OUT

[thetragichippy]

Question,

Channel 1 in my roadster went out right before a gig this past weekend. Someone brought it in off the truck, so I'm not sure if it was sat down hard. All I know is everything works 100% except channel 1. Any ideas? The amp is about 2 years old and I think it is original tubes. And .....if it might be a tube, should I change all tubes because of it's age?

Thanks

 

[easchow]

V2 A = 3rd Gain Stage - CH 1 & 2

If you have a problem in one specific mode or channel, it's most likely a pre-amp tube problem. Try swapping out your V2 A pre-amp tube.

If that doesn't work, you can always call Mesa Customer Service and they can walk you through the troubleshooting:

US Domestic Support: (707) 778-6565

 

[mansfieldguitars]

Channel one signal flow starts out from input jack to V1A. From V1A to channel 1 tone stack, then channel one gain pot and then to inout 0f V1B. Since all channels use those same tubes that would rule them out. My guess would be a broken wire or component in the tone stack or on the gain pot or something with the relay switching. RYD1 is the relay to check. In channel one the relay is engaged by completing the circuit to ground through the channel selecter switch and that relay determins if the signal is routed to channel 1 or channel 2. In channel 2 that same relay os off. RY1C relay switches between channel 1 and channel 2 master volumes. There asre some other relays involved but hopefullly theis will solve your issue. If not we'll need to dig deeper but if under warranty you might as well let mesa reoair it for free. Hope this helps.

If you need more help just let me know.

Thanks
John

 

[thetragichippy]

Thanks for the replys.....looks like I'm calling mesa.....