Troubleshooting Problems

Fixing-up any old gear

Started by vansinn

Pages1 2

Replies: 15
Views: 14,981

February 15, 2017, 10:27:25 AM
by DannyjoeCarter

MP-1 no display or LED's

Started by andtimebegins

Pages1 2 3 ... 5

Replies: 70
Views: 11,315

February 09, 2021, 06:36:21 AM
by Iperfungus

No Power, No Display, No Output

Started by Chip Roberts

Pages1 2 3

Replies: 38
Views: 16,878

December 23, 2017, 08:35:04 AM
by MarshallJMP

MP-1 got Noisy...

Started by rabidgerry

Pages1 2 3

Replies: 34
Views: 17,220

July 02, 2017, 04:53:43 PM
by MarshallJMP

Viper probs, info moved from Schematics section

Started by guitardude57

Pages1 2 3

Replies: 32
Views: 15,034

June 02, 2017, 03:28:21 AM
by MarshallJMP

ADA mp1 - Solid States works only

Started by gg85

Pages1 2 3

Replies: 31
Views: 4,150

October 05, 2023, 11:42:29 PM
by rnolan

MP-1 A channel much quieter than B

Started by Mxzx

Pages1 2 3

Replies: 31
Views: 15,600

February 12, 2014, 06:32:21 PM
by El Chiguete

Sound issues after noise mod

Started by Deregorn

Pages1 2

Replies: 29
Views: 14,595

June 19, 2014, 02:41:35 PM
by MarshallJMP

Rack grounding?

Started by Georgeclooney0

Pages1 2

Replies: 29
Views: 8,921

December 04, 2018, 11:07:57 AM
by rabidgerry

MP1 V2 (no top switch) All original excluding battery mod

Started by ScottGray

Pages1 2

Replies: 26
Views: 5,537

October 18, 2020, 11:03:11 AM
by MarshallJMP

MP2 Volume drop

Started by Shredzilla

Pages1 2

Replies: 25
Views: 13,314

July 27, 2014, 12:23:00 AM
by Shredzilla

No lights, no display, no sound

Started by emunstar

Pages1 2

Replies: 25
Views: 8,895

March 04, 2020, 11:42:35 AM
by MarshallJMP

MP1 No Overdrive/Distortion

Started by Billy Penn

Pages1 2

Replies: 23
Views: 12,059

July 12, 2016, 06:38:00 AM
by rnolan

MP-1 volume drop

Started by revhed666

Pages1 2

Replies: 21
Views: 10,814

May 20, 2016, 08:24:13 AM
by Harley Hexxe

[Solved by MarshallJMP] MP1 doesn't start up - mysterious blinking

Started by hal2000

Pages1 2

Replies: 21
Views: 13,884

January 27, 2014, 10:03:05 AM
by MarshallJMP

MP1 Tube board issues, like am radio

Started by monty

Pages1 2

Replies: 20
Views: 13,226

January 22, 2016, 12:35:39 AM
by tomy

No lights No sound and a hot ic

Started by t-rack

Pages1 2

Replies: 20
Views: 11,062

April 28, 2015, 02:38:42 AM
by MarshallJMP

MP-2 After the noise mod - Spanky Clean is distored . . .

Started by W.Laturno

Pages1 2

Replies: 19
Views: 11,703

June 16, 2014, 05:14:37 AM
by rnolan

Extreme hiss and microphonic V1 tube circuitry

Started by NeverAfter

Pages1 2

Replies: 19
Views: 10,695

May 06, 2016, 10:33:18 AM
by rnolan

Battery Issue in MP-1

Started by kfowler8

Pages1 2

Replies: 18
Views: 15,299

March 27, 2015, 01:07:53 PM
by MarshallJMP