My beloved Alpha 8 has survived a trans-atlantic voyage only to refuse to accept a 110v input.
I have swapped the fuses on the Alpha 8 and its power amp. The power amp is fine but the Alpha 8 is dead. I checked all the fuses and its definitely getting power, I even switched it back to the 240v fuse to try that and it powers up, but obviously wont play.
I would really love to be able to fix this. And it seems like from what I have read on this forum someone here might know a solution. I am up for re-soldering if required.
Thanks for any help.
Simon
I have swapped the fuses on the Alpha 8 and its power amp. The power amp is fine but the Alpha 8 is dead. I checked all the fuses and its definitely getting power, I even switched it back to the 240v fuse to try that and it powers up, but obviously wont play.
I would really love to be able to fix this. And it seems like from what I have read on this forum someone here might know a solution. I am up for re-soldering if required.
Thanks for any help.
Simon
Let's clarify - You have a 240V amplifier and you are attempting to power it with just 110V?
Is there a voltage supply changeover switch to allow this - or perhaps you have a dual winding transformer that you have already rewired to suit a 110V supply?
Otherwise, you can take product warnings and advice as real and that they do apply to the products on which they are placed. Only switchmode powered appliances are useable across a range of mains voltages and then only if marked accordingly.
Fuses have little to do with this other than that they must be doubled in current rating when you halve the supply voltage. Ohm's law does actually have application to amplifiers! This is something a convertible appliance will have documentation and marking to cover in any case.
If I were you, I wouldn't even attempt to use a UK lightbulb nor continue to try to use 110V power on your amplifier unless you know what needs doing. You will need to obtain a step-up transformer, rated at least for the total current rating of all the equipment.
Is there a voltage supply changeover switch to allow this - or perhaps you have a dual winding transformer that you have already rewired to suit a 110V supply?
Otherwise, you can take product warnings and advice as real and that they do apply to the products on which they are placed. Only switchmode powered appliances are useable across a range of mains voltages and then only if marked accordingly.
Fuses have little to do with this other than that they must be doubled in current rating when you halve the supply voltage. Ohm's law does actually have application to amplifiers! This is something a convertible appliance will have documentation and marking to cover in any case.
If I were you, I wouldn't even attempt to use a UK lightbulb nor continue to try to use 110V power on your amplifier unless you know what needs doing. You will need to obtain a step-up transformer, rated at least for the total current rating of all the equipment.
Ian,
Thanks for the reply. To clarify,
The amplifier in question allows 115v or 240v supply. The change over is accomplished by swapping a fuse on the circuit board to a different position on the circuit board.
From what you have said this would appear to be a dual winding transformer. The problem seems to be that the 115v 'wind' is dead! I would like to know what would be a sensible fault finding procedure to get this lovely amp running on 115v.
Thanks again.
Simon
Thanks for the reply. To clarify,
The amplifier in question allows 115v or 240v supply. The change over is accomplished by swapping a fuse on the circuit board to a different position on the circuit board.
An externally hosted image should be here but it was not working when we last tested it.
From what you have said this would appear to be a dual winding transformer. The problem seems to be that the 115v 'wind' is dead! I would like to know what would be a sensible fault finding procedure to get this lovely amp running on 115v.
Thanks again.
Simon
There is a 403 permissions error with posting that pic, unfortunately. It would help.
To get the dual voltage primary to change over, it's necessary to make 2 winding connection changeovers, unless one winding at least can carry full 115V supply current - then the switching is only a single wire swap between one or both windings in series. It should be simple enough to trace back on what change(s) you actually made and whether it is adequate. Actually, it wouldn't work on 240V unless both windings were fully functional. That shouldn't be the issue.
Unfortunately, to test what is or isn't working, you will need at least a cat.II approved DMM (for safety) and then to test what AC and DC you have at the output of the power supply. Then you know for certain what problems there are, if any.
To get the dual voltage primary to change over, it's necessary to make 2 winding connection changeovers, unless one winding at least can carry full 115V supply current - then the switching is only a single wire swap between one or both windings in series. It should be simple enough to trace back on what change(s) you actually made and whether it is adequate. Actually, it wouldn't work on 240V unless both windings were fully functional. That shouldn't be the issue.
Unfortunately, to test what is or isn't working, you will need at least a cat.II approved DMM (for safety) and then to test what AC and DC you have at the output of the power supply. Then you know for certain what problems there are, if any.
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Try attaching your picture directly to the forum,
"To add a photo, files or non standard files.
First click "go advanced" in the box below the "quick reply" message box. Doesn't matter if you decide half way through a message to do that, it carries it foward.
Then click "Manage attachements". Maximise the new Window so that you can see all the text.
Click browse in the first box at the top and find your picture. Repeat for any more pictures.
Click upload... a message appears "uploading"
When complete the files will show as being attached. Now click the small text that says "close this window"
The pictures should now be attached and when you submit your post they will appear.
Make sure your pics aren't too big, a couple of 100k is plenty, and many members object when they are massive and it alters the margins
It tells you in the attachments window what max sizes are allowed.
If you want to attach a file that has a non standard format for example excel, circuit simulation etc then try putting the files in a zipped folder and attaching that."
"To add a photo, files or non standard files.
First click "go advanced" in the box below the "quick reply" message box. Doesn't matter if you decide half way through a message to do that, it carries it foward.
Then click "Manage attachements". Maximise the new Window so that you can see all the text.
Click browse in the first box at the top and find your picture. Repeat for any more pictures.
Click upload... a message appears "uploading"
When complete the files will show as being attached. Now click the small text that says "close this window"
The pictures should now be attached and when you submit your post they will appear.
Make sure your pics aren't too big, a couple of 100k is plenty, and many members object when they are massive and it alters the margins
It tells you in the attachments window what max sizes are allowed.
If you want to attach a file that has a non standard format for example excel, circuit simulation etc then try putting the files in a zipped folder and attaching that."
Mooley: Thanks I appreciate the help with the pictures.
Ian: I appreciate you explaining that to me, I know understand how a dual winding transformer works, I have reposted the pics for you to look at.
Jayceee: After your comment I had a good look at my other amp (same Alpha 8 but the power amp for the first) and it does appear there is a wire missing from the power supply side but I definitely havent removed anything and have owned it from new.
Picture of problem amp:
Difference between fuse areas on problem amp and its functioning power amp (it has a different connection but the first appears to be missing a grey wire in the middle of the connectors):
Any ideas? Thanks.
Ian: I appreciate you explaining that to me, I know understand how a dual winding transformer works, I have reposted the pics for you to look at.
Jayceee: After your comment I had a good look at my other amp (same Alpha 8 but the power amp for the first) and it does appear there is a wire missing from the power supply side but I definitely havent removed anything and have owned it from new.
Picture of problem amp:
Difference between fuse areas on problem amp and its functioning power amp (it has a different connection but the first appears to be missing a grey wire in the middle of the connectors):
Any ideas? Thanks.
I'm afraid just going off the colours doesn't mean anything to me (but it might to someone else).
I'd have to look at all the primary connections and possibly first measuring the DC resistance of the primary with it set for 240 volts as a guide. Then I'd look and see what the connection options might be. If the tranny really does accept 110 and 240v then is it two separate windings in series ? or is it one winding with tappings ?
If I was still unsure I'd disconnect the secondaries for safety of the unit and then fit a bulb tester in series with the mains and have a try with different connection options to give the required secondary voltage. The bulb tester keeps it all safe.
It's one of those things you either know for sure or else have to have it in front of you
I'd have to look at all the primary connections and possibly first measuring the DC resistance of the primary with it set for 240 volts as a guide. Then I'd look and see what the connection options might be. If the tranny really does accept 110 and 240v then is it two separate windings in series ? or is it one winding with tappings ?
If I was still unsure I'd disconnect the secondaries for safety of the unit and then fit a bulb tester in series with the mains and have a try with different connection options to give the required secondary voltage. The bulb tester keeps it all safe.
It's one of those things you either know for sure or else have to have it in front of you
Most of the Alpha's were fairly similar.
If the Alpha 8 is the same as the Alpha 9 (in the PSU part anyway), then simply removing the 115V fuse and inserting the 240V fuse changes the voltage.
If this doesn't work you are going to have to investigate the transformer.
A phone call to Matt at Arcam +44 1223 203200 with your Serial Number, he will verify that you have a dual voltage transformer.
If the Alpha 8 is the same as the Alpha 9 (in the PSU part anyway), then simply removing the 115V fuse and inserting the 240V fuse changes the voltage.
If this doesn't work you are going to have to investigate the transformer.
A phone call to Matt at Arcam +44 1223 203200 with your Serial Number, he will verify that you have a dual voltage transformer.
Attachments
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NO, Arcam use a single winding on the Alpha 8,9,10. If you look at the post above you will see how they achieve this.
There are several DIY approaches to converting the unit to 110V.
The Arcam 8 is about 55W/Channel so it needs a supply of about 200VA - 300VA would be better.
You can either use a step-up transformer and power it with 240V.
OR.
Replace the transformer. It's unlikely that you would be able to buy the dual output transformer from your local stockist, so there are three options.
1. Custom Built - Expensive but not horrendously so.
2. Dual Transformer - Fit two transformers, one for the main HT-0-HT supply and the second for the LT supply.
3. DIY - Buy a 300VA transformer to provide HT-0-HT and add the supplementary windings for LT yourself.
I've said 300VA as that is what I would use in a DIY amplifier, if the Alpha has a 160VA transformer then obviously that will suffice.
The Arcam 8 is about 55W/Channel so it needs a supply of about 200VA - 300VA would be better.
You can either use a step-up transformer and power it with 240V.
OR.
Replace the transformer. It's unlikely that you would be able to buy the dual output transformer from your local stockist, so there are three options.
1. Custom Built - Expensive but not horrendously so.
2. Dual Transformer - Fit two transformers, one for the main HT-0-HT supply and the second for the LT supply.
3. DIY - Buy a 300VA transformer to provide HT-0-HT and add the supplementary windings for LT yourself.
I've said 300VA as that is what I would use in a DIY amplifier, if the Alpha has a 160VA transformer then obviously that will suffice.
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Yep, looks like Arcam started skipping the dual tapped primary winding, so it is 230V only.
The original transformer is a 160VA unit with 28-0-28 vac secondaries for the main supply, and a 0-9 vac secondary for powering the microcontroller. If this 9v is missing, then the remote controlled volume simply wont work - but that is all.
You should be able to get an off the shelf 2x25VAC transformer and fit this, the small loss in voltage will not matter. If you absolutely need the remote volume, you can always fit a small (6VA should be plenty) 9V transformer to power the micro.
Alternatively if you have an 8P power amp, and it has the extra 9v winding (unused), put that transformer into the integrated amp, and fit the replacement transformer to the 8P.
The original transformer is a 160VA unit with 28-0-28 vac secondaries for the main supply, and a 0-9 vac secondary for powering the microcontroller. If this 9v is missing, then the remote controlled volume simply wont work - but that is all.
You should be able to get an off the shelf 2x25VAC transformer and fit this, the small loss in voltage will not matter. If you absolutely need the remote volume, you can always fit a small (6VA should be plenty) 9V transformer to power the micro.
Alternatively if you have an 8P power amp, and it has the extra 9v winding (unused), put that transformer into the integrated amp, and fit the replacement transformer to the 8P.
The problem is very simple...
You got the amp from the UK right ? So transformer is a 230/240V unit.
From you picture the transformer is a simple primary coil (Blue/orange wire on pcb connector).
Changing the fuse is not going to do anything because the TR is 240V and you want to supply 110V so output is 28/0/28 with 240V and you get around 12/14/0/14/12V with the 110V supply.
You have 2 choices, the first is more expensive and is a replacement transformer with the correct rating.
The second one is a step up transformer from 110v to 220/240V.
Very simple the Amp needs 240V on the plug to work and anything else is a no no.
PS. why do some people like to make simple things so confusing ?
Ric
You got the amp from the UK right ? So transformer is a 230/240V unit.
From you picture the transformer is a simple primary coil (Blue/orange wire on pcb connector).
Changing the fuse is not going to do anything because the TR is 240V and you want to supply 110V so output is 28/0/28 with 240V and you get around 12/14/0/14/12V with the 110V supply.
You have 2 choices, the first is more expensive and is a replacement transformer with the correct rating.
The second one is a step up transformer from 110v to 220/240V.
Very simple the Amp needs 240V on the plug to work and anything else is a no no.
PS. why do some people like to make simple things so confusing ?
Ric
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