I just got my new transformer. It's another Antek AS-4218. Yes it does say AS-4218 on the actual unit.
Unplugged from anything except the mains each secondary pair makes 25volts AC.
When plugged into the two bridge rectifiers I get 22voltsDC on each pair.
Plugged into the power supply I get 33volts DC from V+ to ground, 33volts DC from ground to V- and 66voltsDC between V+ and V-.
Is this how it should be or is it way too high?
If too high does it indicate that the caps are damaged?
Thanks.
Unplugged from anything except the mains each secondary pair makes 25volts AC.
When plugged into the two bridge rectifiers I get 22voltsDC on each pair.
Plugged into the power supply I get 33volts DC from V+ to ground, 33volts DC from ground to V- and 66voltsDC between V+ and V-.
Is this how it should be or is it way too high?
If too high does it indicate that the caps are damaged?
Thanks.
According to the specs at http://www.antekinc.com/content/AS-4218.pdf
the two secondaries should deliver 18Volts AC, NOT 25Volts AC.
Did you connect the middle black and red wires together for 230-240Volts AC on the primaries? Did you put your DMM on AC if it is not autoranging?
I just measured again. It's only measuring 31 volts each side and it's the same each side of the power supply.
Sorry Albert, what is CRC? I assume it means the PCB ?
Lorado, yes I connected the middle black to the middle red and the first test showed 25V AC coming out of each of the secondary pairs. I was surprised as I expected a little higher than 18V AC but not that much.
Is my DMM OK ? Maybe I had better get another one to verify.
But I won't be connecting the amp circuits till I'm sure or someone assures me that the amount is OK.
Sorry Albert, what is CRC? I assume it means the PCB ?
Lorado, yes I connected the middle black to the middle red and the first test showed 25V AC coming out of each of the secondary pairs. I was surprised as I expected a little higher than 18V AC but not that much.
Is my DMM OK ? Maybe I had better get another one to verify.
But I won't be connecting the amp circuits till I'm sure or someone assures me that the amount is OK.
OK I just measured my mains voltage. It's showing 313V AC. This would explain it.
Now the only explanation I have for this would be that I have a large bank of solar panels on the roof and it's just possible that the installers have done something wrong in the power box. Either that or my DMM is truly bad. I will investigate and report back.
Now the only explanation I have for this would be that I have a large bank of solar panels on the roof and it's just possible that the installers have done something wrong in the power box. Either that or my DMM is truly bad. I will investigate and report back.
Check some batteries on the dc scale of the DMM. Chances are the DMM is faulty and may read high on DC ranges as well. I would think that with 313vac coming into the house you would have other issues with appliances and light bulbs etc because that is way higher than the usual tolerances. It’s always good to have a second meter available to verify readings. Typically, during the running up of a diy amplifier it is also very convenient to have 2 meters to measure DC output offset and bias current.
Since I use meters daily in my work and hobbies I favour the Fluke brand which are pricey but have proven reliable and long lived. There are lots of generic brands out there that offer good performance and excellent value as long as you have a second meter for backup and verification.
Since I use meters daily in my work and hobbies I favour the Fluke brand which are pricey but have proven reliable and long lived. There are lots of generic brands out there that offer good performance and excellent value as long as you have a second meter for backup and verification.
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I had a wonky DMM that would slowly drop voltage readings the longer it stayed on. Needless to say it drove me crazy when I was setting the bias on the Aleph J since I thought it was something wrong with the amp. I had the bias turned all the way up and just couldn't figure out why that side was so hot but biasing so low.
Luckily I had a second meter on the other channel - brand new with fresh batteries - on hand to check against!
Luckily I had a second meter on the other channel - brand new with fresh batteries - on hand to check against!
Hi guys,
I just got home from my friend's place , he's an electrician, so we compared meters. His read 250 v ac when mine read 280.
I have dug out my old meter.
It reads 250 V AC from the mains so now I can trust it.
So from the secondary transformer outputs I get 19.9V AC.
Right then plugged into the bridge recs I get 26V DC and the same at either end of the power supply.
Should I now try to plug in one side of my amp boards?
I just got home from my friend's place , he's an electrician, so we compared meters. His read 250 v ac when mine read 280.
I have dug out my old meter.
It reads 250 V AC from the mains so now I can trust it.
So from the secondary transformer outputs I get 19.9V AC.
Right then plugged into the bridge recs I get 26V DC and the same at either end of the power supply.
Should I now try to plug in one side of my amp boards?