Amp cutting out

[Abe]

I have an '87 Marshall JCM 800 2210 100W half-stack, and at unpredictable times it just cuts out completely, then cuts right back in a few seconds later. This can happen regularly for a few minutes or not at all on some days, it's extremely frustrating and very unpredictable.
The head doesn't seem to be affected at all and so I would assume that it would be a fault with the lead connecting the head to the cab or possibly something wrong with the cab.
If anybody has had a similar problem or has a clue about how to fix it, any help would be much appreciated.

[Alan Moorhouse]

I once had a similar problem with a Laney valve PA head, which would cut out and back in - the problem turned out to be the mains connector slightly loose in its socket. Every time I did the pogo, the plug came loose. A new mains lead did the trick - I should have known better than to pogo at my age!

[Raskolnikov]

it definately sounds like something is loose

[James]

I've had some experience with amp problems. It could be that the socket is loose, you could test this by wiggling the input around a little when it cuts out. But in my completely non-expert opinion, it sounds like the capacitors, in which case you need to take it to a tech to get it fixed.

[skee1]

You might try a pickup & electronic cleaner on the,
input connections.
I carry a pick-up & electronic cleaner with me when i,
go out on the road.
Its made by (Electro-sound) i just had to spray into,
the inputs of one of my fender amps the other day.
It was humming plus cuting out and in.
Ask your music store about it its a life saver.
Most of this is caused by dirty contacts,from dust ect.
Also on one of my fender amps the silver box down,
in the bottom of the amp that controls reverb ect had,
dirty contacts also which i had know reverb untill i,
sprayed into the inputs in it.

hope this helps Mark

[Lordathestrings]

You can narrow your search a bit. If the sound fades out and then fades back in, you're probably experiencing a problem with the power cord. Check the plug for damage, and then carefully inspect the cord all the way back to the amp.

If it cuts out and back in with no change in volume, its probably a loose connection somewhere in the signal chain. Take a close look at your cables, and wiggle the plugs and jacks.