Problem with DC-5 :(

[blacklight_uk]

Hi guys, went to practice last night and turned on my DC-5. The power light flashed and then went out straight away. I tried a few more times and im not getting anything! I unplugged it and swapped out the fuse on the plug for a new one and still nothing. I'm thinking it might be the slow blow fuse in the amp so I took it out and ordered a new one.

Since then though I've been worrying it might be something else. The manual says that the most common cause of a blown fuse is power tube failure, but my amp isn't turning on at all! I'm just really worried that there's more to this than an inexpensive fuse, but i had been playing it at a gig the night before and it was fine!

Can anyone shed some light?

Thanks,
Josh

 

[cb101]

Sounds like a power tube. If there is a short in one or both of the power tubes that's the reason the fuse blew in the first place. It's also possible you unseated the tube when moving it at your gig. Just replacing the fuse won't get her started again if you have a power tube problem. Change out the power tubes and then put in a new fuse. They use 2.5 amp slo-blow.

 

[tetsubin]

If it's an export model, which is what I'm guessing since you're in the UK, it needs a 1.25A slo-blo fuse. Or at least that's what it needs in Germany with 230V.

 

[blacklight_uk]

Hey guys thanks for the replies. I noticed when i was looking at the amps innards that one of the power tubes had come unseated. I don't know whether that happened before i took the chassis out or not though.

Odd, the fuse in the amp (which i haven't touched before) was a 4A 250V slo-blo. Should i just replace that or go with a 1.25 A?

Thanks again for your help [] I love this amp and want it to last forever!

 

[cb101]

Don't replace it with a 4.0 amp. Use the correct fuse which is, as tetsubin stated, 1.25 for 230V circuits. If you use a 4.0 amp fuse the amp will not react fast enough if something goes wrong internally or with your power source and could cause serious damage.

 

[blacklight_uk]

Wow. I feel really annoyed with the guy i bought the amp from now, but i should have checked it was the right fuse when i got it. There's a moral there :shock:

I've just ordered 10 1.25A fuses to keep just incase. Got them really cheap too

I also ordered one Mesa 12AX7 (incase it's a preamp fault) and a pair of JJ 6L6s. Can't wait to get them in there just so i know either way. This thing is making me very worried! Unfortunately i'll have to wait though as there are no shops near me that stock tubes.

Strangely the other guitarist in my band has a problem with the tubes in his twin. One power tube went bad so he asked me to order him two new Sovtek 5881s. That was only the day before my amp blew.

You know what they say about women who share houses. Maybe it's the same with amps :lol:

 

[tetsubin]

Just to reassure myself I checked the schematic of the DC-5 and for the export version (220 to 240v) it's a 1.25A fuse; for the US version one with a rating of 2.5A. Both slo-blo.

 

[blacklight_uk]

Oh cool thanks tetsubin

I saw that it says 1.25A above the fuse cap but the actual fuse is a 4A one. I don't know who fitted it, but i'm pretty annoyed. Nevermind, i'll make sure it's done right this time.

 

[blacklight_uk]

Well i replaced the old Boogie power tubes with new JJs and replaced the fuse with a 1.25A slow blow. The amp sounds great [] There seems to be much more life in it with the new tubes. We played two gigs on Friday night and at the second gig i was loud enough for the rhythm channel to be just on the verge of breakup. It just sounded amazing, the best tone i've gotten out of it so far! The sound guy commented on my tone and then said "but hey it's a Mesa, you can't go wrong!"

I think he must be a wise man :lol: