All things LA2a related

[wave]

Nevermind I found an LA2A BOM I had downloaded before
It answered my last questions :grin:

 

[wave]

Can you use a .1 600v cap in place of a .1 400v cap?

 

[WJS]

should hope so, as long as the quality is the same. if you are going for matching, its better to have identical parts. increasing the voltage rating for a cap means that it wont go up in smoke untill that higher voltage.a cap that will only see a few hundred volts should be rated well over that value (hence 400v) but upping to 600 shouldn't hurt.

I just finished a project which had lots of last minute buying of parts and the local radioshacks ran out of .01 uf caps rated for 500v but I found ones rated for 2kv which worked just fine.

good luck!!
and remember
going up in voltage rating is ok
be VERY carful going down

 

[wave]

Thanks WJS!!
:guinness: :guinness:

 

[WJS]

:guinness:
cant, i'm 17
but thanks, and best of luck!
(and i guess i can drink digitaly...)

 

[QNote]

Anyone used, or tried, an ECC99 tube for the output driver 12BH7A? I see Tesla has a new one out and it is supposed to replace the 12BH7A in most applications. If not, what brand 12BH7A's are ya'll using. Just curious...

 

[wave]

Talked with the guy at triode electronics. He said he was no expert but it shouldnt matter for the LA2. I'm gonna get one of his electro harmonix 12BH7 as well as the jj/tesla ECC99 just in case. Since I live in Chicago I'm gonna take the LA over to his shop so we can check it throughly.

 

[QNote]

I just ordered both from Triode, myself. I'll post any substantial findings.

 

[AnalogPackrat]

[quote author="QNote"]Anyone used, or tried, an ECC99 tube for the output driver 12BH7A? I see Tesla has a new one out and it is supposed to replace the 12BH7A in most applications. If not, what brand 12BH7A's are ya'll using. Just curious...[/quote]

I used a NOS GE 12BH7 in mine. I grabbed a box full of tubes when the lab techs were clearing out some old "junk" from the equipment repair room in the EE department. I think the 6AQ5 I used came from the same source. I love it when something I scavenged 15+ years ago is suddenly just what I need :green:

Analog Packrat

 

[AnalogPackrat]

I finally got my sh*t together and have some photos of my Bloo LA2A build. I used Sowters and added the stereo link option just in case. I'm still thinking about adding meter illumination, but haven't made up my mind yet.

Rather than use up my free BW limit everytime someone views this thread, lets try this instead (there are about 2M of images):

http://photobucket.com/albums/a173/AnalogPackrat/Bloo LA2A/

Password is "Bloo"

Let me know if this doesn't work for some reason.

Analog Packrat

 

[AnalogPackrat]

(&^*!!! Screwed up the link format...

Analog Packrat's Bloo LA2A Build

 

[wave]

Looks Good AP

 

[zhoel]

I have all the parts for my first project (LA2A which may take me years to finish) except for the output trans. I found a Triad-Utrad A-65J and was wondering if someone could tell me if it would work and how to wire it in relation to the A-24. I am a very newbie so be patient as I am trying to learn as fast as I can. Here is a link to a pic of one that was sold on Ebay.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=4665&item=7520692299&rd=1&ssPageName=WDVW

It seems there still is not enough info on the sheild to show if it will work. I am looking for more info.
Thanks
Zhoel

 

[QNote]

Zhoel,

Try this diagram for assistance (note the pri/sec reversal in this case)...

http://www.w5kp.com/n9foy-techinfo/n9foy-2.jpg

 

[wave]

Gurus,
I just finished wiring up and went for the first test. I got no neon and about .3VAC on turrets a24-25 any thoughts? Also My mains fuse blew.
Thanks

 

[AnalogPackrat]

Wave,

Does your power transformer hum (it shouldn't)? Are you getting 120VAC at the IEC connector? Be careful in there. Remember--one hand in your pocket at all times with the HV stuff. Best to clip onto ground somewhere before powering up and then probe with one hand. With no tubes in it takes a while to drain those big caps, too, so watch out near them after the power has been on.

Analog Packrat

 

[CJ]

grab the hummer with one hand, and put the other in your pocket.

 

[wave]

If I probe the hot on the IEC (bottom left from solder side) shouldn't I get my wall AC reading?

 

[wave]

Transformer not humming

 

[AnalogPackrat]

Yep. Did you mount your power switch upside down? If not, check your fuse--probably blown.