[silent:arts]

« Last Edit: July 04, 2017, 01:20:36 AM by [silent:arts] »
SSLtech: No bypass, I don't believe in it.
Gus: I think this build might have problems with DIY builders that don't know things like ohms law.


MartyMart

Re: D-LA2A Support Thread
« Reply #1 on: March 23, 2009, 07:31:13 AM »
Great, thanks Volker ... it"s on my list !!

Marty.
"Success is the ability to go from one failure to another with no loss of enthusiasm"

Kingston

Re: D-LA2A Support Thread
« Reply #2 on: March 23, 2009, 07:35:57 AM »
a useful looking link from that thread about grid stoppers:

http://www.groupdiy.com/index.php?topic=258781

but it's for the old prodigy pro forum version..

how do I make that link compatible with the one today?

Audioman

Re: D-LA2A Support Thread
« Reply #3 on: March 23, 2009, 06:38:43 PM »
Hi All ,
Anybody have a BOM for the Dual LA-2A for the european customers including where to buy tubes and T4B cells ??
And also the right type of tubes
Thank you all !!
Fabio

tskguy

Re: D-LA2A Support Thread
« Reply #4 on: March 23, 2009, 06:46:16 PM »
I would be interested in a USA bom as well.

Eric

kazper

Re: D-LA2A Support Thread
« Reply #5 on: March 23, 2009, 06:55:03 PM »
What happened to the build thread from S.A. first build?

I just looked for it a couple weeks ago referencing the PCB I have from that buy.
Intentionally left blank

[silent:arts]

Re: D-LA2A Support Thread
« Reply #6 on: March 24, 2009, 04:00:24 AM »
What happened to the build thread from S.A. first build?
I just looked for it a couple weeks ago referencing the PCB I have from that buy.
there never was a build thread except the one at Franks place.

Anybody have a BOM for the Dual LA-2A for the european customers including where to buy tubes and T4B cells ??
And also the right type of tubes
here you find some links for the caps I used, and a BOM bernbrue once did.
T4Bs:
http://www.dripelectronics.com/t4b.html
http://www.studioelectronics.biz/sunshop/index.php?l=product_detail&p=1142
SSLtech: No bypass, I don't believe in it.
Gus: I think this build might have problems with DIY builders that don't know things like ohms law.

tskguy

Re: D-LA2A Support Thread
« Reply #7 on: March 24, 2009, 02:18:26 PM »
Would any la2a bom work for most of this build? I have found some US friendly BOM's for diffrent layouts and was wondering if most of it would be the same?

Eric

RAM

Re: D-LA2A Support Thread
« Reply #8 on: March 24, 2009, 03:38:38 PM »
It'll probably work for the resistors at least. But most of the electrolytic caps may not fit on the board. Plus the PSU is different.

Rob

tskguy

Re: D-LA2A Support Thread
« Reply #9 on: March 24, 2009, 05:58:13 PM »
Thanks,

I actually orderd the PSU from the group buy so Im good to go there. As for caps I can figure that out pretty easily.

Im just being lazy Im sure I can get together a BOM onmy own pretty quickly.

Eric


tskguy

Re: D-LA2A Support Thread
« Reply #10 on: March 24, 2009, 09:07:59 PM »

Silvas

Re: D-LA2A Support Thread
« Reply #11 on: March 24, 2009, 09:28:08 PM »
This thread is great news !!!

Now, to the questions :

Will the antek 1T250 work here?

Seems like an economical option...i think the voltages and VA´s are right

[silent:arts]

Re: D-LA2A Support Thread
« Reply #12 on: March 25, 2009, 06:08:31 AM »
Will the antek 1T250 work here?
looks good to me, but you won't have any relay power for the bypass (actually those are "compressor in" relays.

Eric, your relays are fine.
SSLtech: No bypass, I don't believe in it.
Gus: I think this build might have problems with DIY builders that don't know things like ohms law.

deuce42

Re: D-LA2A Support Thread
« Reply #13 on: March 25, 2009, 06:43:32 AM »
Great thread idea Silent Arts.

To everyone else, Silent Arts has been so helpful in my experience at the "Franks Place" forum for this project and I am glad the thread can continue here at groupdiy.

Now for my question, since these things put out huge amounts of gain, can I substitute input transformers and use 1:1 ratio transformers rather than the normal 1:4 to lower the amount of gain? Besides substituting the 100k gain pot for a the 25kpot/75k resistor as discussed at Franks Place , could I substitute 1:1 input transformers instead?  I have these Sowters lying around which are 600/600 ohms 1:1  and I would love to make use of them.

Thanks

[silent:arts]

Re: D-LA2A Support Thread
« Reply #14 on: March 25, 2009, 07:01:27 AM »
Now for my question, since these things put out huge amounts of gain, can I substitute input transformers and use 1:1 ratio transformers rather than the normal 1:4 to lower the amount of gain?
yes you can ;)
SSLtech: No bypass, I don't believe in it.
Gus: I think this build might have problems with DIY builders that don't know things like ohms law.

tskguy

Re: D-LA2A Support Thread
« Reply #15 on: March 25, 2009, 08:30:17 AM »
Thanks,

I was wondering about the input iron also. Im considering using Lundhal transformers and Talked with Kevin the US distribitor and he suggested using 1:1 on the input as well.
Im working on a USA Bom and noticed I cant find the silver Mica caps. Does anybody have a usa source for those?

Eric

[silent:arts]

Re: D-LA2A Support Thread
« Reply #16 on: March 25, 2009, 09:40:37 AM »
Eric, I doesn't have to be Silver Micas
SSLtech: No bypass, I don't believe in it.
Gus: I think this build might have problems with DIY builders that don't know things like ohms law.

tskguy

Re: D-LA2A Support Thread
« Reply #17 on: March 25, 2009, 09:54:41 AM »
Thats what I figured but I thought that I would try and stay true to your original design.

Eric

deuce42

Re: D-LA2A Support Thread
« Reply #18 on: March 25, 2009, 10:14:33 AM »
Awesome - thanks! These are special 4757 Sowters made for the BBC. Will givem them a go and then report back:)

Silvas

Re: D-LA2A Support Thread
« Reply #19 on: March 25, 2009, 11:20:26 AM »
Will the antek 1T250 work here?
looks good to me, but you won't have any relay power for the bypass (actually those are "compressor in" relays.

Eric, your relays are fine.

But it is possible to steal some voltage from the heaters secondary to do this right? running the relays at 5v ? or i can use a second toroid (have lots of 10va anteks lying around).

Thanks !