Yup-it's broke! Sorry. Not wanting to be an a-hole but there are MANY things that can cause an instant blow from a bad switch to shorted tube to cap shorted to transformer bad to ............. Sorry but you get the idea. There are a crapload of things that could do it. Even just a simple short. You need to isolate where in the system the drain is being caused and go from there. We will give you any help we can but you need a little more info to go from here. Do you have any electronics training or knowledge? It DOES make it a little easier. Just wanting to help. Mike.
no I know the basics check tubes and bias.I don't have a lot of tools other than a bias probe a multi tester and a Orange tube tester.The amp was fine for a couple band practices then the last time we went to play on it ; it just blew the fuse every time it was switched out of standby I tried about three times and it blew the fuse every time.I'm just trying the easy stuff first I haven't taken the chassis out yet probably Friday I'm keeping my fingers crossed that it's not something major like a transformer. Their is a top notch amp tech around here but he is so backed up it will probably take a couple months
First thing is you need to stop wasting fuses/ Can you safely build a lamp tester? Look at the pic I sent. Build that and then we can go farther. Also, have you just tried to take it off standbye with the power tubes out? When you have the lamp tester with a 100 watt bulb, a normal amp will light the lamp brightly for second, then dim out to a dull low glow. Lamp on full bright all the time and you have a short/draw somewher/ Mike.
I'm having the same problem. Used the limiter. Doing what you explained. No tubes installed. I bench tested the power transformer (it was out of the amp when I got it)
Green leads have 6 volts/4.5
Red have 217/170
Orange have 20/15
High and low voltage tested.
Re installed the transformer.
Same thing happening. It was only when I removed the orange leads that it stopped blowing the fuse. The electrolytics were changed before I got the amp and they look fine.
Orange leads power the bias supply AND the filaments for the tubes so either you have a crap tube heater that's shorted or the bias supply is going to ground somewhere (over the rainbow!!!!). Bias cap???? Check the caps on the bias supply board and MAYBE check the current draw on the heater circuit. Mike.
Yup-it's broke! Sorry. Not
Yup-it's broke! Sorry. Not wanting to be an a-hole but there are MANY things that can cause an instant blow from a bad switch to shorted tube to cap shorted to transformer bad to ............. Sorry but you get the idea. There are a crapload of things that could do it. Even just a simple short. You need to isolate where in the system the drain is being caused and go from there. We will give you any help we can but you need a little more info to go from here. Do you have any electronics training or knowledge? It DOES make it a little easier. Just wanting to help. Mike.
blowing fuses
no I know the basics check tubes and bias.I don't have a lot of tools other than a bias probe a multi tester and a Orange tube tester.The amp was fine for a couple band practices then the last time we went to play on it ; it just blew the fuse every time it was switched out of standby I tried about three times and it blew the fuse every time.I'm just trying the easy stuff first I haven't taken the chassis out yet probably Friday I'm keeping my fingers crossed that it's not something major like a transformer. Their is a top notch amp tech around here but he is so backed up it will probably take a couple months
First thing is you need to
First thing is you need to stop wasting fuses/ Can you safely build a lamp tester? Look at the pic I sent. Build that and then we can go farther. Also, have you just tried to take it off standbye with the power tubes out? When you have the lamp tester with a 100 watt bulb, a normal amp will light the lamp brightly for second, then dim out to a dull low glow. Lamp on full bright all the time and you have a short/draw somewher/ Mike.
HD 130 blowing fuses
OK I think I have the stuff to build that give me a day or two to build it and I will get back with you. Thank you very much
HD 130 blowing fuses
Did you figure out the cause of the blowing fuses?
Hd130 blowing fuse
I'm having the same problem. Used the limiter. Doing what you explained. No tubes installed. I bench tested the power transformer (it was out of the amp when I got it)
Green leads have 6 volts/4.5
Red have 217/170
Orange have 20/15
High and low voltage tested.
Re installed the transformer.
Same thing happening. It was only when I removed the orange leads that it stopped blowing the fuse. The electrolytics were changed before I got the amp and they look fine.
Orange leads power the bias
Orange leads power the bias supply AND the filaments for the tubes so either you have a crap tube heater that's shorted or the bias supply is going to ground somewhere (over the rainbow!!!!). Bias cap???? Check the caps on the bias supply board and MAYBE check the current draw on the heater circuit. Mike.
Hd130 power transformer
I found that while in the circuit, both orange leads were going to ground. Removed Secondary leads from amp. Orange and red show continuity. Not good.
No, in this case, orange
No, in this case, orange and red don't mix. Sounds like the tranny's toast.