rocker 30 fuses, chassis removing and killing myself

[tacky]

Hello. Anyone knows, what is the size of Rocker 30 T2A and T0,5A fuses? 5x20 or 6x32 or the Mains and HT fuses aren't the same size? (I'm buying them only for backup, if any of them blows out) Oh and another dumb question - how to remove the chassis (it's a head), do I unscrew it from the bottom (from the rubber feet?) and don't touch the backside at all? And when changing power and preamp tubes, without touching anything under the chassis, is there any other way I could accidentally get shocked? (Sorry for the stupid questions, but I'm doing this for the first time in my life)

[Jondog]

5x20mm fuses I believe. When changing your tubes, first don't do it when they are hot, you'll burn yourself or if you have to use protective covering on your hand, I use one of those small silicone oven mitt things. Make sure your amp is powered off and gently pull them out of the sockets, may require slight wiggling, not too much. Theres no reason for you to have to remove the chassis to change tubes, just the orange grate on the back and you should have enough room to work. If you must remove the chassis, yes the four rubber feet are what is holding it in. I find it easy to unscrew them and pull the chassis out the front by the chrome handles. Don't touch anything inside the amp as it is possible for there to be high voltages still in the capacitors. But again, there is nothing inside the amp you need to mess with. There are fuses in there for the heater supplies, but as long as your tubes are heating up, there is no reason to have to check them. My best advice if you are going to pull the chasis out, is to do it after you've been using the amp and the tubes are hot, I've found that on my Rocker, the hot tubes will actually drain the voltages from the caps. But, this is in no way a for sure safe method, as you never know unless you check for the voltage with proper equipment.

[tacky]

all right, thanks Jondog. will try to do it without removing the chassis, putting in new preamp tubes might be a bit tricky, since I probably won't see the pin order, but nothing too hard i guess

[Jondog]

The power tubes have an index spline on them so they won't go in unless it's lined up. The preamp tubes have a space and won't go in unless they're all lined up. They should plug in firmly without excess force. As use pull the old tubes out pay attention to where the space is as you pull them out for better reference.

[jerem37]

Hello,

that's a very good question for the fuse...
Since i had an issue with a Vox AC4, i decide to buy some fuse to have in spare.
I have a Rocker30 head, that runs in 220-240V (France), and i'd like to know all the references of the different fuses used in it.
So, there is the 5*20mm T500mAL /250V
I think there is a 6,3A/250V (T? Low Breazking Cap? 5*20mm?) for filament heating
I found some forums talking about another ones: 3,15A and/or 2A...
Maybe an Orange tech can give us the complete and detailed list of the fuse in the R30?
If we don't find on Orange amps forum, we'll never...
Thanks.

[fiveightandten]

My best advice if you are going to pull the chasis out, is to do it after you've been using the amp and the tubes are hot, I've found that on my Rocker, the hot tubes will actually drain the voltages from the caps. But, this is in no way a for sure safe method, as you never know unless you check for the voltage with proper equipment.

I'm a little late to the game, but I disagree with this method. Removing the chassis right after the amp has been powered off is just about the most dangerous thing you can do.

Leave the amp off and unplugged for a few hours with the standby switch in the ON position. It's almost certain that all the voltage will bleed off. Pulling a chassis with live voltage and hot tubes is dangerous. I've built entire amps from scratch, I worked as a repair tech for a local music store for a while, and I don't even do that.

You are correct in saying that the only way to know whether or not there is still voltage present is to check with a meter.

Be safe guys.

-Nick

[a.hun]

Be safe guys.

A huge +1 on that...

Listen, some amps will self discharge their big capacitors, especially if powered down while leaving a standby switch set to 'play'.

BUT...

It depends on the amp and the individual circuits. Some will, some won't. (And even with those that do certain failures could 'potentially' prevent self discharge.) Smart techs simply won't trust the internals of a valve amp without discharging the caps themselves and then checking internal voltages to be 110% sure.

http://www.thegearpage.net/board/showth ... =discharge" onclick="window.open(this.href);return false;


Andy.

[fiveightandten]

Be safe guys.

A huge +1 on that...

Listen, some amps will self discharge their big capacitors, especially if powered down while leaving a standby switch set to 'play'.

BUT...

It depends on the amp and the individual circuits. Some will, some won't. (And even with those that do certain failures could 'potentially' prevent self discharge.) Smart techs simply won't trust the internals of a valve amp without discharging the caps themselves and then checking internal voltages to be 110% sure.

http://www.thegearpage.net/board/showth ... =discharge" onclick="window.open(this.href);return false;


Andy.

Some good posts in that link...just ignore the people discharging caps with a screwdriver. We've all done it...but it's dangerous.

I'm sure i've mentioned this before, but years ago I had my old OR-80 discharge into my hand right after I turned the amp off. I had the chassis out and upside down, as I was biasing it. My hand slipped while I was connecting a lead to discharge the caps and bumped right into one of the prongs on the standby switch (something I added).

You only have to feel 500VDC go through you once. After that, believe me, you're quite mindful of where your hands are in an amp that hasn't been bled. I'd prefer most people not have to experience that to respect the danger involved.

-Nick

[Jondog]

As for the killing yourself part, don't do it! You have many days of rocking ahead of you!