All things G1176 - the new "repost" thread.

[byoung]

I've spent the day stuffing my Mnats board and have a couple questions before I can continue.

1) where is R50? on Mnats BOM it says it is not used on the gyraf version and I can see it on any of the boards? It's an 8.2K

2) on Mnats BOM he lists 2 220pF ceramic caps at locations C3, C4(where the schematic say 200p)also a few parts down on his BOM he lists 1 220pF ceramic cap at location C32. So should I use the same 220p caps for all three locations?

3) I used Gregs BOM to actually order from, and there are 220p 5mm 50v poly caps, and 220p 100v ceramic caps, So this is in reference to question #2, where do these different caps go? I've tried looking at the schematic to figure this out but am still a little confused.

4) Also on Mnats BOM there are 47uF electrolytic caps at locations C9, C11, C34, and then there is a listing for a 47uF/35V electrolytic at C18. I'm assuming I can use 47uF/35V at all these locations?

Thanks
Brian

 

[astrovic]

G'day Brian

As best as I can:

1) R50 doesn't go anywhere, in either the Gyraf or the Mnats boards. I think previous posts have explained the history of R50.

2 & 3) C3, C4 and C32 all can use the same ceramic capacitor - the 50v should be fine. I used them for C3 and C4 (I haven't installed C32 as I used the transformer input approach, but the same cap should work)

4) 47uF/35v works at all locations - that's what I did

Hope this helps!

 

[khstudio]

I looked for these answers but couldn't find what I wanted...

(I'm using the MNATS New version board)
I know SOME of the (*) components are needed when using the input tranny but there are others in the Gyraf version. Mnats says he doesn't install them but I've seen others, like Greg for instance, installing them even without an input tranny... WHY?

Could some one explane what they're there for?

For instance, the 1000uf/35v next to the 2.2k trimmer... for one thing, a 1000uf/35v cap doesn't even fit in this spot, especially on my Mnats board :?

Could someone shed some light on this?

Why are they optional & what do they do... in or out of the circuit?
I'm using the BD135/136 output trasistors if that makes any difference.

Thanks,
Kevin

 

[gyraf]

Hi Kevin,

If you compare the schematic and the layout, everything should be clear. Nothing wrong in mounting all parts, just some may not really be needed.

Jakob E.

 

[glide 1]

Hi All,

I'm new to the boards aswell as DIY. I've recently purchased Mnats's boards and decided that the 1176 project would be my first attempt at DIY. I will be using a trnsformerless input and the OEP output trafo

I spent hours and hours the past few days reading every bit of info there is on the 1176, seems like the more i read though, the more i believe i can tackle this project......Crossing fingers AND toes!!!

I have a question. On Mnats' BOM, which Caps in particular would you recommend me spending money on? the prices range from a few cent to $5, and some even more. Is there actually an audible difference using expensive caps or is it more for reliability and better tolerances of the components in general. If someone could list these caps mentioned above , i would appreciate it a lot thanks.

There will be more questions later i'm sure, just thanking everyone in advance for all the knowledge you so readily give to us newbies....Mabuhay Prodigy!!!

glide 1

 

[astrovic]

G'day Glide - welcome aboard

The 1176 was my first major project, and it rocks (can I show it off?). Prior to starting I read a lot of threads discussing other people's completed builds, and decided to settle on Nichicon PW electrolytics and Panasonic ECG for most of the others. WIMA is a popular brand as well around these parts.

I don't think you need to go as high as $5 to get decent quality caps, though.

Try doing some searches on "WIMA" and "Nichicon" and browse some of the posts, as these searches will throw up a lot of results where the qualities of various caps are discussed, by people far more qualified to do so than me.

If you haven't seen it yet, have a look at Greg's BOM's as they are just brilliant. Just looking at his BOM for the 1176, I see I used the caps listed there, and I don't think that was an accident :grin: My unit rocks, so those caps must be good :thumb:

Finally, is this your first ever project? If so, you might want to have a crack at something a little simpler first to "get your eye in". My first build was a DI box using a JLM di kit (as per Kev's JLM Simple DI page), then a PAIA tube mic pre kit, before trying the G1176. I'm very glad I started with the simple stuff first!

Welcome to DIY!

Chris

PS Yes, I am enjoying do the think with the links to other pages by clicking on the text. Just figured how to do it!

 

[MattiasC]

I'd like to chime in here since I just finished my first G1176 (which I'm loving).

Before this project I'd only done small DIY projects, all of which allowed me to get away WITHOUT reading the schematic. Not so with the G1176. With this one I was FORCED AGAINST MY WILL to learn how to read it.

If you haven't sat down with the schematic to learn what's going on, you really owe it to yourself to get this out of the way before you continue. I promise you will be happier you did, and you will spend much, much less time searching the forums.

Good luck!

 

[glide 1]

The 1176 was my first major project, and it rocks (can I show it off?). Prior to starting I read a lot of threads discussing other people's completed builds, and decided to settle on Nichicon PW electrolytics and Panasonic ECG for most of the others. WIMA is a popular brand as well around these parts.


astrovic, MattiasC,


Yes the ECG's, Nichicons and Wima's i've seen being mentioned here a lot, will look into that. The "Bemble 1176" i did see too....looks very nice. i might opt for the OEP input aswell later on. I have Greg's and Mnats' BOMs printed out, so will be basing my parts purchase on these.

Before this project I'd only done small DIY projects, all of which allowed me to get away WITHOUT reading the schematic. Not so with the G1176. With this one I was FORCED AGAINST MY WILL to learn how to read it.


I'm in the same situation as you, very minor repairs on gtr amps, efx pedals etc. - no real DIY projects under my belt as such - yet. With this 1 however, i've talked to a friend already about helping me build. So much to learn and i'm very exited!!


Thanks for the welcome and advice guys...much appreciated

glide 1

 

[Guest]

Hi guys and gal's!

This will be my first post here (but certanly not the last), and i must say it feels good!

I finished my 1176LN clone this weekend.
I fierd it up (holding my breath anticipating things to start smoking).
Belive it or not, IT WORKED!!!!! :grin:
No, hum, noise and other bad things.
This is my first project that has been without ANY bugs.

BIG thanx to Mr Gyraf and Mr MNats for a great design!!! :guinness: :guinness: :guinness: :guinness:

I have some questions though:

What is the purpose of having lowleakage diodes (FDH333)?
Some capacitors on MNats board are marked with asterisk, why?
I could not find any ifno on them.
Maybe i should look harder.

I will probably post a thread when i get the panel done.

Thanx 1k times again!


/Hampus

 

[gyraf]

Low leakage diodes are needed, because we want to keep the "floating" DC offset after the diodes undisturbed. This DC-potential is very High-Z. All leakage would draw the whole circut in the wrong direction.

Jakob E.

 

[khstudio]

[quote author="gyraf"]Hi Kevin,

If you compare the schematic and the layout, everything should be clear. Nothing wrong in mounting all parts, just some may not really be needed.

Jakob E.[/quote]

I realize that the extra parts are not needed I just wanted to know WHY they were added in the first place... what do they do? Like the 1000uf/35v electro that I couldn't fit on my board if I wanted to

I just want to learn, that's all.

& since you designed it I was hoping you could be more specific :green:
I can't be the only one who would like to know... am I :?

Kevin

 

[astrovic]

[quote author="cosmox"]
Some capacitors on MNats board are marked with asterisk, why?
I could not find any ifno on them.
Maybe i should look harder.
[/quote]

http://www.geocities.com/m_natsume/1176_FAQ.html - see the answer to the first question...

Otherwise - congrats! :thumb:

 

[khstudio]

[quote author="astrovic"][quote author="cosmox"]
Some capacitors on MNats board are marked with asterisk, why?
I could not find any ifno on them.
Maybe i should look harder.
[/quote]

http://www.geocities.com/m_natsume/1176_FAQ.html - see the answer to the first question...

Otherwise - congrats! :thumb:[/quote]

My point exactly... Mnats basically says they're not needed for a working clone.

I got that part :wink:

But there has to be a reason Gyraf put them there... that's what I would like to know. It's like - I can't make a decision about an optional component when I don't know what it does in the first place.

Just saying, go ahead and put them in (or not) doesn't make sense.

Kevin

 

[khstudio]

[quote author="gyraf"]Hi Kevin,

Nothing wrong in mounting all parts, just some may not really be needed.

Jakob E.[/quote]

Could you be more specific.
I really don't mean to be a pain in the ass, I'm just curious :green:

Kevin

 

[gyraf]

I don't really know the MNATS version in detail, but it looks like e.g. C*1 is additional psu stabilisation. And that is always a good thing.

Jakob E.

 

[Guest]

Thanx for the earlier replys.

Now I have some questions about the VU meter.
Since i have a hard time getting hold of nice looking VU meters I'm thinking of using an A-meter (mA).

What is the prefered internal resistanse for a A-meter?
How does the rectification work, how is it hooked up?
What is the inpact of rectification resistance?

Regards/

Hampus

 

[dukasound]

Excuse me if I missed
Phase on output transformer (Lundahl) of Mnats and Jacobs project are diferent.

 

[W DeMarco]

Hey folks

Im real excited to see that the voltages on the regulator are all clean and Im passin audio through my new 1176. I noticed on the oscope a strange waveform on VU mode. Excuse the error in the pic as I mixed up bypass and vu mode. This appears when set to vu mode. Wondering if anyone can shed some light on this. Pics at http://www.vuturevisions.com/g1176/1176prob.html

Thanks

Will

 

[khstudio]

[quote author="dukasound"]Excuse me if I missed
Phase on output transformer (Lundahl) of Mnats and Jacobs project are diferent.[/quote]

I THINK Mnats just flipped the PAD's & not the Phase but I'm not sure :?:

I would like to know this as well.

Kevin

 

[khstudio]

The Mnats board has the option for 1:1 or 2:1 for the Lundhal...

Which is the setup most of you are going with & why?
It says 1:1 is normal but I think the original is 2:1, no? :?

Also, any difference between using the 10k or 12k for the secondary loading :?:

Thanks,
Kevin