well  i used the a1m log pot on the gain and the b5k linear on the overdrive volume and it works fine. thanks for the help everyone i appreciate it . so it only cost me 20 dollars. i paid 15 bucks for the amp and 5 for the pots .

Quote from: Enzo on January 31, 2013, 04:05:29 AM
Then that is where it starts.  We verify the thermal sensors are turning off the power.  And if so, why is the amp getting hot.

cant figure it out yet.

Quote from: Enzo on January 30, 2013, 01:10:48 AM
OK, so you mean it literally shuts off the power - no lights noi activity - as opposed to just losing sound?   In that case, no, I don't think it is the tube.

REach up under the chassis and feel it when it shuts down, is the chassis HOT?  A thermal sensor turns off the mains power to the amp when it gets too hot.   That allows the amp to cool, and after a few minutes it cools enough to come back on.   So we need to know if it is heating.

yeah it shuts down no lights or activity. the chassis was pretty warm .

Quote from: Enzo on January 30, 2013, 12:22:57 PM
Harder to find???

Marshall, like all the other factories, has their pots made for them.  Which taper they get is a simple matter of which one they ask for.  The schematic specifically calls for the audio on the clean channel and the linear on the dirt chanel.  This is not because Marshall couldn't find them, it was designed that way.   I'd stick with the linear it came with, unless I found the control did not operate smoothly in terms of function.

Oh yeah one more thing .the gain pot was a G1m i know its a 1m . I have a A1m log. pot will that work ? I couldn't find a G1m anywhere

Quote from: Enzo on January 30, 2013, 12:22:57 PM
Harder to find???

Marshall, like all the other factories, has their pots made for them.  Which taper they get is a simple matter of which one they ask for.  The schematic specifically calls for the audio on the clean channel and the linear on the dirt chanel.  This is not because Marshall couldn't find them, it was designed that way.   I'd stick with the linear it came with, unless I found the control did not operate smoothly in terms of function.

oh ok . That's what I thought, just making sure. Thanks alot for the help. I appreciate it.

Quote from: DrGonz78 on January 30, 2013, 09:13:40 AM
It's a cheap lil Marshall practice amp and I remember replacing some broken pots on that amp. That was the 3rd amp that I bought to fix. Sure a Log is much better for Gain and Volume type controls but on this amp it really does not make all that much difference. I have all these pots still too... I went to Tayda for replacements... $1 pots free shipping! For this amp that is what is practical. I am sure they have the Log version of that pot, but if they are harder to find then that explains why it is linear.

I ordered some pots from tayda on there web site. they were only 50 cents each.but the min. purchase is 5 dollars .so i ordered like 10 different pots  they do sell on ebay but there 99 cents. i ordered 2 log and 2 linear 5k yeah i didnt think it would matter much which one i used.

i picked up a used marshall mg10 amp. the 2 volume pots  and the gain pot were broke and need replacing. the clean channel volume had a 5k log. pot .A5k . gain had a 1M but the volume on the overdrive channel had a 5k linear pot B5k. shouldnt it be a log. pot  on the overdrive volume ?

I have a fender roc pro 1000 head . powers on works for 20 minutes then powers down .if i wait ten minutes and it will power back on it keeps doing this . could it be the tube ?
Anybody have any ideas on what it could be