So I got this amp, its a Monoprice 15 watt tube amp thats suppose to be modeled just like the Laney Cub12R I think.
I got the schematic for it. I was just wondering if anyone could help me ID this resettable fuse. And where can I find a replacement?
Laney calls it Laney PN 007390
the schematic also calls it PTC6.0
I looked the part up on ebay and found one that calls it a pollyswitch resettable 30V 6A fuse.
Is that what this part is? It was just jumpered when I got it. I want to replace the jump wire with the correct part. What do you guys think?
Re: Monoprice 15 watt tube amp problems
Posted: 07 May 2018, 00:49
by chuckusa
So the story went this amp was plugged in and running when a hair dryer was plugged into the same socket outlet and something in the amp popped.
From what I can tell after the amp popped,
these things were attempted to be replaced:
R2 and R12
F1 PTC6.0
250v glass fuse
What do you guys think? How bad is she? Will she live? Lol...
What I want to know is where can I find the two replacement fusible resistors and are they just plain ole 1/2 watt fusible 1k resistors?
what is that part thats been replaced with the jump wire, is it called a PTC6.0 resettable fuse? Where can I find one?
Where can I get these 3 items from? and whats their exact name and values ect, so I know im getting the right stuff....
Please refer to the pictures underlining info for details on each component.
Re: Monoprice 15 watt tube amp problems
Posted: 07 May 2018, 03:05
by chuckusa
I found the what I believe is a resettable fuse.
It came from where that jump wire is located.
So with the right mentioned parts replaced, do you guys think this amp will come back to life?
Im wondering if R2 and R12 are 1k half watt fusible resistors
and if F1 is a 30v 6A resettable fuse.
I want to replace these parts then pop a new glass fuse in her and see if she boots up lol
Re: Monoprice 15 watt tube amp problems
Posted: 07 May 2018, 18:46
by chuckusa
Oh yea also it wasnt a hair dryer that was plugged in, it was an old electric heater.
Re: Monoprice 15 watt tube amp problems
Posted: 08 May 2018, 19:58
by chuckusa
Sys mods please delete this entire thread, thanks. Sorry.
Re: Monoprice 15 watt tube amp problems
Posted: 15 Jun 2018, 10:03
by modman
chuckusa wrote:Sys mods please delete this entire thread, thanks. Sorry.
Why? This thread could help out others in the future...
Would be nice to share the schemtic too
The PCB on this amp looks identical to the Laney LC15.
I had one in to fix recently with an intermittent resettable fuse in the heater supply (same position on the PCB as this one). Apparently there was a bad batch of resettable fuses that were made in Mexico.
Replacement with a generic 6A 30V Chinese one (or a wire link) is the recommended cure. As it was for a customer I fitted another.