I recently finished both of my F5 Turbo monoblocks other than installing the power switches, which hadn't arrived yet. They were working, i.e., playing music, and I had them biased close to where I wanted them.
The power switch I am using has a LED unit that that is 12V AC or DC, so I decided to use the 12V secondaries from my transformer, which I was not using for anything else.
The issue I had is that the Antek schematic for my transformer appears to have been wrong, because the two orange wires that were supposed to be 12 V, were different secondaries. My transformer has 12V and 18V secondaries, and the schematic said the two orange wires were the 12 V, but it turns out one orange and one brown were 12V and the other orange and the other brown were 18B. No idea why.
Anyway, I mis-wired the switch and after powering up the amp, all sorts of weird **** happened in the few seconds before I powered it down. There was definitely a sound and burning smell of some sort, which I can't find on any of the boards, but I assume was the LED unit burning out.
So I disconnected the switch altogether and started up with a dim bulb tester, and the was initially pleased because the bulb dimmed. But then I noticed that the LEDs on the power supply board were doing something odd. Previously, when I powered down, they would both stay on for a fairly long time. Following this event, one (on the negative side) would fade out pretty quickly.
So I disconnected the other PCBs from the power supply board, fired it up, and it seemed to work fine. Both PCBs stay lit, the voltage is constant at 41/-41 on each side, and I see no issue.
Plugged the PCBs back in and same issue. So I'm assume there is a short or some issue somewhere. I started with the main board and checked the two transistors and the Jfets, and all were fine. Before I disassemble anything else, I wanted to get some advice on how to potentially find the problem without just going part by part.
Not an engineer by training, so please excuse my stupidity. I guess it's good that I love this hobby even when **** like this happens.
Thanks in advance.
The power switch I am using has a LED unit that that is 12V AC or DC, so I decided to use the 12V secondaries from my transformer, which I was not using for anything else.
The issue I had is that the Antek schematic for my transformer appears to have been wrong, because the two orange wires that were supposed to be 12 V, were different secondaries. My transformer has 12V and 18V secondaries, and the schematic said the two orange wires were the 12 V, but it turns out one orange and one brown were 12V and the other orange and the other brown were 18B. No idea why.
Anyway, I mis-wired the switch and after powering up the amp, all sorts of weird **** happened in the few seconds before I powered it down. There was definitely a sound and burning smell of some sort, which I can't find on any of the boards, but I assume was the LED unit burning out.
So I disconnected the switch altogether and started up with a dim bulb tester, and the was initially pleased because the bulb dimmed. But then I noticed that the LEDs on the power supply board were doing something odd. Previously, when I powered down, they would both stay on for a fairly long time. Following this event, one (on the negative side) would fade out pretty quickly.
So I disconnected the other PCBs from the power supply board, fired it up, and it seemed to work fine. Both PCBs stay lit, the voltage is constant at 41/-41 on each side, and I see no issue.
Plugged the PCBs back in and same issue. So I'm assume there is a short or some issue somewhere. I started with the main board and checked the two transistors and the Jfets, and all were fine. Before I disassemble anything else, I wanted to get some advice on how to potentially find the problem without just going part by part.
Not an engineer by training, so please excuse my stupidity. I guess it's good that I love this hobby even when **** like this happens.
Thanks in advance.
first is buzzer check for shorts, each and every semiconductor
if any is suspicious in situ (compare same positions between channels) you must pull it and measure it alone
if any is suspicious in situ (compare same positions between channels) you must pull it and measure it alone
Can I start up the amp with a dim bulb tester without the n-channel and p-channel boards installed to test the front end board?
Likewise, can I start up the amp with a dim bulb tester without either the n-channel or p-channel boards attached to try to figure out which channel is the problem?
Likewise, can I start up the amp with a dim bulb tester without either the n-channel or p-channel boards attached to try to figure out which channel is the problem?