Solid State Guitar Amp Forum | DIY Guitar Amplifiers

Solid State Amplifiers => Tubes and Hybrids => Topic started by: Psabin8951 on September 03, 2025, 01:32:44 PM

Title: Laney LC30 blowing HT fuse
Post by: Psabin8951 on September 03, 2025, 01:32:44 PM
I have a Laney LC30 Mk1 which blows its HT fuse as soon as it comes off standby.
I have tried with all valves removed and it still happens.
Fuse stays intact with output transformer unplugged however. Is this likely to be the culprit?
+/- 15V present from Regs to all ICs.
No damaged tracks on the boards.
I can only find a mk2 Schematic online which makes things more tricky.
Any pointers appreciated.
Title: Re: Laney LC30 blowing HT fuse
Post by: Jazz P Bass on September 03, 2025, 07:06:35 PM
It does appear that the OT is bad.
Title: Re: Laney LC30 blowing HT fuse
Post by: Psabin8951 on September 05, 2025, 09:37:40 AM
Confirmation. New output transformer and all good ty!