Check out the build that appears in Everyday Practical Electronics Jan. 18.
A worthy build.
200W RMS into 4 ohms, 135W RMS into 8 ohms.
All information available here.
EPE Magazine January 2018
Article first appeared here: -
New SC200 Audio Amplifier - January 2017 - Silicon Chip Online
A worthy build.
200W RMS into 4 ohms, 135W RMS into 8 ohms.
All information available here.
EPE Magazine January 2018
Article first appeared here: -
New SC200 Audio Amplifier - January 2017 - Silicon Chip Online
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It's an Australian Silcon Chip Design
This is an Australian Silicon Chip design (Nicholas Vinen and Leo Simpson, January 2017 issue). Looks to be a robust low-distortion 135W/8ohm Blameless inspired class AB amp. Uses On Semiconductor FJA4313/FJA4213 output devices.
For those Ozzies/Kiwis who are keen, a single channel kit and heatsink is about $130 AUD from Altronics. Jaycar should be stocking kit as well. The PCB is available from the Silcon Chip on-line shop for $10 AUD.
Will be expensive (compared to Class D) to build a complete amplifier, when you include power supply, protection and enclosure. SC480 is still available for those with more modest requirements and budgets.
Regards ...
This is an Australian Silicon Chip design (Nicholas Vinen and Leo Simpson, January 2017 issue). Looks to be a robust low-distortion 135W/8ohm Blameless inspired class AB amp. Uses On Semiconductor FJA4313/FJA4213 output devices.
For those Ozzies/Kiwis who are keen, a single channel kit and heatsink is about $130 AUD from Altronics. Jaycar should be stocking kit as well. The PCB is available from the Silcon Chip on-line shop for $10 AUD.
Will be expensive (compared to Class D) to build a complete amplifier, when you include power supply, protection and enclosure. SC480 is still available for those with more modest requirements and budgets.
Regards ...
Do you know what transformer voltage they used for the 135W into 8ohms output?
With a dual 35Vac I usually get between 100W and 120W into 8r0 and for a dual 40Vac get between 155W and 175W into 8r0.
45-0-45 VAC transformer output
The recommendations quoted on page 85 of February 2017 Silicon Chip Magazine are:
45-0-45 VAC transformer output. 300 VA for normal domestic use with 2 channels. 500 VA for heavy continuous output from 2 channels. Nominal rail voltage is +/- 57VDC.
Regards ...
The recommendations quoted on page 85 of February 2017 Silicon Chip Magazine are:
45-0-45 VAC transformer output. 300 VA for normal domestic use with 2 channels. 500 VA for heavy continuous output from 2 channels. Nominal rail voltage is +/- 57VDC.
Regards ...
Nominal +-57Vdc supplies come from a dual 40Vac transformer.
And a dual 40Vac transformer should allow any decent amplifier design build to reach in excess of 150W into 8r0.
I got 171W, or 174W into 8r0 from a 230:dual 40Vac transformer fed from 240Vac, single channel driven and unclipped sinewave output.
And a dual 40Vac transformer should allow any decent amplifier design build to reach in excess of 150W into 8r0.
I got 171W, or 174W into 8r0 from a 230:dual 40Vac transformer fed from 240Vac, single channel driven and unclipped sinewave output.
Kit and DIY assembly recommendations depend very much on the free availability of suitable stock standard, local retail parts. If constructors were expected to optimise kit designs for themselves so that they arrived at maximal textbook figures for their builds, there wouldn't be much DIY going on - perhaps just a handful of retired techs and engineers looking to remain competitive in each endeavour.
I believe that kit designers should accommodate available, if perhaps undersized heatsinks and transformers as well as the optimal choices, depending on the kitseller and their sources. Custom parts for kits are just no longer viable and this means designers will likely need to under-rate their electronic designs accordingly. In our Oz market, many constructors in all branches of electronics, are going to be young, first or second time builders. Nobody wants them to fail at the first hurdle because they know zip about electronics and this is a big project. They only need to follow the articles or duplicated guide, connect the dots, it still meets the specs and almost everyone is happy without sweating over technical issues. So it has been here since the 1970s, when I shifted my interest to audio
Hi,
reading the articels is always helpful
.See EPE Magazin:
The transformer specification should be 40-0-40 not
45-0-45V.
BR
Gunni
Exactly why I mentioned it had appeared in the Silicon Chip, good on our friends from down under.
Before questions are asked, read the article, no point in putting a spanner in the works by those who havent even read it.
Looks a great project to build!
Might pay to read the original Silicon Chip Articles
Yes it does help to read the three Silicon Chip articles and examine the power supply schematic as well. The Silicon Chip article specifies 45-0-45 transformer connected to an Altronics K5168 with an external bridge which then powers the amplifier. You can of coarse use your own alternatives to power the amplifier.
So you are going to build this amplifier?
Yes it does help to read the three Silicon Chip articles and examine the power supply schematic as well. The Silicon Chip article specifies 45-0-45 transformer connected to an Altronics K5168 with an external bridge which then powers the amplifier. You can of coarse use your own alternatives to power the amplifier.
So you are going to build this amplifier?
Hmmm I can't see it.
Well, could you please tell me on which page does the article refers to a 40 volt transformer output? My eyesight must be failing ...
Hi,
reading the articels is always helpful
See EPE Magazin:
Well, could you please tell me on which page does the article refers to a 40 volt transformer output? My eyesight must be failing ...
In the Australian Silicon Chip magazine (Nicholas Vinen and Leo Simpson, January 2017 issue) and Everyday Practical Electronics (reproduced by arrangement with Silicon Chip magazine Jan. 18 issue) this project is very well explained.
Full details are there to be read before the 'if and 'but' appears by the non-reader.
E.P.E. Feb. 18 will appear full details of performance and construction.
Silicon Chip Online
www.epemag.com EPE Everyday Practical Electronics hobby constructor magazine
Full details are there to be read before the 'if and 'but' appears by the non-reader.
E.P.E. Feb. 18 will appear full details of performance and construction.
Silicon Chip Online
www.epemag.com EPE Everyday Practical Electronics hobby constructor magazine
Please read the article!
EPE Magazine February 2018
It very clearly states the transformer to use..........
A 40-0-40 not 45-0-45V
Let's get reading...
EPE Magazine February 2018
It very clearly states the transformer to use..........
A 40-0-40 not 45-0-45V
Let's get reading...
What Worked for me on my computer linux OP browser google chrome. And on android 8 Phone.
I'm reading .... where is it?
Everyday Practical Electronics, February 2018, Page 30, in the middle column:
Power supply
The power supply requirements for this module are optimal with supply rails of ±55-60V, nominally ±57V, from a 45-0-45 transformer. We will present the details next month.
Where the heck are you finding 40-0-40? I can't find it in the EPE or Silicon Chip articles.
Anyway I think the quoted power of 135 Watts might be a bit conservative. Maybe with a 45-0-45 160 VA transformer powering two amps. The Tortech 160 VA transformers have about 9% regulation. The voltage they quote is for no load. I'm already using a couple in another build.
Everyday Practical Electronics, February 2018, Page 30, in the middle column:
Power supply
The power supply requirements for this module are optimal with supply rails of ±55-60V, nominally ±57V, from a 45-0-45 transformer. We will present the details next month.
Where the heck are you finding 40-0-40? I can't find it in the EPE or Silicon Chip articles.
Anyway I think the quoted power of 135 Watts might be a bit conservative. Maybe with a 45-0-45 160 VA transformer powering two amps. The Tortech 160 VA transformers have about 9% regulation. The voltage they quote is for no load. I'm already using a couple in another build.
The Silicon Chip site is always locked for access at the first page of an article etc. They have online subscriptions and article photocopying services too, so that figures. The EPE site, where the syndicated construction articles reappear 12 months later, is open for all pages, albeit a little difficult to read.
My PC setup is just the typical Windows 10/Google Chrome browser one, so I expect others have at least my level of access unless you have a quirky OS and browser that weren't intended for today's intensive multimedia use and searches.
BTW, Toroidal transformer voltage ratings are at full rated power, so regulation is irrelevant but in any case, 45VAC windings are going to give a lot more than 57VDC unregulated. It's just wrong or was intended for a higher supply as perhaps for just 8R loads, since the 2 pairs of lightweight output transistors will have a hard time up there.
My PC setup is just the typical Windows 10/Google Chrome browser one, so I expect others have at least my level of access unless you have a quirky OS and browser that weren't intended for today's intensive multimedia use and searches.
BTW, Toroidal transformer voltage ratings are at full rated power, so regulation is irrelevant but in any case, 45VAC windings are going to give a lot more than 57VDC unregulated. It's just wrong or was intended for a higher supply as perhaps for just 8R loads, since the 2 pairs of lightweight output transistors will have a hard time up there.
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