You will have to work yourself trough every step in the learning procedure but, determined as you are, I’m sure you’ll make it.
As said before, I have good hope your front end is working (Q1, Q2, Q3).
Now, switch off the amplifier, discharge the big capacitors with a resistor from say 10 to 20 ohm / 5 watt. Make sure there is only a very small voltage left over the capacitors. If possible, disconnect them from the circuit. If some voltage is left in the circuit during measuring, your ohmic values will not be correct, you have the risk of damaging the meter and the amp.
Measure every component starting with the big mosfets, then the two transistors Q4 and Q5. You could leave Q4 out of the circuit if you like, it’s only there for overcurrent protection.
Then comes every resistor, if you don’t measure more or less exact values, lift one leg out of the circuit.
Check every wire twice, every solder connection. Confirm with an ohm meter that the connection really exists. Confirm with the schematic that all connections are correct. Work slowly and persistent. Take a break now and then. Don’t assume the amp will work with even one broken component, one wrong or bad connection.
Good luck.
/Hugo 🙂
As said before, I have good hope your front end is working (Q1, Q2, Q3).
Now, switch off the amplifier, discharge the big capacitors with a resistor from say 10 to 20 ohm / 5 watt. Make sure there is only a very small voltage left over the capacitors. If possible, disconnect them from the circuit. If some voltage is left in the circuit during measuring, your ohmic values will not be correct, you have the risk of damaging the meter and the amp.
Measure every component starting with the big mosfets, then the two transistors Q4 and Q5. You could leave Q4 out of the circuit if you like, it’s only there for overcurrent protection.
Then comes every resistor, if you don’t measure more or less exact values, lift one leg out of the circuit.
Check every wire twice, every solder connection. Confirm with an ohm meter that the connection really exists. Confirm with the schematic that all connections are correct. Work slowly and persistent. Take a break now and then. Don’t assume the amp will work with even one broken component, one wrong or bad connection.
Good luck.
/Hugo 🙂
Thanks Hugo!🙂 I will take it easy. Is it possible that the wire on Kristians boards, J1, is the problem? I will check it out just like you told. Goodnight. Teake.
The tracks on the PCB are not visible so I have no idea what's the purpose of J1.
Since it's there, I assume there should be a bridge just like at J2 position.
/Hugo 🙂
Since it's there, I assume there should be a bridge just like at J2 position.
/Hugo 🙂
he Hugo!
I stopped fot a while to take a claer mind and will start over again in a few days, I have to take my time for it because I can't work in a hurry, but last time I could not get any further, so I feel a little helpless, but the hope is still there. Thanks again buddy for having your interest in my monsterprocess. greetings teake
I stopped fot a while to take a claer mind and will start over again in a few days, I have to take my time for it because I can't work in a hurry, but last time I could not get any further, so I feel a little helpless, but the hope is still there. Thanks again buddy for having your interest in my monsterprocess. greetings teake
Is it working already ?, if you have a question, i can help you by phone (in dutch). Words are faster than mail.
He Berry!
Thanks for the help. My phonenumber is 0512-840224 and whats yours? So I will call you when I'll start again. greetings Teake.
Thanks for the help. My phonenumber is 0512-840224 and whats yours? So I will call you when I'll start again. greetings Teake.
Oke I.am sorry i will smash myself on the head. teake.I will call you tomorrow, (We Dutch people just simple take a new phone number when there is a stalker !!#@#$@#$#@%^)
one channel working
Hi there!
I am a happy guy, I went to a friend who is an electrician, he has a scope and other things , so he helped me with my aleph 5.
Now one channel is working. hiep hoi. The mpsa 18, Q5 was broken, and surprise there was a nice sinus. Now we will take a look to the other channel over a few days. And I will mail.
So Berry thanks for the interest and the others too.
Greetings Teake.
Hi there!
I am a happy guy, I went to a friend who is an electrician, he has a scope and other things , so he helped me with my aleph 5.
Now one channel is working. hiep hoi. The mpsa 18, Q5 was broken, and surprise there was a nice sinus. Now we will take a look to the other channel over a few days. And I will mail.
So Berry thanks for the interest and the others too.
Greetings Teake.
mpsa 18 VS BC550
hi there!
The channel I got right I us mpsa 18, is it possible to do bc550 on the other channel instead off mpsa 18 without problems?
Thanks Teake.
hi there!
The channel I got right I us mpsa 18, is it possible to do bc550 on the other channel instead off mpsa 18 without problems?
Thanks Teake.
Hi Teake,
Another possibility; buy four BC550. They are not that expensive. First get the other channel working, then change the first channel to an BC 550. When you go all the way with a double mono power supply make sure all parameters are the same further on in the energy path. The other two are reserve!
Please remember the pin layout on the BC550 is different!
Almost there!
Harry
Another possibility; buy four BC550. They are not that expensive. First get the other channel working, then change the first channel to an BC 550. When you go all the way with a double mono power supply make sure all parameters are the same further on in the energy path. The other two are reserve!
Please remember the pin layout on the BC550 is different!
Almost there!
Harry
Hi there!
I got me some Motorola MPSA 18, are they the same as the fairchilds? And we did put 3 new irf 9610 on the pcb and 6 new
mosfets. But stil it did not work. Q5 doesn't give any value and the mosfets again broke down. When we measured Q5 afterwards and the 221K they were good.
We only got connected now onbalanced output, that is, we did not connect the + anywhere, we removed it, the minus was connected with a short wire to ground on the pcb and the ground we did not connected to the unbalanced output instead we turned it round the U cable without connection. The U cable went to unbalanced output/input. We made a ground connection from the unbalanced output to the ground on the powersupply.
Did we do something wrong?
When we made the other channel and when it was running the powersupply gave 31,6 volt, before it gave 35,4 volt. The channel wich is not working gives still 35,4 volt. The IRF 9610 gave 3,8 volt, z5 gave 9,1 volt and r14 gave 4,9 volt. Wrong connections. We wil take some measuremens without the mosfets connected.
Greetings teake.
I got me some Motorola MPSA 18, are they the same as the fairchilds? And we did put 3 new irf 9610 on the pcb and 6 new
mosfets. But stil it did not work. Q5 doesn't give any value and the mosfets again broke down. When we measured Q5 afterwards and the 221K they were good.
We only got connected now onbalanced output, that is, we did not connect the + anywhere, we removed it, the minus was connected with a short wire to ground on the pcb and the ground we did not connected to the unbalanced output instead we turned it round the U cable without connection. The U cable went to unbalanced output/input. We made a ground connection from the unbalanced output to the ground on the powersupply.
Did we do something wrong?
When we made the other channel and when it was running the powersupply gave 31,6 volt, before it gave 35,4 volt. The channel wich is not working gives still 35,4 volt. The IRF 9610 gave 3,8 volt, z5 gave 9,1 volt and r14 gave 4,9 volt. Wrong connections. We wil take some measuremens without the mosfets connected.
Greetings teake.
He Berry I got 2 monoamplifiers in one case, only connected together on floating earth. greetings Teake.
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