'AK Mods' SC Class A 15W Amplifier

[Deleted]

Hi Alex,
have a chat with your friendly "Quack" I've managed to wangle some B12 injections for the rest of my life.
They certainly buck you up...............get a booster tomorrow morning so I'll probably be out dancing in the evening........................not :-/or even skipping like those bloody sheep.
Alan

[Deleted]

Dec 11, 2011 22:33:57 GMT drymdrum said:

Hi Alex,
have a chat with your friendly "Quack" I've managed to wangle some B12 injections for the rest of my life.
They certainly buck you up...............get a booster tomorrow morning so I'll probably be out dancing in the evening........................not :-/or even skipping like those bloody sheep.
Alan

Hi Alan
The Aussie versions of Vegemite and Marmite contain B12.
Seems that U.K. Marmite may not contain B12.
Apparently the liver stores B12. I am "a happy little Vegemite"
Regards
Alex

[Deleted]

Hi Alan

Brilliant work as usual, clearly I'm lacking in B12!

What Panasonic types are you using for normal and low ESR?

Syd

[Deleted]

Hi Syd,
I picked these



Panasonic EEUFM1C222 2200μF 16V dc 3190mA


Panasonic EEUFR1C222 2200μF 16V dc 2600mA - 0.018Ω

With regard to B12 neither Vegi....whatsit or Marmite are any use to me.............................................mmmmmmm! must ask Alex where he spreads it
I would dearly love to dispense with the bloody injections.
Regards,
Alan

[Deleted]

Dec 11, 2011 23:31:37 GMT drymdrum said:

Hi Syd,
I picked these
Panasonic EEUFM1C222 2200μF 16V dc 3190mA

Panasonic EEUFR1C222 2200μF 16V dc 2600mA - 0.018Ω

With regard to B12 neither Vegi....whatsit or Marmite are any use to me.............................................mmmmmmm! must ask Alex where he spreads it
I would dearly love to dispense with the bloody injections.

Thanks Alan, I have Panasonic of different types but not sure what constitutes 'low ESR' so good to look for a precise type.

Do we really want to know where Alex spreads his Marmite

Injections are a nuisance but think about how very important they can be.

Syd

[Deleted]

Do we really want to know where Alex spreads his Marmite Injections are a nuisance but think about how very important they can be.Syd

Syd

Faeces is reported to be a good source of Vitamin B12.
I wonder then, if bullshit is good for you ? ;D
Alex

[Deleted]

So that's why rabbits have so much energy!

Oysters are also stuffed with B12, though most meats and fish have it too.

Maybe Alex has a thing for Sticky Balls!

My mate, Marmite!

[Deleted]

I'd just love to see your faces eating Faeces

[Deleted]

Dec 11, 2011 12:26:43 GMT drymdrum said:

Hi Shaun,
quotes are from a PM from Frans to me you wont find them posted.
Perhaps I was wrong to post from a PM.......not sure on the etiquette of that..................so my apologies to you Frans .
However we, ......that's you and I Shaun......have our reply from Alex which helps us make a more informed decision on how to populate our PSU.............that has to be good.
As to the.....SUBS and OBS thing'y I doubt if any RG member is wholeheartedly one or the other .................in Frans case I have always viewed his use of the word......... "Subjectivist" with regard to Alex............. more a term of endearment than anything else .
Take care,
Alan

Hi Alan

I've had a few problems logging in so sorry for the late reply.

yup your dead right re the making informed choices re psu components and board population.

I've been having a look at the data sheets for the the LT1085/LT1033 and it seems that they are not quite identical.

I've read that need for protection diodes is a case in point.

1085 data sheet says no need for them.

1033 data sheet says to use them at higher currents and voltages.

so now I'm a little confused.

any idea?

my board is still at the drawing stage but I've decided to go with a chemical fix and try to etch. I've had a look at the original board layout and cant find a better grounding arrangement that the nice star ground used.

so rather than fiddling for ages to find a better way I've altered the original board overlay to use AS A template. I've just taken out the unused power transistors and UN needed components.

mmmm that press and peel method that you outlined looks pretty good for this kind of simple circuit so I'll try that out for sure.

so full has-chem suit on order and bunker dug and ready.

my first etch and I'll be delighted if i end up with anything other that a blank bare board.

it's a slow process but I'll keep you posted.

should be fun

take care

[Deleted]

Dec 11, 2011 23:31:37 GMT drymdrum said:

Hi Syd,
I picked these



Panasonic EEUFM1C222 2200μF 16V dc 3190mA


Panasonic EEUFR1C222 2200μF 16V dc 2600mA - 0.018Ω

With regard to B12 neither Vegi....whatsit or Marmite are any use to me.............................................mmmmmmm! must ask Alex where he spreads it
I would dearly love to dispense with the bloody injections.
Regards,
Alan

Alan
Both these types appear to be low ESR . Both are stated as .018
The attached is suitable for the normal type, and cheaper.
Alex

australia.rs-online.com/web/p/aluminium/1936770/

[Deleted]

Hi Alex,
once again you keep us right.................looked at the data sheets for both..........
I note that ESR is not quoted but Impedance is are they similar?
FR and FM series are Low ESR.
The ones I've got are good for 105c .... and a long life..........the Rubycons are 85c

Panasonic EEUFR1C222 2200μF 16V dc 2600mA - 0.018Ω
Panasonic EEUFM1C222 2200μF 16V dc 3190mA Impedance: 0.015ohm FM Series

Syd,
sorry I mislead you there..........but Panasonic FM and FC and FR are all Low ESR.

Alan

[Deleted]

Hi Alan
The normal type usually do not quote the impedance at 100kHz
which is what these figures are. Both types you mention would be classed as low ESR. 85c electros will not be a problem here, as the temp. in the case is unlikely to be even half that, and especially in the butt freezing part of the world you guys live in! ;D
My PSU's 5,600uF electros would be 85c due to their age, and are still fine nearly 13 years on.
Kind Regards
Alex

[Deleted]

Hi Shaun,
how are you applying your circuit to etch the copper.
I have reposted my PSU layout as I'd a couple of errors......thanks for drawing my attention to the LT1033 again as I'd pins for Vin and Vout reversed......fixed that also moved the Regs to the board end rather than two sides so both versions are now posted here.
If you flip a positive Reg layout to use as a Negative Reg layout with the JLH it messes some bits up so you have to take care especially with the BC550's/ BC560's and BC639/640...........where they face left on the positive side they are facing right on the negative.
Regards,
Alan

[Deleted]

[Deleted]

REGS PUSHED OUT TO THE END AND IN LINE

[Deleted]

butt freezing part of the world you guys live in!

Hey Alex,
don't decry something you ain't tried
anyway I like it fresh.....the cooler air keeps you fresh and fills your lungs better.
I've a distant cousin in Saskatchewan who reported in yesterday with a -21c now that's butt freezing.

Can't say thirty to forty above is pleasant especially with the sweat pouring.
Take care old friend and enjoy what you got. ;D
Shit it's freezing up here
Alan

[Deleted]

Hey Alex,don't decry something you ain't tried

Hi Alan
I think that my father's family may have had more than future employment prospects in mind when they migrated here from Scotland!
I must admit that I would have liked to visited Scotland , but I have left it too late now.BTW, I have been told that when I was very young I had a broad Scottish accent.
Regards
Alex

[Deleted]

Syd,sorry I mislead you there..........but Panasonic FM and FC and FR are all Low ESR.Alan

No worries Alan, noticed Alex's caution. I'll take care when I get back to actually stuffing these boards.

I'm impressed by Chris's implementation

Syd

[Deleted]

Hi Syd,
Me too.
Alan

[jeffc]

Hi Guys,

Seeing you're all progressing PSUs at a great rate, particularly blooody Alan , gung ho and top stuff , I've been thinking these Audiowind PCBs I used in the Class A HA should work for the PA too OK with regulators provided additional heat sinking. Anyone see potential issues that I can't?. They're quite well made with generally wide tracks suitable for up to 3A continuous current or so.

www.ebay.com.au/itm/Voltage-Regulator-PCB-LM317-LM337-78xx-79xx-IC-1PCS-/130602867766?pt=LH_DefaultDomain_0&hash=item1e68899c36

And as with other JLHs I've used in various apps, can 10V or even 6.3V 2200uf caps be used? If have a stack of these but none rated for 16V .

cheers.. jeffc

[Deleted]

Hi Jeff,
Will's got official PCB board on the stocks probably best to wait for that..............just give him time.
S'allright for that "bloody Alan" he's got time to spare...........with eight years retirement under his belt.
Drymdrum.

[Will]

Hi Guys,

Sorry for going quiet on you, had a bad case of 'real life' Nothing serious, just very busy.

Here's a look at how the PSU is looking.



It still needs a bit of work (track thickening, compaction and stuff) but it roughly there. It's based on the LT1085/LT1033 (with safety diodes due to potential cap sizes) but it will also work with LM317/337 regs.

[Will]

Alan,

Your PSU's are looking excellent! Good stuff!

[Deleted]

Dec 13, 2011 20:46:52 GMT Will said:

Hi Guys,

Sorry for going quiet on you, had a bad case of 'real life' Nothing serious, just very busy.

Here's a look at how the PSU is looking.



It still needs a bit of work (track thickening, compaction and stuff) but it roughly there. It's based on the LT1085/LT1033 (with safety diodes due to potential cap sizes) but it will also work with LM317/337 regs.

Hi Will

hows it going?

nice work on the PSU and looking good on the star front.

just one question.

looks like you have the OP caps bypassed but after reading the 1033 data sheet it seems a little sensitive too low ESR in that position and also distance (impedance to the load from the reg.

also the data sheet for the LT1085 has built in protection so those diodes are maybe not needed but do seem to be for the 1033.

that circuit looks like a chip off of the old block of the original but soooo much more elegant.

well done on that.

i may have things wrong but would like to learn.

did my first etch today based on the original artwork minus the UN needed stuff component wise. came out better than expected and was great fun almost like developing a picture.

take care

[Deleted]

Hi All

just to keep this available.

for the LS device GB so far i have

Will 2x LS352 and 2X LS313
Phil 2x LS352 and 2X LS313 (provisional)
Me 2x LS352 and 2X LS313
Syd 2x LS352 and 2X LS313
Alan 2X LS352 and 2X LS313
Alex 2X LS352 and 2X LS313
Mark 2X LS352 and 2X LS313 (cyteen)
Jeff 2X LS352 and 2X LS313
Jon C 2X LS352 and 2X LS313

Kits GB

Chris
Syd
Phil
Will
mark (cyteen)
Jon C

Boards only GB

Alex
me
Alan

anyone else?

take care