(AK) classA HA/Preamplifier.

[FritzS]

Nov 25, 2010 12:41:03 GMT @shaun said:

good idea Will, i would be up for that

take care

oh yes before i forget ;D Last orders for this round of the great Jaycar extravaganza

i have orders from Mr Fritzs and Will so any one else interested let me know by Friday 26th Nov. i will be up for another order after Xmas so anyone having problems ordering from Jaycar will have another chance.

I contact RS, Distrelec, Farnell
RS Austria have MRS25 resistors, 1N5819, BZX55-C3V3 in their stock
only 2SA1930 & 2SC5171 in Austria not - but in Australia yes

[FritzS]

Alex,
whats recommend spare parts for
2SA1930 & 2SC5171

Which new BJT's comes close to 2SA1930 & 2SC5171 in performance?

[Deleted]

Nov 26, 2010 7:07:17 GMT FritzS said:

Alex,
whats recommend spare parts for
2SA1930 & 2SC5171

Which new BJT's comes close to 2SA1930 & 2SC5171 in performance?

Friedrich
I do not recommend replacements for those Toshiba devices.
In my experience they are very consistent in their HFE in both polarities.
This aids matching.
The 2SC5171 and 2SA1930 are readily obtainable from many sources, including matched pairs available on ebay.
Don't forget you will also need them for the JLH PCBs.
Alex

[FritzS]

Nov 26, 2010 7:16:29 GMT @sandyk said:

Nov 26, 2010 7:07:17 GMT FritzS said:

Alex,
whats recommend spare parts for
2SA1930 & 2SC5171

Which new BJT's comes close to 2SA1930 & 2SC5171 in performance?

Friedrich
I do not recommend replacements for those Toshiba devices.
In my experience they are very consistent in their HFE in both polarities.
This aids matching.
The 2SC5171 and 2SA1930 are readily obtainable from many sources, including matched pairs available on ebay.
Alex

Could you recommend me a special source on eBay?
I am very carefully about eBay

I don't want to get fakes or gingerbreads ;D

matched pairs are needed - in JLH too?

[Deleted]

Nov 26, 2010 7:23:18 GMT FritzS said:

Nov 26, 2010 7:16:29 GMT @sandyk said:

Friedrich
I do not recommend replacements for those Toshiba devices.
In my experience they are very consistent in their HFE in both polarities.
This aids matching.
The 2SC5171 and 2SA1930 are readily obtainable from many sources, including matched pairs available on ebay.
Alex

Could you recommend me a special source on eBay?
I am very carefully about eBay

I don't want to get fakes or gingerbreads ;D

matched pairs are needed - in JLH too?

I can't recommend any ebay source that currently has them, although I have previously bought some from ebay..
You do not need matched Toshiba devices for the JLH.

A check of the RS Components Australian website says that they are both in stock globally, and will be delivered within 6-8 working days .
They are supplied in packs of 5.

Also

audiolabga.com/mal_cart/mal_cart.php?find=2sc5171

is a good reliable supplier, as is Electronics Salon (Audiowind).
stores.ebay.com.au/Electronics-Salon/_i.html?_nkw=2SC5171&submit=Search&_sid=804830199

[Will]

Hi Friedrich

Several of us here have bought the toshibas from myworld.ebay.co.uk/audiowind-2005/ which do appear to be the real thing. Good value as well.

I've linked to matched pairs of the toshibas a page back, but have not bought any.

As for the JLH's, the Q2 and Q3 transistor do benefit from good matching, as do R5&R7 (new GB PCB's). If you want to get super OCD about things, matching the toshibas (and everything else!) between the same location on the +ve and -ve board is the way to go (like wot i did!)

[XTRProf]

Nov 26, 2010 7:35:43 GMT Will said:

If you want to get super OCD about things, matching the toshibas (and everything else!) between the same location on the +ve and -ve board is the way to go (like wot i did!)

Yeah, me too in the American spirit!

[XTRProf]

Yeah, how do we tell the real Toshiba from the fake?

[XTRProf]

Nov 25, 2010 8:50:55 GMT Will said:

The resistor model I've used for the PCB layout is based on the Vishay MRS25, 0.6W body. (207/10mm pitch, full details in the link in the BOM)

I chose these as they are a good GP resistor that are about £2 for 50. They also normally come at the same value (little variance from the stated value) in the same strip.

I've also placed 3.8mm pitch holes on the input, feedback and output resistor, if you fancy trying them naked foil jobs.

Any normal 1% 0.5/0.6 metal film resistor should be good to go. Just ensure that they are not too big, otherwise you'll end up tomb-stoning.

I just have a look at the Vishay MRS25 and it seems that these resistors are also copper leads. The description goes like this:



DESCRIPTION
A homogeneous film of metal alloy is deposited on a high
grade ceramic body. After a helical groove has been cut in
the resistive layer, tinned connecting wires of electrolytic
copper are welded to the end-caps. The resistors are coated
with lacquer which provides electrical, mechanical, and
climatic protection. Four or five color code rings designate
the resistance value and tolerance according to IEC 60062.
Suitable replacements for MRS16 and MRS25 are
MBA/SMA 0204 and MBB/SMA 0207 professional.



For all info ...........

[XTRProf]

Nov 25, 2010 5:48:45 GMT @sandyk said:

Mine is in a 1U rack case as per the photo.



Uploaded with ImageShack.us

Oh, seems we really new quite a big box to house the stuff.

Thanks as that will give use roughly what box or boxes (if we go highend) to get.

[Deleted]

Nov 26, 2010 8:14:20 GMT XTRProf said:

Nov 25, 2010 8:50:55 GMT Will said:

The resistor model I've used for the PCB layout is based on the Vishay MRS25, 0.6W body. (207/10mm pitch, full details in the link in the BOM)

I chose these as they are a good GP resistor that are about £2 for 50. They also normally come at the same value (little variance from the stated value) in the same strip.

I've also placed 3.8mm pitch holes on the input, feedback and output resistor, if you fancy trying them naked foil jobs.

Any normal 1% 0.5/0.6 metal film resistor should be good to go. Just ensure that they are not too big, otherwise you'll end up tomb-stoning.

I just have a look at the Vishay MRS25 and it seems that these resistors are also copper leads. The description goes like this:



DESCRIPTION
A homogeneous film of metal alloy is deposited on a high
grade ceramic body. After a helical groove has been cut in
the resistive layer, tinned connecting wires of electrolytic
copper are welded to the end-caps. The resistors are coated
with lacquer which provides electrical, mechanical, and
climatic protection. Four or five color code rings designate
the resistance value and tolerance according to IEC 60062.
Suitable replacements for MRS16 and MRS25 are
MBA/SMA 0204 and MBB/SMA 0207 professional.



For all info ...........

But do they go up like a lighted match when overloaded ?

[XTRProf]

Nov 26, 2010 9:34:22 GMT @sandyk said:

Nov 26, 2010 8:14:20 GMT XTRProf said:

I just have a look at the Vishay MRS25 and it seems that these resistors are also copper leads. The description goes like this:



DESCRIPTION
A homogeneous film of metal alloy is deposited on a high
grade ceramic body. After a helical groove has been cut in
the resistive layer, tinned connecting wires of electrolytic
copper are welded to the end-caps. The resistors are coated
with lacquer which provides electrical, mechanical, and
climatic protection. Four or five color code rings designate
the resistance value and tolerance according to IEC 60062.
Suitable replacements for MRS16 and MRS25 are
MBA/SMA 0204 and MBB/SMA 0207 professional.



For all info ...........

But do they go up like a lighted match when overloaded ?

Really, I dunno? Maybe check out Vishay equivalent MBA/SMA 0204 and MBB/SMA 0207 professional which may be even higher rating.

[Deleted]

Nov 26, 2010 7:23:18 GMT FritzS said:

Nov 26, 2010 7:16:29 GMT @sandyk said:

Friedrich
I do not recommend replacements for those Toshiba devices.
In my experience they are very consistent in their HFE in both polarities.
This aids matching.
The 2SC5171 and 2SA1930 are readily obtainable from many sources, including matched pairs available on ebay.
Alex

Could you recommend me a special source on eBay?
I am very carefully about eBay

I don't want to get fakes or gingerbreads ;D

matched pairs are needed - in JLH too?

Hi Fritzs

I've used audiowind for these for my SCHA the seem like the real thing.

I've ordered some more from them

take care

[Deleted]

Hi All

Mr Fritzs and Will

I've had a few problems ordering the suntans from Jaycar. I've tried using the link provided by will to find them. that was fine and dandy. when i checked my basket before committing to order ''gods dam it'' the brand had changed from suntan to Saxon (never trust a Saxon thats my motto ). I've gone ahead with the 100uf caps for Will and the 2x psu kits for Fritzs but I'm stuck for how to order the magic suntans.

maybe suntans are only allowed in Aus. but the name just makes me envious.

any ideas would be great

take care

[FritzS]

2SC5171 and 2SA193

Alex,
how close should they matched for the amp?

If I count right, for this amp & JLH's there are 8 pcs needed of each.

If I buy 10 pcs. of each is there enough to get two pairs and some closer for the JLH's!?

[Deleted]

Hi Shaun

I remembered Alex mentioning these before:

Quote: Re: Extreme X-DAC v3 mods by sandyK
Post by sandyk on 29 Apr, 2010, 9:31pm


29 Apr, 2010, 12:55pm, juke wrote:

The JLH as shown has now been upgraded to use 2 x 4,700uF 10V low ESR capacitors in parallel per supply rail instead of the original 2 x 2,200uF


Hi Alex

Is this now standard for JLHs or just in the X-DAC, I presume Suntans again?

Any point or problem using higher voltage so that only one stock of caps necessary? I haven't found Suntans anywhere but Australia.
Thanks, Syd


Hi Syd
The difference is only small when changing to the 4,700uF, but I feel it is worthwhile,especially when using any JLH at a higher current than 100mA.
You can use 10V or 16V low ESR types. Even 25V may be O.K. these days, but make sure they aren't physically too large to fit the PCB. Stay clear of the so called "Audio" types, as they are usually less than neutral sounding.Samxon is another very good brand that I have tried. Alex

I sent to Australia anyway at the time and it was Samxons that came back, but wasn't worried because of above.

Syd

[Deleted]

Nov 26, 2010 14:52:27 GMT @juke said:

Hi Shaun

I remembered Alex mentioning these before:

Quote: Re: Extreme X-DAC v3 mods by sandyK
Post by sandyk on 29 Apr, 2010, 9:31pm


29 Apr, 2010, 12:55pm, juke wrote:

The JLH as shown has now been upgraded to use 2 x 4,700uF 10V low ESR capacitors in parallel per supply rail instead of the original 2 x 2,200uF


Hi Alex

Is this now standard for JLHs or just in the X-DAC, I presume Suntans again?

Any point or problem using higher voltage so that only one stock of caps necessary? I haven't found Suntans anywhere but Australia.
Thanks, Syd


Hi Syd
The difference is only small when changing to the 4,700uF, but I feel it is worthwhile,especially when using any JLH at a higher current than 100mA.
You can use 10V or 16V low ESR types. Even 25V may be O.K. these days, but make sure they aren't physically too large to fit the PCB. Stay clear of the so called "Audio" types, as they are usually less than neutral sounding.Samxon is another very good brand that I have tried. Alex

I sent to Australia anyway at the time and it was Saxons that came back, but wasn't worried because of above.

Syd

Hi Spirit

thanks for the info on the Saxons it's really useful. OK I'll email Will and Fritzs before ordering just to make sure there are no objections from them.

take care

[FritzS]

Nov 26, 2010 15:22:46 GMT @shaun said:

Hi Spirit

thanks for the info on the Saxons it's really useful. OK I'll email Will and Fritzs before ordering just to make sure there are no objections from them.

shaun
What did they cost?

[Deleted]

Nov 26, 2010 15:30:10 GMT FritzS said:

Nov 26, 2010 15:22:46 GMT @shaun said:

Hi Spirit

thanks for the info on the Saxons it's really useful. OK I'll email Will and Fritzs before ordering just to make sure there are no objections from them.

shaun
What did they cost?

Hi Fritzs

i think that the Samson Caps are the same price as the suntans so if you want some let me know. Your PSU kits are on order so it's just waiting for them to turn up.

take care

[Deleted]

Nov 19, 2010 17:35:36 GMT @shaun said:

Nov 19, 2010 16:56:13 GMT FritzS said:

I am interested for two ... for pcs.

Please send me a PM

Where you live?

Hi Fritzs

OK thats going to be no problem. I'll put you on the list. you are going to need 8 of 4700 magic suntan caps for the JLH also.

prices in good old UK pounds are

PSU Boards £5.25 each for nice boards and most of the parts required. for +5

4700uf 10v low esr caps £0.47p each for +10

both plus P.P and the possibility of import duty but i paid nothing last time so we will see.

some prices may go down if we have enough interest.

fritzs

I'm happy to stand the cost of your order and when it turns up here we can sort it out then. if the numbers get to big then it's pay up front time. the last order i had from them took just over 7days to arrive then there will be the post on time. don't worry about payment for now till i cry for help it's gonna be just fine.

for now I'm happy

I'll keep the list open for a week so any one who wants to jump in fell free. we have a VAT rise here in the UK so i want to get this one done before that happy day.

weeee're sinking fast.

take care

Hi Fritzs

here are the prices.

take care

[Deleted]

i think that the Samson Caps are the same price as the suntans so if you want some let me know.

Do you mean Samxon ?
Jaycar used to stock those.
They appear to have a good reputation.
Alex

[Deleted]

Nov 26, 2010 13:14:21 GMT FritzS said:

2SC5171 and 2SA193

Alex,
how close should they matched for the amp?

If I count right, for this amp & JLH's there are 8 pcs needed of each.

If I buy 10 pcs. of each is there enough to get two pairs and some closer for the JLH's!?

Friedrich
Most of those that I have received have HFE between 170 and 220.
This will of course vary with the actual transistor tester used and the Collector current range used.
Just try to get 2 fairly well matched pairs for the amplifier and use the others for the JLHs.If you want to be a perfectionist, you will need to order a few more.
Alex

[FritzS]

Most of those that I have received have HFE between 170 and 220. This will of course vary with the actual transistor tester used and the Collector current range used.Just try to get 2 fairly well matched pairs for the amplifier and use the others for the JLHs.If you want to be a perfectionist, you will need to order a few more.Alex

I must make a HFE tester self, I have some constant current sources (2 .... 5mA) too. My digital meter does not have a BJT test range.

[Deleted]

Nov 26, 2010 7:07:17 GMT FritzS said:

Alex,
whats recommend spare parts for
2SA1930 & 2SC5171

Which new BJT's comes close to 2SA1930 & 2SC5171 in performance?

2SB1274 / 2SD1913 (Farnell: 1790447 / 1790446 )
easier to get Sanyo transistors that will perform very well too.
Isolated TO-220ML housing.
Can also be used in Panda output stage should you want 'modern' devices that reach 100MHz.
Not that the Panda or any other amp with these output transistors will get any faster as the 'speed' of the amplifier is determined by the feedback being at a much lower frequency.

data sheet: semicon.sanyo.com/en/search/property.php?clcd=124&prod=2SD1913

the 2SA1930 & 2SC5171 reach 200MHz and have higher Vce voltages

[Deleted]

Nov 27, 2010 9:32:28 GMT @solderdude said:

Nov 26, 2010 7:07:17 GMT FritzS said:

Alex,
whats recommend spare parts for
2SA1930 & 2SC5171

Which new BJT's comes close to 2SA1930 & 2SC5171 in performance?

2SB1274 / 2SD1913 (Farnell: 1790447 / 1790446 )
easier to get Sanyo transistors that will perform very well too.
Isolated TO-220ML housing.
Can also be used in Panda output stage should you want 'modern' devices that reach 100MHz.
Not that the Panda or any other amp with these output transistors will get any faster as the 'speed' of the amplifier is determined by the feedback being at a much lower frequency.

data sheet: semicon.sanyo.com/en/search/property.php?clcd=124&prod=2SD1913

the 2SA1930 & 2SC5171 reach 200MHz and have higher Vce voltages

Frans
My main reason for specifying the Toshiba 2SA1930 and 2SC5171, is the consistency between genuine Toshiba devices.
Nearly all of these Toshiba devices that I have tested, are normally within the HFE range of 170 to 220 with my Transistor tester. This is a far cry from devices like the ubiquitous BD139 and BD140.
This means that excellent results will be achieved even if they are not matched, as some members are unable to do this.
Alex