Hartke blowing fuses

[paulypbass]

Bascily i was at band practice last night and pulled the speaker cable out the head for a secound while it was still running stupid thing to do i no. as i put the cable back in it arcked on somthing and blew the fuse. iv tryed two more fuses now and it keeps blowing them, any ideas what i could of done, taking it to a repair man tomorrow but hopefully its nothing pricyy,

[bertbass]

If your amp is solid state, it's highly likely that you have shorted the output of the amp when you plugged the lead back in, hence the arcing. The first contact in the jack socket could have shorted the barrel and tip of the jack plug. If it's a valve amp, then you may have burnt out the output transformer. Valve amps do not like no load. I fear a hefty repair bill may be coming your way. I hope I'm wrong and it's something simple.

[Mr. Foxen]

If you plugged in a ss amp like, you might have shorted the output with the jack, which might have toasted the output transistors, or associated components, which would make it blow fuses. Briefly unplugging a valve amp is unlikely to actually kill an output transformer, they need a bit of time to do real damage.

[icastle]

Well if it's an HA5500 I don't really think you've done too much damage.

The HA5500 is a ss amp with a valve pre-amp, so no real damage if run without a load.
It has a protection circuit built in (that delay followed by a 'click' a few seconds after switching on before the amp fires up) which 'should' have protected the amp from major mishap.

I'm guessing here, but did you replace the fuse with the right type?
Take a look at the fuse you took out first time round - if it says 'T6.3A' then you need to use a T6.3A fuse - not an F6.3A.
If you try using an F6.3A as a replacement for a T6.3A then it'll blow as soon as you power it up.

[JTUK]

I'd follow the pointers here and check the fuse is rated properly and correctly.
You should never plug in a can to an amp under power but as its SS the fix should be relatively cheap
with a decent tech.

Fuses don't blow for no reason so make sure they are the right ones ---and you have spares--
and get it checked out straight away so you can get to the route problem

[paulypbass]

Right well the fuse that blew in the amp the first time was a 250v 6A it says on back of the amp it takes F6AL/250V the fuse i got from maplins are 250v 6.3A would that make any differance.

The only other thing i forgot to say was the one of the output jacks for the speaker cable is louse. although its been like that for a week now and i used it twice like it.

I'm hoping it wont cost to much money to repair iv been the recomend the guy from a couple of poeple and been told hes good.

[paulypbass]

How hard is it to gets part for hartkes atm. The repair man said it may be hard to get parts. Is there anywhere u can get a wiring diagram

[icastle]

[quote name='paulypbass' timestamp='1334080447' post='1610678']
How hard is it to gets part for hartkes atm. The repair man said it may be hard to get parts. Is there anywhere u can get a wiring diagram
[/quote]

The parts are pretty generic but if you want to be totally sure then you need to order from the Hartke importers:

Korg (UK) Ltd
01908 304670 (Opening Hours 10am - 3pm, Mon - Fri)
Email: [email="[email protected]"][email protected][/email]

Not sure how difficult it is to get a circuit diagram, but, as it's a discontinued model, I guess the Korg service guys will be able to supply one of those as well.

[icastle]

[quote name='paulypbass' timestamp='1334052402' post='1610035']
Right well the fuse that blew in the amp the first time was a 250v 6A it says on back of the amp it takes F6AL/250V the fuse i got from maplins are 250v 6.3A would that make any differance.
[/quote]
Nope.
Those fuses will be fine.

[quote name='paulypbass' timestamp='1334052402' post='1610035']
The only other thing i forgot to say was the one of the output jacks for the speaker cable is louse. although its been like that for a week now and i used it twice like it.
[/quote]
That sounds like a very good place for your repair guy to start looking - could be that the socket is shorting out on something it shouldn't be able to touch under normal conditions...

[paulypbass]

Ok guys thank you very much for all your help. the guying looking at it said he will get bck to me by the weekend and hopefully have an answer so i wil update

[paulypbass]

Spoke to korg today. they were really helpful sent me a wirirng diagram for my repair man to look at and said they can stock transitors, risistors etc for my amp. so getting parts not should be easy enough.

[paulypbass]

well my repair man got back to me earyler and said iv blown 8 output transitors. but the good thing is KORG stock them and there only 1.58 each. hes gunna make sure nothing else in the amp is broken though. hes also gunna put a new pre amp tube in it for me. so not that bad after all.

[icastle]

[quote name='paulypbass' timestamp='1334275519' post='1613838']
well my repair man got back to me earyler and said iv blown 8 output transitors. but the good thing is KORG stock them and there only 1.58 each. hes gunna make sure nothing else in the amp is broken though. hes also gunna put a new pre amp tube in it for me. so not that bad after all.
[/quote]

That is good news - especially the £1.58 each.

[bertbass]

Not too bad then. You've learned the lesson I learned a long time ago, switch the amp off before plugging the speakers in. Even if it's supposed to be alright because the amp is protected, I never trust it and prefer to be on the safe side.