Techtalk

Hi,
just opened my 2LA2 again. Each time I turned the gain pot of the left channel to max I had a strange "uiiiiiiiiiihg" noise. I swapped tubes, changed tubes, checked the wiring, nothing changed.

Then I changed the position of the output tx (Edcors) because I found it quite close to the output XLR, although the solder lugs were isolatted with heat shrinks. Guess what, the oscillation sound has gone. RMAA specs were much better after that change. So be aware, where you put the output tx.
regards
Bernd

Hi Guys,

hope all is well,

I have a slight issue with one channel, the release time in the last 1-2dB's is super slow, almost 60 seconds to return to zero in the last dB..

i have not had time to look at any great detail, just thought id ask first for ideas as i thought that the release time was only set by the T4...i have changed the T4 but no change...

hope you guys can help,

all the best

Pete

it was the T4 in the end, I have asked Drip for a replacement.

Best
Pete

Hi Pete,

Make sure your optical cells are in place - on my two t4's the cells were completely bent out of their regular position - i gently pushed them back in, now both are working fine..

cheers
christoph

Ahh, ill take a look inside, thanks for the tip!

best
Pete

bernbrue hat geschrieben:Hi,
here is an Excel Partlist and the pcb component placement as pdf. I mailed DRIP, the price for a T4B remake is 90 USD. Will ask him for a price reduction in case we order more than ten.

http://www.twin-x.com/groupdiy/albums/u ... nt_Art.xls

Stupid question regarding the BOM (I hope no one asked this already, I only read until page 8 ):

Are the "Part Size/Name"s order numbers from any supplier?
Most of the text there is not clear to me.

Hi,
the partlist was generated by the pcb design software (Target). Most parts are available from Conrad, Reichelt and Tubetown.
regards
Bernd

I'm just about done stuffing my D-LA2A board. It looks like I've got a solder bridge between D3 and D4, and another between D5 and D6 at the points closest to the socket. Before I spend any effort trying to correct this, I just want to verify, are there traces between those points already? Thanks.

hi kafka, welcome to what I call "Franks place"
and yes, the bridge rectifier diodes have traces between D3/D4 and D5/D6 on one side and between D3/D5 & D4/D6 on the other

That's what I thought. Aside from that it just plain made sense, the solder flowed a little too easily for them not to be connected.

Hi everybody,
i'm new on DLA2 i just would to know witch resistors are on tbd ( chrismas board ) and where i can buy tb4-clone cause i can't build it.

I 've try on prodigy but all links are broken.

thanx

moin,

the TBD resistors are the ones you get with (original) T4Bs.
normaly 33K IIRC.

T4Bs can be bought from
http://www.studioelectronics.biz (NOS)
or from dripelectronics at prodigy (clones)

thanx for the quick response [silent:arts] and for the good work for us.

bernbrue hat geschrieben:So be aware, where you put the output tx.
regards
Bernd

Hi Bernd , have you got a pic to post to show the placement of your output tx???(Maybe the pics in the first post are the ones??)
Thx by advance.

Edit : oooops , forgot to mention I was new (first post).I'm very excited to start my christmas pcbs.Thx to all of you guys.

Hi,
welcome to Franks place. Just don´t put the output transformers to close to the input/output XLRs, thats all. Volker provided this "grid stopper" thing with the new revision of his board (christmas boards as well) , so oscillation won´t be an issue.
regards
Bernd

joyeux Noel et bonne année