Got the avondale bridge now, however, i must ask further questions before i install this. putting in the big capp blew the fuse, should i have put some snubber caps in before the big caps to reduce the load draw, or will a soft start module fitted at the mains end be a better install. i have put the old caps back in and checked everyting. so any advice welcome before i install new bridge and blow it up!
Tc
Tc
update: blows 2 and 2.5 td fuses. the latter fuse does blow less faster. checked all values and while res values are good voltage is tiwce higher in one side than the other.
JonH what to do mean by seconday and disconnecting rest of amp?
sorry for late reply as i have been awaiting fuses.
thanks
Tc
JonH what to do mean by seconday and disconnecting rest of amp?
sorry for late reply as i have been awaiting fuses.
thanks
Tc
>checked all values and while res values are good voltage is tiwce higher in one side than the other.
Voltage is twice as higher on one side than the other of WHAT exactly ?
A transformer has two sides, the primary (input) side and the secondary (output) side.
The fuse is blowing because the current flowing through it exceeds its rating for a sufficient time for the fuse wire to melt.
The supply for the output stage of the amplifier consists of a transformer, a bridge rectifier and a some capacitors. As I understand it you have increased the capacitance from the original design. The capacitors will draw a lot of current when they first charge up (the inrush current). Also if one of the output transistors has failed short circuit this too will allow a large current to flow. Either of these will blow the fuse. I was suggesting you isolate the supply from the output stage to discount this part of the amplifier. Perhaps though it would be much simpler if you just measure the resistance between the positive supply and ground and the negative supply and ground (with the amp off of course) this should be a high reading, if it is less than a few ohms then you have a short somewhere and this is why the fuse keeps blowing. Make some measurements and report back.
Voltage is twice as higher on one side than the other of WHAT exactly ?
A transformer has two sides, the primary (input) side and the secondary (output) side.
The fuse is blowing because the current flowing through it exceeds its rating for a sufficient time for the fuse wire to melt.
The supply for the output stage of the amplifier consists of a transformer, a bridge rectifier and a some capacitors. As I understand it you have increased the capacitance from the original design. The capacitors will draw a lot of current when they first charge up (the inrush current). Also if one of the output transistors has failed short circuit this too will allow a large current to flow. Either of these will blow the fuse. I was suggesting you isolate the supply from the output stage to discount this part of the amplifier. Perhaps though it would be much simpler if you just measure the resistance between the positive supply and ground and the negative supply and ground (with the amp off of course) this should be a high reading, if it is less than a few ohms then you have a short somewhere and this is why the fuse keeps blowing. Make some measurements and report back.
Any luck yet, TC?
If it continues to look grim, let me know if you fancy splitting the cost of getting a second amp off eBay for spares.
I've been on the lookout for a second transformer for quite some time but can't justify shipping an entire working amp to Canada just to cannibalize it. If it comes to it then it would be cool if I could chip in some cash for a sacrificial amp to get shipped to you and then you could forward just the transformer to me.
Let me know,
Ben
If it continues to look grim, let me know if you fancy splitting the cost of getting a second amp off eBay for spares.
I've been on the lookout for a second transformer for quite some time but can't justify shipping an entire working amp to Canada just to cannibalize it. If it comes to it then it would be cool if I could chip in some cash for a sacrificial amp to get shipped to you and then you could forward just the transformer to me.
Let me know,
Ben
Besides toroid and remote, is anyone currently in need of anything if I have to resort to parting out a working amp? I'm looking for someone to receive shipping and forward me just the parts I need. I'd ideally like to avoid a perfectly good chassis ending up in a landfill, but it'd be more than it's worth to ship it whole.
